A new six‐membered cyclic carbonate monomer, 5‐benzyloxy‐trimethylene carbonate, was synthesized from 2‐benzyloxy‐1,3‐propanediol, and the corresponding polycarbonate, poly(5‐benzyloxy‐trimethylene carbonate) (PBTMC), was further synthesized by ring‐opening polymerization in bulk at 150 °C using aluminum isobutoxide [Al(OiBu)3], aluminum isopropoxide, or stannous octanoate as an initiator. The results showed that a higher molecular weight polycarbonate could be obtained in the case of Al(OiBu)3. The protecting benzyl group was removed subsequently by catalytic hydrogenation to give a polycarbonate containing a pendant hydroxyl group (PHTMC). The polycarbonates obtained were characterized by Fourier transform infrared spectroscopy, 1H NMR,13C NMR, gel permeation chromatography, and DSC. NMR results of PBTMC offered no evidence for decarboxylation occurring during the propagation. The pendant hydroxyl group in PHTMC resulted in an enhancement of the hydrophilicity of the polycarbonate. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 70–75, 2002

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Poly(L-lactide) and poly(ε-caprolactone) (PLLA/PCL) blends with various weight ratios were compounded by melt mixing and their shape memory properties were investigated. The thermal properties, surface morphology and dynamic mechanical properties of the blends were characterized. The results demonstrate that the introduction of PCL improves the process of crystallization of PLLA whereas the reverse situation is for PCL. PLLA/PCL blends were found to exhibit an immiscible behavior from the characterizations of surface morphology. DMA tests show the blends with different weight ratios have different transition temperatures. The properties of blends provide the basis of owning shape memory behavior. The strain recovery ratio (Rr) of PLLA/PCL blend with the weight ratio of 1:3 was about 95% within 22s, whereas the Rr of other blends were less than 75% within 23~30s. It was found that lower transition temperature combined with increased crystallization of PLLA with the increasing PCL content contribute to such a good shape memory effect.

A series of aliphatic poly(carbonate-co-phosphate)s was synthesized in bulk using aluminium isopropoxide as initiator by ring-opening polymerization with various cyclic carbonates (trimethylene carbonate (TMC) and 5,5-dimethyltrimethylene carbonate (DTC)) and cyclic phosphates (ethylene ethyl phosphate (EEP), ethylene isobutyl phosphate (EIBP), ethylene lauryl phosphate (ELP) and ethylene stearyl phosphate (ESP)). The in¯uence of reaction conditions such as polymerization time, polymerization temperature and initiator concentration on the yield and molecular weight were investigated. The substituent effect of the cyclic monomers on the polymerization was also studied, and the results indicate that the substituents exert a marked in¯uence on the molecular weight of the copolymers obtained. The comonomer reactivity ratios were determined (TMC 0.88 and EEP 1.17). The copolymers with backbone chains rich in phosphate content exhibit better hydrophilicity than that of TMC homopolymer, and the degradation rate of the copolymers increases with the increase of phosphate content therein.

This paper is concerned with the relationship between the industry structure and discipline structure of higher education in Fujian province of China. It draws on the data about the industry structure from the Fujian Statistical Yearbook (2005-2012) and the data about the discipline structure from Fujian Education Statistical Yearbook (1949-2012). After correlation analysis and comparison analysis between the industry structure in the GDP value and the labor in Fujian Province from 2005-2012 and the discipline structure in Fujian’s universities and colleges from2005-2012, this article concludes that the industry structure decides the discipline structure of higher education in a district and the discipline structure also affects the industry structure, and for the universities and colleges in Fujian Province, they should pay more attention to the development of engineering programs, increase the enrollment of them and relatively decrease the enrollment of the art students.