Phase diagram of poly(4-vinylphenol)-N, N-dimethyloctadecylamine mixture
Phase diagram of poly(4-vinylphenol)-N, N-dimethyloctadecylamine mixture
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聚(4-乙烯基苯酚)-N,N-二甲基十八胺混合物的相图
DOI：
10.1021/ma982002y
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
S. Akiyama
中科院分区：
文献类型：
--
作者：
I. Akiba;S. Akiyama
用X射线衍射和光学显微镜研究了聚（4-乙烯基苯酚）-N，N-二甲基十八胺（PVPh-NDOA）混合物的相图。在低温区域，PVPh-NDOA混合物在PVPh-NDOA聚集体晶体的熔融温度以上呈现介观有序相，如梳状聚合物。随着温度的升高，PVPh-NDOA混合物经历有序-无序相变，这是块状或梳状聚合物的特征相变，并呈现均匀的单相。此外，在更高的温度下，PVPh−NDOA混合物显示出LCST型相变，宏观上分离成两个均匀的相。这些复杂的相行为在PVPh-NDOA混合物中的解释与PVPh的羟苯基基团和NDOA的二甲氨基基团之间的缔合平衡，PVPh和NDOA的十八烷基基团之间的排斥，以及熵贡献随温度的变化。
The phase diagram of poly(4-vinylphenol)−N,N-dimethyloctadecylamine (PVPh−NDOA) mixture is investigated by X-ray diffraction measurements and optical microscopy. In the low-temperature region PVPh−NDOA mixtures take the mesoscopically ordered phase like a comb-shaped polymer above the melting temperature of the crystal of PVPh−NDOA aggregates. With elevating temperature PVPh−NDOA mixtures undergo an order−disorder phase transition that is a characteristic phase transition in block- or comb-shaped polymers and take homogeneous single phase. Furthermore, at higher temperatures PVPh−NDOA mixtures show the LCST-type phase transition and macroscopically separate into two homogeneous phases. These complex phase behavior in the PVPh−NDOA mixture is explained in relation to the balances of association between the hydroxyphenyl group of PVPh and the dimethylamino group of NDOA, repulsion between PVPh and the octadecyl group of NDOA, and the variation of the entropy contribution with varying temperature.