“In-situ” lipase-catalyzed cotton coating with polyesters from ethylene glycol and glycerol

"Available online 12 January 2018"Several polyesters were synthesized from ethylene glycol, glycerol and adipate, succinate dimethyl esters. Immobilized Candida antarctica lipase B was used as catalyst for 6hours under vacuum at 70°C without any further solvents. The highest conversion rate of 88.5% occurred for the polymerization of poly (ethylene adipate), evaluated by 1H NMR. MALDI-TOF analysis indicated that most of the oligomers formed were dimers or trimers. After successfully synthesize the polyesters we set-up the optimal conditions for their in-situ coating onto cotton substrates with a soluble lipase from Thermomyces lanuginosus. This work presents a novel bio-approach to impart hydrophobic properties to coated cotton-based fiber materials.This work was supported by Chinese government scholarship under the State Scholarship Fund (grant number 201706790049), Jiangsu Province Scientific Research Innovation Project for Academic Graduate Students (grant number KYLX16_0788), Training Fund for Excellent Doctoral Student in Jiangnan University, Key Projects of governmental cooperation in international scientific and technological innovation (grant number 2016 YFE0115700) and the National Key R & D Program of China (grant number 2017 YFB0309100). This work was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (grant number POCI-01-0145-FEDER-006684) and under the Project RECI/BBB-EBI/0179/2012 (grant number FCOMP01-0124-FEDER-027462). This study was also supported by BioTecNorte operation (grant number NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte. This work was also supported by the National Natural Science Foundation of China (grant number 31470509 and 31201134), the Industry-Academic Joint Technological Prospective Fund Project of Jiangsu Province (grant number BY2013015-24 and BY2016022-23), the fundamental research funds for the central universities (grant number JUSRP 51622A), and a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.info:eu-repo/semantics/publishedVersio

Multiblock polyesters demonstrating high elasticity and shape memory effects

Polyester block polymers containing polylactide have garnered significant attention as renewable, degradable alternatives to traditional elastomers. However, the low glass transition of the PLA blocks limits the upper-use temperatures of the resulting elastomers. To improve the thermal performance, we explore a series of multiblock polyesters composed of poly(ε-decalactone) (PDL) and poly(cyclohexene phthalate) (PCHPE). These materials are prepared using switchable polymerization catalysis followed by chain extension. The strategy involves (i) alternating ring-opening copolymerization (ROCOP) of cyclohexene oxide and phthalic anhydride, (ii) ε-decalactone ring-opening polymerization (ROP), and (iii) diisocyanate coupling of the telechelic triblocks to increase molar mass. The resulting multiblock polyesters are amorphous, and the blocks are phase separated; glass transition temperatures are ∼−45 and 100 °C. They show thermal resistance to mass loss with Td5% ∼ 285 °C and higher upper use temperatures compared to alternative aliphatic polyesters. The nanoscale phase behavior and correlated mechanical properties are highly sensitive to the block composition. The sample containing PCHPE = 26 wt % behaves as a thermoplastic elastomer with high elongation at break (εb > 2450%), moderate tensile strength (σb = 12 MPa), and low residual strain (εr ∼ 4%). It shows elastomeric behavior from −20 to 100 °C and has a processing temperature range of ∼170 °C. At higher PCHPE content (59 wt %), the material has shape memory character with high strain fixation (250%) and recovery (96%) over multiple (25) recovery cycles. The multiblock polyesters are straightforward to prepare, and the methods presented here can be extended to produce a wide range of new materials using a other epoxides, anhydrides, and lactones. This first report on the thermal and mechanical properties highlights the significant potential for this class of polyesters as elastomers, rigid plastics, and shape memory materials

Block copolymer morphologies in dye-sensitized solar cells: Probing the photovoltaic structure-function relation

We integrate mesostructured titania arrays into dye-sensitized solar cells by replicating ordered, oriented one-dimensional (1D) columnar and three-dimensional (3D) bicontinuous gyroid block copolymer phases. The solar cell performance, charge transport, and recombination are investigated. We observe faster charge transport in 1D "wires" than through 3D gyroid arrays. However, owing to their structural instability, the surface area of the wire arrays is low, inhibiting the solar cell performance. The gyroid morphology, on the other hand, outperforms the current state-of-the-art mesoporous nanoparticle films. © 2009 American Chemical Society