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Chinese Journal of Polymer Science 2016年第11期34卷 1330-1338页

作者： Fan Liu Li-li Mei Zhi-lin Tan 鄢国平 Jun-fang Guo Qiao Zhang Hui Liu Jun Yang School of Material Science and Engineering Wuhan Institute of TechnologyWuhan 430074China

Poly（9-phenyl-2,4,8,10-tetraoxaspiro-[5,5]undcane-3-one）（PPTC） was synthesized by the microwave-assisted ring-opening polymerization （MROP） of a six-membered cyclic carbonate monomer 9-phenyl-2,4,8,10-tetraoxaspiro- [5,5]undcane-3-one （PTC） with tin（Ⅱ） 2-ethylhexanoate （Sn（Oct）2） or aluminum isopropoxide （Al（OiPr）3） as the catalysts. The obtained polycarbonates were further reduced by apalladium/carbonate catalyst （10% Pd/C） to afford partly deprotected polycarbonates containing hydroxyl groups （HPPTC）. These two types of polycarbonates were characterized by ^1H-NMR, Fourier transform infrared spectroscopy （FTIR）, UV, gel permeation chromatography （GPC）, differential scanning calorimetry （DSC）, and automatic contact-angle measurements. The influence of the feed molar ratio of monomer-to-catalyst, the microwave irradiation power and the reaction time on the polymerization was also studied. The experimental results showed that HPPTC possessed significantly higher hydrophilicity.and water absorption rate than PPTC.

关键词： Biodegradable polycarbonate Microwave-assisted polymerization Ring-opening polymerization hydrophilicity.

CORRELATION OF SiOx LAYER THICKNESS AND PROPERTIES OF BOPP/SiOx COMPOSITE FILMS WITH SPIN COATING PROCESS PARAMETERS

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Chinese Journal of Polymer Science 2013年第2期31卷 333-345页

作者： Xiao-li Yao 马育红 Chang-wen Zhao 杨万泰 Key Laboratory of Carbon Fiber and Functional Polymers Ministry of EducationBeijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

The effects of the spin coating process parameters on the thickness of the SiOx layer of the BOPP/SiOx composite film were investigated. When the concentration of tetraethoxysilane （TEOS） increased from 12.5 vol% to 55% vol%, the SiOx thickness increased from about 80 nm to 470 nm. In the sol time range of 1.5 h to 5 h the SiOx layer thickness reached a maximum at about 4 h and the change of the thickness roughly matched the change of the silica colloidal sphere sizes in sol. When the spin-coating speed of the dispensing stage increased from 450 r/min to 500 r/min, the SiOx layer thickness drastically decreased from about 1.67 gm to 400 nm. While the spin-coating speed of the thinning and drying stage went up to 1200 r/min, the SiOx layer thickness was in the range of 330 nm to 390 nm. It was also found that the SiOx layer thickness was almost increased linearly from about 500 nm to 1.02 gm with the ratio of the commercial silica colloidal to the TEOS from 0.2 to 1.0. The water contact angles decreased to about 23.0° for the BOPP/Si-Sol composite film with 1.67 μm SiOx layer and about 4.0° for the BOPP/mixing Si-Sol composite film with 1.02 μm SiOx layer. Compared to BOPP, the light transparency of the BOPP/Si-Sol composite films decreased by about 5.5% with the SiOx layer from about 80 nm to 1.67 μm and by 7.0% for the BOPP/mixing Si-Sol composite film with the SiOx layer from about 350 nm to 1.02 μm respectively.

关键词： Composites Polypropylene Silicas Spin-coating hydrophilicity.

Poly(L-lactide)-Poly(ethylene glycol) Multiblock Copolymers: Synthesis and Properties

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Chinese Chemical Letters 2002年第1期13卷 33-36页

作者： Wei Jun LUO Su Ming LI Jian Zhong BEI Shen Guo WANG Center fpr Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

Poly (L-lactide)-poly(ethylene glycol) multiblock copolymers with predetermined block lengths were synthesized by polycondensation of PLA diols and PEG diacids. These copolymers presented special properties, such as better miscibility between the two components, low crystallinity and better hydrophilicity. which can be modulated by adjusting the block lengths of the two components.

关键词： Poly (L-lactide) poly(ethylene glycol) biodegradability multiblock copolymer miscibility crystallinity hydrophilicity.

Effects of COOH^+ ion implantation on hemocompatibility of polypropylene

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Science China(Technological Sciences) 2002年第6期45卷 666-670页

作者：李德军牛丽芳 Department of Physics Tianjin Normal University Tianjin 300074 China

Carboxyl ion (COOH+) implantation was performed at 50 keV with different fluences for polypropylene. Hemocompatibility tests show that blood coagulation time and recalcification time of polypropylene were enhanced significantly with the increasing fluence. At the same time, the human endothelial cells grown on the surface of the implanted samples exhibited normal cellular growth and morphology. X-ray photoelectron spectroscopy and water contact angle analysis showed that COOH+ ion implantation rearranges chemical bonds and produces some new polar O-containing groups on the surface. The formation of polar functional groups, together with increase of roughness, induced an increase in hydrophilicity. which in turn improved the surface hemocompatibility of polypropylene.

关键词： polypropylene, ion implantation, hemocompatibility, hydrophilicity.

STUDY ON SIDE REACTION IN THE SYNTHESIS OF HYPERCROSSLINKED POLYMERS

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Chinese Journal of Reactive Polymers 2008年第1期17卷 12-17页

作者： ZHANG Bo LI Aimin TAO Weihua YANG Weiben State Key Laboratory of Pollution Control and Resource Reuse School of Environment Nanjing University Nanjing 210093 China College of Chemistry and Environmental Science Nanjing Normal University Nanjing 210046 China

The systematical study about side reactions have revealed the formation mechanism of oxygen-containing groups of hypercrosslinked polymers. Surface chemistry and functionality of the polymers are characterized by Fourier-transform infrared spectroscopy (FT-IR), solid state nuclear magnetic resonance (NMR) and contact angle. The results showed that the ether groups were from chloromethylated reaction, and the alcohol groups arose from partial hydrolysis of chloromethyl groups during the post-crosslinking reaction, and the carbonyl functionality was formed by further oxidation of the alcohol groups. Catalyst and solvent used in the postcrosslinking reaction would greatly influence the surface chemistry of the polymer.

关键词： Hypercrosslinked polymer Surface chemistry Oxygen-containing groups hydrophilicity.

STUDY ON SIDE REACTION IN THE SYNTHESIS OF HYPERCROSSLINKED POLYMERS

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Chinese Journal of Reactive Polymers 2008年第Z1期 12-17页

作者： ZHANG Bo1 LI Aimin1 TAO Weihua1 YANG Weiben2 1. State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210093, China 2. College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210046, China

关键词： Hypercrosslinked polymer Surface chemistry Oxygen-containing groups hydrophilicity.