The synthesis of new porous copolymers for chromatography purposes is presented. They are formed during the suspension and emulsion polymerization of methacrylate derivatives of bisphenol-S with divinylbenzene in the presence of the pore-forming diluent. One type of the obtained copolymers contains
Synthesis and characterization of polycarbonates based on bisphenol S by melt transesterification
β Scribed by Der-Jang Liaw; Ping Chang
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 169 KB
- Volume
- 35
- Category
- Article
- ISSN
- 0887-624X
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β¦ Synopsis
Several sulfone-containing polycarbonates, having inherent viscosity 0.25-0.30 dL g 01 in N,N-dimethylformamide (DMF), were prepared by melt polycondensation of diphenyl carbonate (DPC) with various aromatic and aliphatic diols, in the presence of zinc acetate as transesterification catalyst. The polycarbonates were examined with IR spectra, inherent viscosity, solubility, tensile strength, contact angle, DSC and TGA. Almost all polymers were soluble in DMF, pyridine, N-methyl pyrrolidinone (NMP), THF, phenol and dimethylsulfoxide (DMSO), partially soluble in nitrobenzene, but insoluble in acetone. Polycarbonate with introduced ether linkages leads to enhanced flexibility and elongation strength. The contact angle of the polycarbonate based on bisphenol S was found in the range 42-80Π, smaller than that of polycarbonates based on bisphenol AF and bisphenol A. The wettability of polycarbonate films based on bisphenol S remarkably increased with increasing oxyethylene unit in polymer chain. The smaller values of T d of PC-3-PC-7 than of PC-1 is attributed to the flexible ether linkage. The thermal stability of a brominated aromatic polycarbonate (PC-2) is less than that of the unbrominated one (PC-1). The brominated aromatic polycarbonate (PC-2) has good flame retardency, as indicated by the large limiting oxygen index 56.
π SIMILAR VOLUMES
The use of m-ethynylphenol (m-EP) and p-t-butylphenol (PTBP) as coterminators for bisphenol A polycarbonates (BA PCs) provided long-chain-branched PCs, partially crosslinked PCs, or both after the thermal reaction of the terminal m-EP groups, depending on the molar ratio of the chain terminators. Li