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- Gathergood, Nicholas
(creator_code:cre_t)
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Synthesis and polymerization of isosorbide-based monomethacrylates
- 2019
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Patent (övrigt vetenskapligt/konstnärligt)abstract
- Isosorbide-5-methacrylate was obtained by enzymatic catalysis with Lipozyme RM IM in a highly regioselective manner in up to 87% yield. The process uses readily available acyl donors (methacrylic anydride or vinyl methacrylate), is easily scalable and chromatography free. Simple extractive workup followed by decoloration and filtration affords the monomer with up to > 99% purity. In addition, the developed enzymatic strategy was applied for the synthesis of a series of isosorbide 5- and 2-methacrylate derivatives. All the sythesized isosorbide monomethacrylates were radically polymerized with AIBN. The properties of these polymers with different side groups in either endo or exo configuration in the isosorbide structure was examined. The methacrylic isosorbide derivatives with OH-group were found to have very high glass transition temperature (Tg = 167 °C) and good thermal stability (at 5% weight loss under N2, Td,95 = 240 °C). The highest molecular weight (Mn = 80.6 kg/mol) was determined for the polymethacrylate with Ac-substitute.
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- Laanesoo, Siim, et al.
(författare)
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Poly(alkanoyl isosorbide methacrylate)s: from amorphous to semi-crystalline and liquid crystalline biobased materials
- 2021
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1526-4602 .- 1525-7797. ; 22:2, s. 640-648
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Tidskriftsartikel (refereegranskat)abstract
- We have prepared a series of twelve D-isosorbide-2-alkanoate-5-methacrylate monomers as single regioisomers with different pendant linear C2 to C20 alkanoyl chains by using biocatalytic and chemical acylations. By conventional radical polymerization, these monomers afforded high-molecular weight biobased poly(alkanoyl isosorbide methacrylate)s (PAIMAs). Samples with C2-C12 alkanoyl chains were amorphous with glass transition temperatures from 107 to 54 °C, while C14-C20 chains gave semi-crystalline materials with melting points up to 59 °C. Moreover, PAIMAs with C13-C20 chains formed liquid crystalline mesophases with transition temperatures up to 93 °C. The mesophases were studied by polarized optical microscopy, and rheology showed stepwise changes of the viscosity at the transition temperature. Unexpectedly, a PAIMA prepared from a regioisomeric monomer (C18) showed semi-crystallinity but no liquid crystallinity. Consequently, the properties of the PAIMAs were readily tunable by controlling the phase structure and transitions through the alkanoyl chain length and the regiochemistry to form fully amorphous, semi-crystalline or semi-/liquid crystalline materials.
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- Matt, Livia, et al.
(författare)
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Enzymatic synthesis and polymerization of isosorbide-based monomethacrylates for high-Tg plastics
- 2018
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Ingår i: ACS Sustainable Chemistry & Engineering. - : American Chemical Society (ACS). - 2168-0485. ; 6:12, s. 17382-17390
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Tidskriftsartikel (refereegranskat)abstract
- Isosorbide is a stiff bicyclic diol derived from glycose-based polysaccharides, and is thus an attractive building block for novel rigid bioplastics. In the present work a highly regioselective biocatalytic approach for the synthesis of isosorbide 5-methacrylate was developed. The Lipozyme RM IM (Rhizomucor miehei lipase) catalyzed process is straightforward, easily scalable and chromatography-free; a simple extractive workup afforded the monomer at >99% purity and in 87% yield. The developed strategy was applied for the synthesis of a series of monomethacrylated isosorbide derivatives. Radical polymerization of the monomers produced rigid polymethacrylates with a certain side group in either endo or exo configuration, exclusively, which generated materials with great diversity of properties. For example, the two regioisomeric polymers carrying hydroxyl groups reached a glass transition temperature at Tg = 167 °C. The polymer tethered with dodecanoate chains in exo position showed crystallinity with an unexpectedly high melting point at Tm = 83 °C. In contrast, the corresponding sample with dodecanoate chains in endo positions was fully amorphous with Tg = 54 °C. Efficient biocatalytic synthesis combined with attractive polymer properties opens up possibilities for production of these bio-based polymers on an industrial scale.
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