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1.	Ranucci, E., et al. (författare) New ester and lactone end-functionalized N-vinyl-2-pyrrolidinone oligomers 2000 Ingår i: Macromolecular Chemistry and Physics. - 1022-1352 .- 1521-3935. ; 201:12, s. 1219-1225 Tidskriftsartikel (refereegranskat)abstract New oligomers of N-vinyl-2-pyrrolidinone functionalized at one end with either ester or lactone functions were obtained by radical polymerization in the presence of different ester (methyl isobutyrate and methyl phenylacetate) and lactone (epsilon-caprolactone, delta-valerolactone and gamma-btyrolactone) compounds as chain transfer agents. The oligomeric samples obtained were characterized in terms of molecular weight and molecular weight distribution by means of analytical size exclusion chromatography (SEC), using purposely synthesized poly(N-vinyl-2-pyrrolidinone) standards. The chain transfer constant C-tau of either methyl isobutyrate, delta-valerolactone, or gamma-butyrolactone towards N-vinyl-2-pyrrolidinone were determined with the help of the known cumulative number-average degree of polymerization (X) over bar(n) and monomer conversion Y-t of the samples during the reaction.
2.	Hakkarainen, Minna, et al. (författare) Heterogeneous biodegradation of polycaprolactone - Low molecular weight products and surface changes 2002 Ingår i: Macromolecular Chemistry and Physics. - 1022-1352 .- 1521-3935. ; 203:11-okt, s. 1357-1363 Tidskriftsartikel (refereegranskat)abstract Gas chromatography-mass spectrometry (GC-MS) analysis showed that caprolactone, 6-hydroxyhexanoic acid, cyclic dimer and cyclic trimer were rapidly assimilated from the surface of polycaprolactone (PCL) films aged in mineral medium inoculated with a mixed culture of compost microorganisms. The degradation in biotic medium proceeded heterogeneously and scanning electron micrographs revealed the formation of parallel grooves, spherical and non-spherical holes in the films. The parallel grooves seen in the scanning electron micrographs after 14 d suggest that the degradation starts preferentially at the amorphous regions. At longer time scales, even the crystalline regions are degraded producing large spherical and non-spherical holes. Comparison of the degradation of melt-pressed and film-blown films made from the same PCL granules in different biotic and abiotic environments showed that both the type of microorganism used and the initial morphology of the films influence the surface erosion pattern and biodegradation mechanism. Rapid degradation and molecular weight decrease required the combined effect of temperature and microorganisms obtained during a biodegradation process, such as composting.
3.	Achtel, Christian, et al. (författare) Dissolution capacity of novel cellulose solvents based on triethyloctylammonium chloride 2017 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 218:21 Tidskriftsartikel (refereegranskat)abstract Dissolution of cellulose from various sources (microcrystalline cellulose and different dissolving grade pulp fibers) is investigated in solvent systems based on triethyl(n-octyl)ammonium chloride (N2228Cl). Clear cellulose solutions are obtained with N2228Cl in a variety of solvents, e.g., dimethyl sulfoxide, N,N-dimethylacetamide, and acetone. It is possible to prepare clear cellulose solutions from pulp fibers with concentrations up to 15 wt%. However, it is found that the cellulose is degraded, especially when neat (i.e., molten) N2228Cl is used as a solvent. The present work includes comprehensive rheological characterization of the cellulose solutions, both with shear and extensional rheology. In most cases, the viscosity values are low (complex viscosities below 100 Pa s for 5–10 wt% dissolved cellulose), and the solutions show more Newtonian than viscoelastic behavior.
4.	Alexakis, Alexandros Efraim, et al. (författare) Modification of CNF‐Networks by the Addition of Small Amounts of Well‐Defined Rigid Cationic Nanolatexes 2022 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 224:1, s. 2200249-2200249 Tidskriftsartikel (refereegranskat)abstract Cellulose nanofibril (CNF)-networks are modified by the addition of small amounts (below 10 wt%) of well-defined cationic nanolatexes synthesized through reversible addition–fragmentation chain-transfer-mediated polymerization-induced self-assembly (PISA). Minute amounts of nanolatex inclusions lead to increased tensile and shear moduli, indicating that nanolatexes can act as bridging-points between CNFs. At higher nanolatex content, this stiffening effect is lost, likely due to interactions between nanolatexes leading to plasticization. The influence of nanolatex content and size on interparticle distance is discussed and is used as a tool to understand the effects observed in macroscopic properties. Upon annealing, the stiffening effect is lost due to the softening of the nanolatexes, indicating that the core–shell morphology is a prerequisite for this effect. These systems form a versatile platform to develop fundamental insights into complex condensed colloidal systems, to ultimately aid in the development of new sustainable material concepts.
5.	Andac, M, et al. (författare) Poly(hydroxyethyl methacrylate)-based macroporous hydrogels with disulfide cross-linker 2008 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1521-3935 .- 1022-1352. ; 209:6, s. 577-584 Tidskriftsartikel (refereegranskat)abstract Biodegradable supermacroporous PHEMA cryogels were produced by combining two cross-linkers, poly(ethylene glycol) diacrylate and a newly developed disulfide water soluble crosslinker, N,N'-bis(methacryloyl)-L-cystine. The biodegradable PHEMA cryogels were prepared with gel fraction yields up to 70% and were characterized by highly interconnected pores of micrometer size and good mechanical stability. When subjected to reductive agents like DTT, the biodegradable PHEMA cryogels disintegrated into small pieces. The rate of disintegration was controlled by the crosslinking density in the cryogels and the DTT concentration.
6.	Andersson, Mattias, 1985, et al. (författare) Influence of Molecular Weight on the Creep Resistance of Almost Molten Polyethylene Blends 2018 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 219:3 Tidskriftsartikel (refereegranskat)abstract The most common route to improve the creep resistance of low density polyethylene (LDPE) is crosslinking, which however results in volatile decomposition products that must be removed. Blends of LDPE and an additive-like amount of a linear polyethylene are found to offer improved creep resistance. Above the melting temperature of LDPE, T m ≈ 111 °C, a load-bearing network of higher-melting crystallites—connected through tie chains and trapped entanglements—provides additional form stability. The molecular weight of the linear polyethylene is found to be critical for the ability to arrest creep, which is correlated with the probability of tie chain formation as well as cocrystallization of the two polyethylenes. A number of high-density polyethylenes (HDPE) and one ultrahigh molecular weight polyethylene (UHMW-PE) are explored. For blends of LDPE and 2 wt% of the linear polyethylene, an HDPE with a weight-average molecular weight M w of 16 kg mol −1 is found to be sufficient to arrest creep at 115 °C. Further improvement in terms of creep resistance is obtained in case of UHMW-PE with creep fracture occurring only at a stress of 12 kPa at 115 °C. (Figure presented.).
7.	Andersson, Per (författare) Pressure dependence of the thermal conductivity of some polyamides 1976 Ingår i: Macromolecular Chemistry and Physics. - Basel : Wiley. - 1022-1352 .- 1521-3935. ; 177, s. 271-277 Tidskriftsartikel (refereegranskat)abstract The pressure dependence of the thermal conductivities of five polyamides (nylons) have been determined ina cylindrical geometry at 300 K and in the pressure range 0-25 kbar. The conductivities increase strongly with pressure, the values at 25 kbar being higher by the factors 1,83, 1,90, 2,07, and 2,03 for, respectively, nylon 66, nylon 610, nylon 6, nylon 11, and nylon 12, than those at atmospheric pressure. The results are compared with other exerimental results and with theoretical calculations. The difference in conductivity response to pressure between the different varieties is discussed.
8.	Bini, Kim, 1987, et al. (författare) Synthesis and Characterization of Isoindigo-Based Polymers with Thermocleavable Side Chains 2018 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 219:7 Tidskriftsartikel (refereegranskat)abstract Stability of bulk heterojunction films for organic solar cells is a critical factor for commercial viability. One method to stabilize these films is to include cleavable side chains, which reduce the solubility of the polymers when removed. In order to study the stabilizing effect of cleavable side chains, a series of random copolymers using isoindigo with 0, 10, 20, 50, and 100% thermally cleavable side chains based on the tert-butyloxycarbonyl (t-BOC) group are synthesized. The polymers show a distinct one-step thermal cleavage of the side chains, with no separable dealkylation and decarboxylation steps. The thermal stability in film is studied with transmission electron microscopy and atomic force microscopy. The polymer with all t-BOC side chains on isoindigo significantly improves thermal stability with regard to crystal growth and phase separation in film. These results suggest BOC-substitution can be used for large scale processing to produce insoluble polymer films with a high degree of thermal stability.
9.	Brännström, Sara, et al. (författare) Tailoring Thermo-Mechanical Properties of Cationically UV-Cured Systems by a Rational Design of Vinyl Ether Ester Oligomers using Enzyme Catalysis 2018 Ingår i: Macromolecular Chemistry and Physics. - : WILEY-V C H VERLAG GMBH. - 1022-1352 .- 1521-3935. ; 219:21 Tidskriftsartikel (refereegranskat)abstract There is a demand for new sustainable polymeric materials. Vinyl ethers are, in this context, attractive oligomers since they polymerize fast, are non-toxic, and can be polymerized under ambient conditions. The availability of vinyl ether oligomers is, however, currently limited due to difficulties in synthesizing them without using tedious synthesis routes. This work presents the synthesis of a series of vinyl ether ester oligomers using enzyme catalysis under solvent-free conditions and the subsequent photoinduced cationic polymerization to form polymer thermosets with T(g)s ranging from -10 to 100 degrees C. The whole process is very efficient as the synthesis takes less than 1 h with no need for purification and the crosslinking is complete within 2 min.
10.	Carlmark, Anna (författare) Tailoring cellulose surfaces by controlled polymerization methods 2013 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 214:14, s. 1539-1544 Tidskriftsartikel (refereegranskat)abstract Cellulose, with its excellent mechanical properties and low weight, would be highly advantageous to employ in bioplastics and biocomposites applications. However, to expand the utilization of cellulose beyond its traditional uses, a modification of the fiber surface is often a prerequisite. One approach is to graft polymer chains on the surface in order to compatibilize the fibers with a non-polar polymer matrix or to introduce functionalities. By exploiting controlled polymerization methods such as ATRP, RAFT, ROP, and ROMP, the surface of the fibers can be carefully tailored. Herein, an overview on controlled, heterogeneous grafting of cellulose fibers and fibrils employing both "grafting from" and "grafting to" methodologies is provided, focusing on the latest findings.
11.	Derazshamshir, Ali, et al. (författare) Molecularly Imprinted PHEMA-Based Cryogel for Depletion of Hemoglobin from Human Blood 2010 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1521-3935 .- 1022-1352. ; 211:6, s. 657-668 Tidskriftsartikel (refereegranskat)abstract A new generation of molecularly imprinted macroporous hydrogels, so-called cryogels, were prepared for depletion of hemoglobin from human blood. Hb-PHEMAH cryogels were prepared with gel fraction yields up to 90%, and its morphology and porosity were characterized by FTIR, SEM, swelling studies, flow dynamics and surface area measurements. Selective binding experiments were performed in the presence of competitive PHEMAH cryogel exhibited a high binding capacity and selectivity for Hb in the presence of Myb and BSA. The selectivity of Hb-PHEMAH cryogel for Hb was confirmed by HPLC. Hb depletion from blood hemolysate was also studied using SDS-PAGE. Hb-PHE-MAH cryogel can be reused many times with no apparent decrease in Hb adsorption capacity.
12.	Engström, Joakim, et al. (författare) In situ encapsulation of Nile red or Doxorubicin during RAFT-mediated emulsion polymerization via polymerization-induced self-assembly for biomedical applications 2020 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. Tidskriftsartikel (refereegranskat)
13.	Feng, Zhaoxuan, et al. (författare) Photocrosslinked Chitosan Hydrogels Reinforced with Chitosan-Derived no-Graphene Oxide 2019 Ingår i: Macromolecular Chemistry and Physics. - : Wiley-VCH Verlagsgesellschaft. - 1022-1352 .- 1521-3935. ; 220:13 Tidskriftsartikel (refereegranskat)abstract Chitosan and chitosan-derived nano-graphene oxide carbon dots are successfully methacrylated and utilized for the fabrication of photocurable hydrogels. The addition of the nano-graphene oxide (nGO) does not significantly delay the polymer network build-up, but significantly reduces the storage modulus of the crosslinked network, with important detrimental effects on the mechanical performance. By replacing nGO with methacrylated M-nGO, the mechanical performance of the crosslinked polymer network is improved with an increase of the storage modulus as a function of increasing the M-nGO content in the photocurable formulation.
14.	Finnveden, Maja, et al. (författare) One-Component Thiol-Alkene Functional Oligoester Resins Utilizing Lipase Catalysis 2016 Ingår i: Macromolecular Chemistry and Physics. - : John Wiley & Sons. - 1022-1352 .- 1521-3935. Tidskriftsartikel (refereegranskat)abstract Chemo-enzymatic methods are powerful tools for the synthesis of novel materials. By combining the flexibility of chemical synthesis and the high selectivity of enzymes, a variety of functional materials can be achieved. In the present study, a series of α,ω-thiol telechelic oligoesters with varying amount of internal alkenes are prepared using selective lipase catalysis and are subsequently cross-linked by thiol-ene chemistry yielding alkene functional networks. Due to the reactivity of thiols and alkenes almost all present thiol-ene systems consist of two components. This work demonstrates that selective lipase catalysis in combination with renewable monomers with internal alkenes is a promising system for achieving one-component thiol-alkene functional resins with good storage stability and a high degree of thiol end-groups. The developed chemo-enzymatic route yields polymer networks with tailored amount of alkene functionalities in the final thermoset, which facilitate further postmodification.
15.	Fuoco, Tiziana, PhD, 1986-, et al. (författare) Multipurpose Degradable Physical Adhesive Based on Poly(d,l-lactide-co-trimethylene Carbonate) 2020 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 221:10 Tidskriftsartikel (refereegranskat)abstract Solutions of amorphous poly(d,l-lactide-co-trimethylene carbonate)s (PDLTMCs) in ethyl acetate work as solvent-based physical adhesives through diffusion mechanisms for a variety of aliphatic polyester-based adherents. The random PDLTMCs with a trimethylene carbonate content of 11, 16, and 20 mol% are synthesized in bulk, achieving high molecular weight, M-n, up to 128 kg mol(-1) and dispersity around 1.7. The PDLTMCs are amorphous and have a glass transition temperature in the range 34.7 to 43.6 degrees C and in agreement with the theoretical values calculated using the Fox equation. The mechanical and surface properties of the PDLTMCs are tested preparing solvent cast films, which are soft and tough and, although they have a higher contact angle than the parent homopolymer, they show higher water uptake capacity. The potential application as adhesives of the synthesized PDLTMCs is evaluated by preparing a 20 wt% solution in ethyl acetate and testing them by adhering films with different compositions as well as constructs having different geometries and surface roughness. The results demonstrate that the adhesion strength is higher on adherent films having similar chemical compositions as the adhesives and on surfaces having similar compositions to each other but different roughness. The similar chemical nature of the adhesive and adherent probably favors the diffusion mechanism through which adhesion takes place.
16.	Golabi, Mohsen, et al. (författare) Tuning the surface properties of polypyrrole films for modulating bacterial adhesion. 2016 Ingår i: Macromolecular Chemistry and Physics. - : John Wiley & Sons. - 1022-1352 .- 1521-3935. ; 217:10, s. 1128-1135 Tidskriftsartikel (refereegranskat)abstract Tuning the physical–chemical properties of polypyrrole (PPy) opens up potentially exciting new applications, especially in the area of bacterial adhesion. Polypyrrole is electrochemically synthesized under various conditions and the physical properties of the films and their effects on bacterial adhesion are characterized. Five types of dopants—chloride (Cl), perchlorate (ClO4), p-toluene-sulfonate (ToS), dodecylbenzene sulfonate (DBS), and poly sodium styrene sulfonate (PSS)—are used to fabricate PPy films at two different constant potentials (0.500 and 0.850 V) with and without Fe3+. Their thickness, roughness, and wettability are measured. The adhesion tendency of Escherichia coli, as a model bacterium, to the four polymers is studied. E. coli shows greater adhesion tendency to the hydrophobic, rough surface of PPy-DBS, and less adhesion tendency to the smooth and hydrophilic surface of PPy-PSS. The results facilitate the choice of appropriate electropolymerization conditions to modulate bacterial adhesion.
17.	Guo, Pengzhi, et al. (författare) Twisted Alkylthiothien-2-yl Flanks and Extended Conjugation Length Synergistically Enhanced Photovoltaic Performance by Boosting Dielectric Constant and Carriers Kinetic Characteristics 2021 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 222:12 Tidskriftsartikel (refereegranskat)abstract Alternating conjugated polymers (CPs), derived from 2-ethylhexylthiothiophen-2-yl (TS) or 2-ethylhexylthiophen-2-yl (T) flanked dithieno[3,2-d:3,2-d ']benzo[1,2-b:4,5-b ']dithiophene (DTBDT) and diketopyrrolo-pyrrole (DPP) termed as PDTBDT-TS-DPP and PDTBDT-T-DPP, are prepared and characterized. It is found that the PDTBDT-TS-DPP not only exhibits slightly deepening the highest occupied molecular orbital energy levels, and similar absorption, etc., but also presents higher dielectric constant (epsilon(r)) of 6.7 at 1 kHz in contrast to 3.2 for PDTBDT-T-DPP, which are even higher than those of 4.3 and 3.0 for PBDT-TS-DPP/PBDT-T-DPP generated from TS and T flanked benzo[1,2-b:4,5-bMODIFIER LETTER PRIME]dithiophene and DPP. Beyond that, the power conversion efficiency of 8.17% for the inverted photovoltaic devices from DPP-based CPs, is achieved from PDTBDT-TS-DPP. The alkylthio side chains are used in the DTBDT of the larger twisting angles of TS flanks and longer conjugation length, synergistically contribute to the highest dipole moments, and then lead to the enhancement of epsilon(r), thus devoted the modification exciton dissociation and charge carriers kinetic characteristics. To the authors' knowledge, it is the first time to report that epsilon(r) of the CPs is connected with the twisting angle of flanks and conjugation length of the building blocks, besides the use of functional side chains and atoms.
18.	Jannasch, Patric, et al. (författare) Configuring anion-exchange membranes for high conductivity and alkaline stability by using cationic polymers with side chains 2016 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1521-3935 .- 1022-1352. ; 217:10, s. 1108-1118 Forskningsöversikt (refereegranskat)abstract Polymeric anion-exchange membranes (AEMs) are critical components for alkaline membrane fuel cells (AMFCs) which offer several attractive advantages including the use of platinum-free catalysts and a wide choice of fuel. The development of AMFCs and other electrochemical energy systems is currently severely limited by the lack of AEMs with sufficient alkaline stability. Still, significant advances have been made in recent years and one of the most promising approaches to emerge is the design and synthesis of cationic polymers with various side chain arrangements. Especially, synthetic strategies where the cationic ion exchange groups are placed on pendant alkyl spacer chains along the backbone seem to significantly improve microphase separation, hydroxide ion conductivity, and alkaline stability in relation to standard AEMs with cations placed in benzylic positions directly on the backbone. This article reviews recent approaches to high-performance cationic membrane polymers involving different side chain designs, and discusses some possible future directions.
19.	Kee, Seyoung, et al. (författare) Tuning the Mechanical and Electrical Properties of Stretchable PEDOT:PSS/Ionic Liquid Conductors 2020 Ingår i: Macromolecular Chemistry and Physics. - : John Wiley & Sons. - 1022-1352 .- 1521-3935. ; 221:23 Tidskriftsartikel (refereegranskat)abstract Conducting polymers (CPs) constitute a promising building block to establish next-generation stretchable electronics. However, achieving CPs with both high electrical conductivity and outstanding mechanical stretchability beyond flexibility is still a major challenge. Therefore, understanding the key factors controlling such characteristics of CPs is required. Herein, a method to simultaneously manipulate the mechanical and electrical properties of a representative CP, PEDOT:PSS, by modifying ionic liquid (IL) additives is reported. The cation/anion modification of ILs distinctly improves the electrical conductivity of PEDOT:PSS up to ≈1075 S cm−1, and the PEDOT:PSS/IL films showing higher conductivity also exhibit superior electromechanical stretchability, enabling them to maintain their initial conductivity under a tensile strain of 80%. Based on grazing incidence wide angle X-ray scattering and Fourier transform infrared spectroscopy analyses, it is found that the cation/anion-modified ILs control the crystallinity and π–π stacking density of conjugated PEDOT chains and the growth of amorphous PSS domains via IL-induced phase separation between PEDOT and PSS, which can be the origin of the significant conductivity and stretchability improvements in PEDOT:PSS/IL composites. This study provides guidance to develop highly stretchable CP-based conductors/electrodes.
20.	Lindqvist, Camilla, 1985, et al. (författare) Facile Monitoring of Fullerene Crystallization in Polymer Solar Cell Blends by UV–vis Spectroscopy 2014 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 215:6, s. 530-535 Tidskriftsartikel (refereegranskat)abstract A simple technique is demonstrated based on UV–vis spectroscopy that permits the onset of fullerene crystallization to be monitored in polymer:fullerene bulk-heterojunction blends. The growth of fullerene crystals only occurs during thermal annealing above the glass transition temperature (Tg) of the blend. Light scattering due to the presence of micrometer-sized fullerene crystals reduces the apparent transmittance, which can serve as a clear indicator for the upper limit of the Tg. This principle is used to deduce this critical parameter for two high-performance photovoltaic blends that are based on a thiophene–quinoxaline and a thiophene–isoindigo copolymer, respectively. High Tgs of 115 and 145 °C promise good thermal stability.
21.	Loaiza Rodriguez, Laura, 1990, et al. (författare) Li-Salt Doped Single-Ion Conducting Polymer Electrolytes for Lithium Battery Application 2022 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. Tidskriftsartikel (refereegranskat)abstract Traditionally solid polymer electrolytes (SPEs) for lithium battery application are made by dissolving a Li-salt in a polymer matrix, which renders both the Li+ cations, the charge carriers of interest, and the anions, only by-standers, mobile. In contrast, single-ion conductors (SICs), with solely the Li+ cation mobile, can be created by grafting the anions onto the polymer backbone. SICs provide the safety, mechanical stability, and flexibility of SPEs, but often suffer in ionic conductivity. Herein an intrinsically synergetic design is suggested and explored; one dopes a promising SIC, LiPSTFSI (poly[(4-styrenesulfonyl) (trifluoromethanesulfonyl)imide]), with a common battery Li-salt, LiTFSI. This way one both increases the Li+ concentration and transport. Indeed, systematically exploring doping, it is found that 50-70 wt% of LiTFSI renders materials with considerable improvements in both the (Li+) dynamics and the ionic conductivity. A deeper analysis allows to address connections between the ion transport mechanism(s) (Arrhenius/VTF), the charge carrier speciation and concentration, and the free volume and glass transition temperature. While no silver bullet is even remotely found, the general findings open paths to be further explored for SPEs in general and Li-salt doped SICs in particular.
22.	Lobov, Gleb S., et al. (författare) Size Impact of Ordered P3HT Nanofibers on Optical Anisotropy 2016 Ingår i: Macromolecular Chemistry and Physics. - : John Wiley & Sons. - 1022-1352 .- 1521-3935. ; 217:9, s. 1089-1095 Tidskriftsartikel (refereegranskat)abstract Poly-3-hexylthiophene (P3HT) nanofibers are 1D crystalline structures with semiconductor properties. When P3HT nanofi bers are dispersed in nonconducting solvent, they react to external alternate electric field by aligning along the field lines. This can be used to create layers of ordered nanofi bers and is referred to as alternating current poling method. P3HT nanofi bers with three different size distributions are fabricated, using self-assembly mechanism in marginal solvents, and used for the alignment studies. Anisotropic absorption of oriented 2 mu m long nanofi bers exponentially increases with the magnitude of applied field to a certain asymptotic limit at 0.8 V mu m(-1), while 100-500 nm long nanofi bers respond to electric field negligibly. Effective optical birefringence of oriented 2 mu m long nanofi bers is calculated, based on the phase shift at 633 nm and the average layer thickness, to be 0.41. These results combined with further studies on real-time control over orientation of P3HT nanofi bers in liquid solution or host system are promising in terms of exploiting them in electroabsorptive and electrorefractive applications.
23.	Lynch, Iseult, et al. (författare) Effect of a polymeric additive on the pore-size distribution and shrinking process of a hydrogel network 2003 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1521-3935 .- 1022-1352. ; 204:3, s. 443-450 Tidskriftsartikel (refereegranskat)abstract A systematic comparison of the effect of architectural modifications to the network structure on the internal microstructure of N-isopropylacrylamide (NIPA) based hydrogels showed that the addition of a second component to the network significantly increased the proportion of macropores in the network. The second components considered were short poly(N-isopropylacrylamide)(PNIPAM) chains grafted to the network backbone, high-molecular-weight polyacrylamide (PAM) chains, or microsphere particles of PNIPAM. Structures are proposed for each of the modified gel networks taking into account the new structural information. Through combination of the pore size and network structure data reported here, and with the shrinking data obtained previously, shrinking mechanisms are proposed for each of the modified network structures. In all cases, the enhanced shrinking rates were directly caused by the presence of the second component, which acted as nuclei for shrinking (graft-PNIPAM and PNIPAM microspheres) or as water-release channels (PAM gel), and indirectly caused by the second components via their affect on the network microstructure.
24.	Löwenhielm, Peter, et al. (författare) Poly (neopentylene carbonate) hyperstars 2004 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 205:11, s. 1489-1496 Tidskriftsartikel (refereegranskat)abstract Branched aliphatic polycarbonates were synthesized by ring opening polymerization of 5,5-dimethyl-1,2-dioxane-2-one (NPC) initiated from polyfunctional alcohols and a commercial hyperbranched polyester (BOLTORN(R)). Polymerizations in the presence of fumaric acid under bulk conditions allowed high conversion (80%) without gelation. The synthesis of polymers with long chain branches was confirmed by size exclusion chromatography and universal calibration. The Mark-Houwink exponent decreased, indicating an increased density, while increasing the number of arms. The star polymers with up to four arms showed thermal properties T-g (20-30degreesC) and T-m (100-110degreesC) similar to linear PNPC.
25.	Malmstrom, E, et al. (författare) The effect of terminal alkyl chains on hyperbranched polyesters based on 2,2-bis(hydroxymethyl)propionic acid 1996 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 197, s. 3199-3207 Tidskriftsartikel (refereegranskat)abstract A hyperbranched hydroxyfunctional polyester based on 2,2-bis(hydroxymethyl)propionic acid as AB(2)-monomer and a tetrafunctional polyol as core was end-capped with five different alkylacyl chlorides. Alkyl chain lengths ranging from three to sixteen carbons were used. Short alkyl chains (3-6 carbons) decrease the glass transition temperature from around 30 degrees C for the hydroxyterminated polyester to temperatures well below zero. With a sufficiently long alkyl chain (12-16 carbons) the polymers tend to crystallize. The polyesters with C-16-chains as terminal groups exhibit several different crystalline phases as revealed by differential scanning calorimetry. From X-ray data it was possible to suggest that the crystallization for the C-16-terminated samples occurs in a non-interpenetrating fashion for the larger sample and in an interpenetrating way for the smaller polymers.
26.	Shiomori, Koichiro, et al. (författare) Thermoresponsive properties of sugar sensitive copolymer of N-isopropylacrylamide and 3-(acrylamido)phenylboronic acid 2004 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1521-3935 .- 1022-1352. ; 205:1, s. 27-34 Tidskriftsartikel (refereegranskat)abstract The copolymer of N-isopropylacrylamide and 3-(acrylamido)phenylboronic acid (82:18, (M) over bar (n)=47000 g. mol(-1)) was prepared by free radical polymerization. The copolymer showed typical thermal precipitation behavior in aqueous solutions, its precipitation temperature (T-P) being increased from 23 to 32degreesC by increasing the pH from 6.5 to 9.7, because of ionization of the phenylboronate units. The pK(a) was evaluated as 8.9+/-0.1 from the effect of pH on T-P. At pH>9, i.e., in the anionic form of the copolymer, T-P was affected by a very low concentration of glucose (5.6 muM, DeltaT(P)=1-1.5degreesC), because of complex formation with a high binding constant. At a higher concentration of polyols (560 muM, pH>8) the increase of T-P was maximal for the copolymer complexes with fructose (7-10degreesC) and decreased in the order: fructose>glucoseapproximate tomannitol>pentaerythritol>galactose>Tris>glycerol. Di- and oligosaccharides (lactose, sucrose, and dextran) caused a slight increase of T-P at pH 7.5-8.7 while no effect was observed at pH>9. Isothermal dissolution of the copolymer suspension in water (27degreesC, pH 8.5) was possible in the. presence of fructose or mannitol but required higher concentrations (1.4-3.6 x 10(3) muM) as compared to those which enabled the shift of T-P in the soluble copolymer. The dissolution rate increased with fructose concentrations.
27.	Skodova, Michaela, et al. (författare) Novel Polymeric Nanoparticles Assembled by Metal Ion Addition 2011 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 212:21, s. 2339-2348 Tidskriftsartikel (refereegranskat)abstract Potentially biodegradable graft polymer core-shell nanoparticles assembling by addition of metal ions intended to be used for radionuclide and drug delivery purposes are described. With Cu2+ ions, the self-assembly is slow (within minutes) with low efficiency. With Fe3+ ions the nanoparticles are formed immediately and are of convenient size for passive tumor accumulation by the enhanced permeation and retention effect. Full in vitro degradation of these particles is achieved with deferoxamine as a model of in vivo transchelation capacity.
28.	Tahir, M. Nazir, et al. (författare) Alkynyl Ethers of Glucans : Substituent Distribution in Propargyl-, Pentynyl- and Hexynyldextrans and -amyloses and Support for Silver Nanoparticle Formation 2010 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 211:15, s. 1648-1662 Tidskriftsartikel (refereegranskat)abstract Alkynyldextrans with a DS in the range 0.1-1.67 have been prepared as reactive intermediates for further polymer-analogous functionalisation.. DS and substituent distribution were determined by GLC and GLCMS after hydrolysis and acetylation, or methanolysis and trimethylsilylation. Reactivity was in the order O-2 > O-4 >= O-3 with pronounced differences in the distinct patterns for propargyl ethers and its higher homologous. A large deviation from a random substituent distribution was observed. Propargyldextrans were not stable during long-time storage in the solid state, while terminal pentynyl and hexynyl ethers are. Pentynyldextrans showed structure formation of various geometries. They bound silver efficiently, yielding silver nanoparticles by reduction.
29.	Tang, Qingquan, et al. (författare) Topological Effects on Cyclic Co-Poly(ionic liquid)s Self-Assembly 2023 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 224:3 Tidskriftsartikel (refereegranskat)abstract Topological geometry of poly(ionic liquid)s (PILs), such as brush-like, knot-like, hyperbranched and randomly coiled, often exerts a strong influence on their self-assembly behaviors. As a primary topological form, the cyclic topology-derived effects have not been investigated on PILs, which concerns synergy of charges and zero chain end. Herein, linear and cyclic poly(ionic liquid) copolymers (co-PILs) with randomly distributed counter anions of B(Ph)4− and Br− by a template method in combination with a follow-up partial anion exchange is prepared. The self-assembly phenomena of linear and cyclic co-PILs are studied in selective solvents, where the hydrophobic counter anions B(Ph)4− and hydrophilic counter anions Br− aggregated to form cores and corona in the assembled nanospheres, showing the average size of cyclic co-PILs nanospheres is 46.2% smaller (≈120 nm) than linear co-PILs nano-assemblies (≈176 nm). Based on the CGMD simulations, the authors speculate that the spherical aggregates are formed by transitioning from micelles with gradient block-like structures, which formed by enriched hydrophobic counter anions in the core and enriched hydrophilic counter anions in the corona. These results indicate a novel synergy of topology effects and dynamic anion movements, as revealed by cyclic co-PIL self-assembly in this work.
30.	Torron, Susana, et al. (författare) Polymer Thermosets from Multifunctional Polyester Resins Based on Renewable Monomers 2014 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 215:22, s. 2198-2206 Tidskriftsartikel (refereegranskat)abstract The use of monomers based on natural materials as a future supply of raw materials has gained more interest in the last decade. Sources ranging from wood to plant oils and algae are exploited as alternatives to traditional fossil-based resources for the synthesis of polymeric materials. The use of these raw materials is not only of interest because of its abundance, but also in terms of price, durability, and/or biodegradability. In the present study, a series of resins utilizing a monomer derived from birch bark is prepared. The thermoset resins are formed by reacting an epoxy-functional omega-hydroxy fatty acid with methacrylate monomers using enzyme catalysis to form multifunctional resins via a one-pot synthesis. The derived oligomers are crosslinked through different polymerization routes to produce thermosets with different properties and/or functionalities. This approach allows natural-based resins with tuned functionalities and mechanical and thermal properties to be obtained.
31.	Ture, Hasan, et al. (författare) Nanostructured Silica Wheat Gluten Hybrid Materials Prepared by Catalytic Sol-Gel Chemistry 2013 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 214:10, s. 1131-1139 Tidskriftsartikel (refereegranskat)abstract The main physicochemical properties of nanostructured silica/wheat gluten hybrid composites are presented. The extraction experiments suggest that the protein phase is intimately encased within the silica matrix, with silica–protein interactions driven by hydrogen bonding, as indicated by IR spectra. Spectroscopic results also show that silica induces a higher degree of constraint of the wheat gluten matrix, despite less aggregation. Moisture diffusion properties of the hybrid materials are investigated by a combined “desorption/sorption” approach. While the reduction of the moisture diffusivity in the presence of silica can be described by the geometrical impedance of a “sintered” porous solid, a time-dependent relaxation/restructuring of the composite apparently occurs during the sorption-desorption cycle.
32.	Uppalapati, Suji, et al. (författare) Photochemical Reactions of Poly(4-vinylphenol) Thin Films 2010 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 211:4, s. 461-470 Tidskriftsartikel (refereegranskat)abstract The mechanism involved in the photochemical immobilization of poly (4-vinylphenol) (PVP) thin. films was investigated. The films were fabricated by a simple procedure of UV irradiation and solvent extraction. A combination of ellipsometry, IR, and high-resolution X-ray photoelectron spectroscopy (XPS) was used to provide detailed and quantitative analysis of the composition of the photochemical reaction products. Upon irradiation at 260 nm, benzyl and phenoxy radicals are generated in the polymer. In the absence of oxygen, PVP films crosslinked via the combination of the benzyl radicals or phenoxy radicals. At lower irradiation doses, the photochemical process was dominated by cross-linking of the polymer backbone via the combination of benzyl radicals. At higher exposure doses, cross-linked quinoid structures were generated, and the concentration increased with the irradiation time. No oxidation or degradation products were observed. In the presence of oxygen, additional reactions of oxidation and degradation occurred. At lower doses, oxidation at the benzyl position produced the ketone structure evidenced by the drastic increase in the 0 content in the irradiated films. As the irradiation doses increased, further oxidation at the methylene position occurred, and in addition, volatile and degradation products were also generated. This photochemical process was successfully employed to fabricate patterned PVP structures.
33.	Valencia, Luis, et al. (författare) Tuning the LCST of PNIPAM via Random Oxidation-Sensitive Thioether Functionalities 2017 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 218:9 Tidskriftsartikel (refereegranskat)abstract In this work, an oxidation-responsive thioether-functionalized poly(N-isopropylacrylamide) is reported, which is synthesized via reversible-addition fragmentation transfer (RAFT) polymerization using 6-(methylthio)hexyl acrylate or 2-(methylthio)ethyl acrylate as comonomers and S-ethyl-S-(a,a-dimethyl-a-acetic acid)trithiocarbonate as RAFT agent, investigating the influence over the lower critical solution temperature (LCST) of the random thioether functionalities, prior and upon oxidation. The hydrophobic thioethers shift the LCST values of the resulting copolymers to very low temperatures, but the value could be regulated upon oxidation due to the huge increase in dipolar moment. The resulting copolymers containing hydrophilic sulfoxides show much higher LCST values, reaching a difference of up to 23 degrees C after oxidation. Results are supported by H-1 NMR, size exclusion chromatography, and turbidimetry measurements.
34.	Woo, Euntaek, et al. (författare) Polyimide‐PEG Segmented Block Copolymer Membranes with High Proton Conductivity by Improving Bicontinuous Nanostructure of Ionic Liquid‐Doped Films 2019 Ingår i: Macromolecular Chemistry and Physics. - : Wiley-Blackwell Publishing Inc.. - 1022-1352 .- 1521-3935. ; 220:9 Tidskriftsartikel (refereegranskat)abstract The structure and properties of segmented block copolymer films of aromatic polyimide (PI) and poly(ethylene glycol) (PEG) doped with an ionic liquid are studied for potential polymer electrolyte membrane applications for fuel cells. Poly(amic acid) precursors of PI-PEG copolymers of 4,4-(hexafluoroisopropylidene) diphthalic anhydride, 4,4-(1,3-phenylenedioxy) dianiline, and bis(3-aminopropyl) terminated PEG (M-n approximate to 1500) are synthesized and then thermally imidized in membrane films, followed by swelling in ethylammonium nitrate (EAN) ionic liquid. The small-angle X-ray scattering results from the EAN-doped PI-PEG copolymer films show disordered bicontinuous phase-separated nanostructures described by Teubner-Strey theory, with the interface fractal dimension determined from the Porod equation. Thermal annealing of the EAN-doped membranes at 100-140 degrees C results in increased correlation lengths and smoother interfaces of the bicontinuous nanostructures. Such improved nanostructures lead to the increased ionic conductivity by two to five times with the maximum conductivity of 210 mS cm(-1) at 60 degrees C and 70% RH, much greater (nearly fivefold) than that of Nafion films, while maintaining the mechanical stability possibly up to 140 degrees C. Moreover, the investigation of the disordered bicontinuous phase-separated nanostructure of EAN-doped PI-PEG copolymer membranes is highly relevant to understanding the nanostructures of hydrated Nafion membranes and segmented block copolymers in general.
35.	Xu, Huan, et al. (författare) Stereocontrolled Entanglement-Directed Self-Alignment of Poly(lactic acid) Cylindrites 2016 Ingår i: Macromolecular Chemistry and Physics. - : John Wiley & Sons. - 1022-1352 .- 1521-3935. ; 217:23, s. 2567-2575 Tidskriftsartikel (refereegranskat)abstract The concept of stereocontrolled entanglements, in which the tunable H-bonded chiral pairs serve as crosslinks to create topological constraints on the local chain dynamics, is introduced to tailor the crystalline morphology of stereocomplex poly(lactic acid). For the entanglements to be interconnected and activated, poly(d-lactic acid) with statistical branched architecture is incorporated, enabling the construction of 3D association with linear poly(l-lactic acid) chains. With thermodynamically graded disentanglement relaxation for the blends, the profound influence of entanglements on the crystalline morphology is revealed during isothermal crystallization. Orderly aligned cylindrites some with an exceptional length of over 500 μm, resembling the structural features of the classical shish-kebab superstructure, are observed in the blends penetrated with dense entanglement constraints. By contrast, only dendritic spherulites are formed in the highly disentangled blends. The selectively suppressed homo-crystallization by the entanglements offers insights into the contribution of constraints. This bottom-up strategy opens up pathways to engender oriented crystals of long-range order under quiescent conditions, which has potential implications for other chiral polymers.
36.	Yushmanov, Pavel, et al. (författare) Kinetics of demixing and remixing transitions in aqueous solutions of poly(N-isopropylacrylamide) : A temperature-jump H-1 NMR study 2006 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 207:21, s. 1972-1979 Tidskriftsartikel (refereegranskat)abstract The time course of the coil-to-globule collapse and intermolecular aggregation of poly(N-isopropylacrylamide) in aqueous solution upon exceeding the lower critical solution temperature (LCST) are investigated by temperature-jump 1H NMR spectroscopy. After the temperature jump, we record the time dependences of (i) the mobile fraction of the polymer chain as revealed by the intensity of the liquid-like NMR signal, (ii) the local mobility of those chains as revealed by the transverse relaxation time T2, and (iii) their self-diffusion coefficient D. The same data are also reported at their temperature-dependent long-time limits. The results suggest a sudden, faster than one second, collapse and intermolecular aggregation into globules and a slower reorganization/redistribution of the individual chains among and within the globular and mobile states. We found that all molecular changes are reversible if the temperature remains less than ca. 6-8 K above the LCST for less than a few minutes; under those conditions, experiments upon sudden temperature quench below the LCST show that the aggregates disintegrate and swell into coils in less than a few seconds.
37.	Zhu, Jiahua, et al. (författare) Interface-strengthened polyimide/carbon nanofibers nanocomposites with superior mechanical and tribological properties 2014 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352 .- 1521-3935. ; 215:14, s. 1407-1414 Tidskriftsartikel (refereegranskat)abstract A self-assembling molecule, n-octadecane phosphate, is successfully synthesized and used to modify the surface property of carbon nanofibers (CNFs). Both untreated CNFs (CNFs(u)) and treated CNFs (CNFs(t)) are incorporated in polyimide (PI) as filler to study the interfacialproperty-determined thermal, mechanical, and tribological properties of their corresponding nanocomposites. At room temperature, the mechanical properties of PI/CNFs(t) including elongation-to-break, tensile strength, bending strength, and impact strength are remarkably improved by 150%, 29.4%, 26.7%, and 183%, respectively, in comparison with the PI/CNFs(u) composites. At 150 °C, the enhancement of the elongation-to-break reaches 250%, while the tensile and flexural-strength enhancement reduce to 2.8% and 20.4%. In addition, the tribological properties of PI/CNFs(t) composite are also improved due to the better interfacial interaction between the filler and the matrix. Microstructure analysis of the fracture surface directly reveals the better dispersion quality of CNFs(t) in PI and superior interfacial adhesion with the introduced assembling layer.
38.	Öjelund, K, et al. (författare) Synthesis, Structure and Properties of MelamineB pTHF-Urethane Supramolecular Compounds. 2003 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1521-3935 .- 1022-1352. ; 204:1, s. 52-60 Tidskriftsartikel (refereegranskat)abstract The properties of melamine based supramolecular compounds have been studied with rheological, thermal, mechanical, dielectric and scattering techniques and compared with similar covalently bonded materials. The complexes are based on a linear pTHF-diol ([bar M ]n = 1 000) connected via a diisocyanate with melamine. The results obtained show that, despite of the material's low molecular weight (< 2 000 g · mol-1), it has properties typical for high molar mass polymers. The material has a high modulus above the glass transition temperature, and shows behavior similar to a semi-crystalline material. This is attributed to the presence of the hydrogen bonds, in combination with phase separation giving rise to hard domain formation. In comparison with a covalently bonded and a low molecular weight material of similar composition, the supramolecular compounds have a higher and more temperature dependent viscosity. By exchanging parts of the pTHF with a low molecular weight diol, in our case hexane diol, the mechanical properties at room temperature could be modified to a stiffer but more brittle material.
39.	Karlsson, Lina, et al. (författare) Preparation and solution properties of amphiphilic sulfonated acrylamide copolymers 2002 Ingår i: Macromolecular Chemistry and Physics. - 1521-3935. ; 203:4, s. 686-694 Tidskriftsartikel (refereegranskat)abstract Copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and N-tert-butylacryl-amide has been carried out in methanol at 60degreesC using AIBN as initiator. Both IR and H-1 NMR spectroscopy indicated that monomer conversions exceeding 95% were reached in the copolymerizations. Copolymers containing more or equal to approximate to 15 mol-% AMPS were soluble in water and had an amphiphilic character. Analysis by dilute solution viscometry, quasi-elastic light scattering, and size exclusion chromatography in water and aqueous KCl solution showed that the AMPS homopolymer and the copolymers behave as polyelectrolytes. Light scattering analysis and atomic force microscopy indicated the presence of aggregates in aqueous solutions of a copolymer containing 15 mol-% AMPS. Gravimetrical measurements showed that the water absorption of the copolymers in humidified air increases almost linearly with the AMPS content of the copolymers.
40.	Andrzejewska, E, et al. (författare) The role of oxygen in camphorquinone-initiated photopolymerization 1998 Ingår i: MACROMOLECULAR CHEMISTRY AND PHYSICS. - 1022-1352. ; 199:3, s. 441-449 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
41.	Bagan Navarro, Hector, et al. (författare) Thermoresponsive Polymer Brushes on Organic Microspheres for Biomolecular Separation and Immobilization 2017 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352. ; 218:3 Tidskriftsartikel (refereegranskat)abstract A new method is developed to synthesize organic microsphere-supported polymer brushes for affinity separation of saccharides and glycoproteins. In the first step, crosslinked polymer microspheres are synthesized using atom transfer radical polymerization (ATRP). The terminal ATRP initiators on the microspheres are used to graft polymer brushes from propargyl acrylate and N-isopropyl acrylamide. The microsphere-supported polymer brushes are conjugated with an azide-tagged phenylboronic acid to complete the material synthesis. The microsphere-supported, boronic acid-containing polymer brushes are able to bind not only low molecular weight cis-diol compounds but also glycoproteins. The synthetic procedure developed in this work provides a convenient means for preparing all-organic microsphere-supported polymer brushes that have high alkaline stability. Using the surface-attached polymer brushes to immobilize a catalytic glycoprotein (horseradish peroxidase), it is possible to retain on-particle enzyme activity due to the open structure of the polymer brushes and the oriented immobilization. (Figure presented.).
42.	Jiang, Lingdong, et al. (författare) Temperature and pH Controlled Self-Assembly of a Protein-Polymer Biohybrid 2018 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352. ; 219:7 Tidskriftsartikel (refereegranskat)abstract A novel pH and temperature dual-responsive bioconjugate is prepared by grafting thermoresponsive polymer chains from a pH-responsive protein amelogenin via atom transfer radical polymerization. To the best of our knowledge, this is the first time that amelogenin is exploited to prepare a hybrid biomaterial with new stimuli-responsive property. In both basic and acidic solutions the protein-polymer bioconjugate is able to self-assemble into uniform and stable nanoparticles when heated to above the lower critical solution temperature of the polymer. The amelogenin-based stimuli-responsive bioconjugate may be of great use in the fields of bioseparation and drug/gene delivery, and the synthetic approach reported here should provide a convenient means to preparing amelogenin-based functional biohybrid materials.
43.	Nie, J, et al. (författare) Effect of peroxides and hydroperoxides on the camphorquinone-initiated photopolymerization 1999 Ingår i: MACROMOLECULAR CHEMISTRY AND PHYSICS. - 1022-1352. ; 200:7, s. 1692-1701 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
44.	Tas, Sinem, et al. (författare) Chain End-Functionalized Polymer Brushes with Switchable Fluorescence Response 2019 Ingår i: Macromolecular Chemistry and Physics. - : Wiley. - 1022-1352. ; 220:5 Tidskriftsartikel (refereegranskat)abstract Herein is described the switchable fluorescence response of poly(methyl methacrylate) (PMMA) brushes. Chain end fluorescein labeled PMMA brushes are prepared by combining surface-initiated atom transfer radical polymerization (SI-ATRP) with a copper-catalyzed alkyne-azide cycloaddition (CuAAC) click reaction. Successful attachment of fluorescein is confirmed by measuring fluorescence of the as-prepared films. Utilizing co-solvency of PMMA in isopropanol-water mixtures, responsive behavior of the end-functionalized brushes is demonstrated by measuring the changes in fluorescence intensity between the swollen and collapsed states.

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