The utilization of wood-derived building blocks (xylochemicals) to replace fossil-based precursors is an attractive research subject of modern polymer science. Here, we demonstrate that bisguaiacol (BG), a lignin-derived bisphenol analogue, can be used to prepare biobased polyesters with remarkable thermal properties. BG was treated with different activated diacids to investigate the effect of co-monomer structures on the physical properties of the products. Namely, derivatives of adipic acid, succinic acid, and 2,5-furandicarboxylic acid were used. Moreover, a terephthalic acid derivative was used for comparison purposes. The products were characterized by H NMR spectroscopy, attenuated total reflectance FTIR spectroscopy, gel-permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry to assess their structural and thermal properties in detail. The polymers showed glass-transition temperatures ranging up to 160 °C and thermal stabilities in excess of 300 °C. Furthermore, the susceptibility of the polyester to enzymatic hydrolysis was investigated to assess the potential for further surface functionalization and/or recycling and biodegradation. Indeed, hydrolysis with two different enzymes from the bacteria Thermobifida cellulosilytica led to the release of monomers, as quantified by HPLC. The results of this study indicate that our new polyesters represent promising renewable and biodegradable alternatives to petroleum-based polyesters currently employed in the plastics industry, specifically for applications in which high-temperature stability is essential to ensure overall system integrity.

(2015) High-pressure rheological analysis of CO2-induced melting point depression and viscosity reduction of poly(ε-caprolactone). Polymer, Access from the University of Nottingham repository: http://eprints.nottingham.ac.uk/45413/1/curia_polymer2015_preprint.pdf Copyright and reuse:The Nottingham ePrints service makes this work by researchers of the University of Nottingham available open access under the following conditions. This article is made available under the Creative Commons Attribution Non-commercial No Derivatives licence and may be reused according to the conditions of the licence. For more details see: http://creativecommons.org/licenses/by-nc-nd/2.5/ A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. Furthermore, a significant decrease in the viscosity of two PCL grades with different molecular weight (M n~1 0 kDa and 80 kDa) was also detected upon increasing the CO 2 pressure to 300 bar.Experimental viscosity data were fitted to the Carreau model to quantify the extent of the plasticising effects on the zero-shear viscosity and relaxation time under different conditions. Similar analyses were conducted under high-pressure nitrogen, to compare the effects obtained in the presence of a non-plasticising gas.

The use of naturally available building blocks for the preparation of high-performance polymers is attracting increasing interest. Betulin (or betulinol) is a naturally occurring, large, nonaromatic diol with a pentacyclic ring structure that can be extracted in high percentages from the bark of birch trees. Here we demonstrate that betulin can be used to prepare polyesters with exceptional thermal attributes through industrially viable and scalable melt polycondensation reactions. Specifically, betulin-based thermoplastics were synthesized using succinic acid, adipic acid, 1,12-dodecanedioic acid, and 1,18-octadecanedioic acid as comonomers and showed good solubility in common industrial solvents. Additionally, betulin-based polyester thermosets were formulated via the incorporation of glycerol as a cross-linker. A systematic study evaluating the effect of various comonomers on the structure−property relationships of these betulin-derived thermoplastics (M w s ranging from 7500 g mol −1 to about 60,000 g mol −1 ) and thermosets (E′ at room temperature ranging from 2.0 to 780 MPa) reveals that betulin is a renewable and versatile platform chemical for the preparation of high-performance polymeric materials. Indeed, these materials displayed glass transition temperatures ranging from 20 °C to about 215 °C, thermal stabilities in excess of 300 °C in both N 2 and air, and Young's moduli and tensile strengths exceeding 600 MPa and 9 MPa, respectively. These investigations provide new insights into the rational design of approaches toward betulin-based products for high-performance polymer applications.

Curia, Silvio and Howdle, Steven M. (2016) Towards sustainable polymeric nano-carriers and surfactants: facile low temperature enzymatic synthesis of bio-based amphiphilic copolymers in scCO2. Polymer Chemistry . ISSN 1759-9962 Access from the University of Nottingham repository: http://eprints.nottingham.ac.uk/31958/1/MPEG-PHAz%20paper%20revised%20v2.pdf Copyright and reuse:The Nottingham ePrints service makes this work by researchers of the University of Nottingham available open access under the following conditions. This article is made available under the University of Nottingham End User licence and may be reused according to the conditions of the licence. For more details see: http://eprints.nottingham.ac.uk/end_user_agreement.pdf A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. We demonstrate that useful bio-based amphiphilic polymers can be produced enzymatically at a 13 mild temperature, in a solvent-free system and using renewably sourced monomers, by exploiting 14 the unique properties of supercritical CO 2 (scCO 2 ). We present the use of a novel near-ambient 15 temperature approach to prepare renewable amphiphilic ABA copolymers in scCO 2 . Bio-based 16 commercially available monomers have been polymerised to prepare chains with targeted molecular 17 weight. The amphiphilic materials were prepared by end-capping the synthesised polymers with 18 methoxy poly(ethylene glycol) (MPEG) chains in a one-pot high pressure reaction utilising 19Candida Antarctica Lipase B (CaLB) as a catalyst at a temperature as low as 35 °C. 20The block copolymers are characterised by 1 H-NMR, GPC and DSC in order to carefully assess 21 their structural and thermal properties. These polymers form self-assembled aggregates in aqueous 22 environment and these nanostructures are studied through DLS, TEM and UV-Vis. Highly 23 hydrophobic Coumarin-6 was used as a model to prove dispersion in water of lipophilic molecules. 24Maximum bubble pressure tests demonstrate the reduction in surface tension of these polymers and 25 comparisons are made directly to commercial polymeric non-ionic surfactants. The large-scale production of amphiphilic block copolymers began in the 1950s, and these 32 interesting macromolecules continue to attract considerable attention. [1][2][3][4][5] Amphiphilic block 33 copolymers form nanostructures (e.g. micelles and vesicles) that can find application as drug 34 encapsulation and delivery systems and also in formulations as wetting agents, compatibilisers, 35 emulsifiers and detergents. [1][2][3][5][6][7][8][9][10][11][12][13][14] For example, polymeric micelles are characterised by a core-shell 36 structure and have emerged as potential carriers for highly hydrophobic molecules because these 37 can be encapsulated in the l...