MISCIBILITY IN BLENDS OF COPOLYMERS - SEQUENCE DISTRIBUTION EFFECTS
文献类型：期刊论文
| 作者 | CHAI, ZK; SUN, RN; KARASZ, FE |
| 刊名 | MACROMOLECULES
 |
| 出版日期 | 1992-11-09 |
| 卷号 | 25期号:23页码:6113-6118 |
| ISSN号 | 0024-9297 |
| 英文摘要 | Differential scanning calorimetry was used to study the phase behavior in binary blends of copolymers containing the same monomer units, but differing in composition. Examples are chlorinated poly(vinyl chloride) (CPVC), copolymers of methyl and ethyl methacrylate (MMA-EMA), and chlorinated polyethylene (CPE). We find that in the first two systems miscibility can be described in terms of simple mean-field theory for random copolymer blends. Thus the miscibility-immiscibility boundaries for these systems are represented in an isothermal copolymer-copolymer composition plot by two straight lines parallel to the diagonal. Specifically, it was not necessary to invoke sequence distribution effects to account for the observations. In contrast, the miscibility boundaries in the CPE system display deviations from the first-order mean-field theory; the miscibility-immiscibility boundaries display substantial convexities ("bulges") relative to the diagonal, a finding that has been interpreted previously-and in this contribution-in terms of a sequence distribution effect. A new equation based on a revised assumption for triad interaction parameters has been derived for chi(blend), the net copolymer-copolymer interaction parameter. The new equation gives an improved description of the observed miscibility. When chi(AAA;BBB) (the triad parameter corresponding to homopolymer interactions in this approximation) is known, the remaining eight nonzero triad interaction parameters, including chi(ABA;BAB), can be determined. In this analysis the large miscibility behavior difference between CPVC/CPVC and CPE/CPE blend scan be attributed to the effect of microstructure. Triad interaction parameters chi(ijk;lmn) as here defined represent segmental interactions between j and m segments, in each case flanked by the same or differing segments as indicated by the subscripts. |
| 语种 | 英语 |
| WOS记录号 | WOS:A1992JX89000006 |
| 出版者 | AMER CHEMICAL SOC |
| 源URL | [http://ir.iccas.ac.cn/handle/121111/43787]  |
| 专题 | 中国科学院化学研究所 |
| 作者单位 | 1.UNIV MASSACHUSETTS,DEPT POLYMER SCI & ENGN,AMHERST,MA 01003 2.CHINESE ACAD SCI,INST CHEM,BEIJING,PEOPLES R CHINA |
| 推荐引用方式 GB/T 7714 | CHAI, ZK,SUN, RN,KARASZ, FE. MISCIBILITY IN BLENDS OF COPOLYMERS - SEQUENCE DISTRIBUTION EFFECTS[J]. MACROMOLECULES,1992,25(23):6113-6118. |
| APA | CHAI, ZK,SUN, RN,&KARASZ, FE.(1992).MISCIBILITY IN BLENDS OF COPOLYMERS - SEQUENCE DISTRIBUTION EFFECTS.MACROMOLECULES,25(23),6113-6118. |
| MLA | CHAI, ZK,et al."MISCIBILITY IN BLENDS OF COPOLYMERS - SEQUENCE DISTRIBUTION EFFECTS".MACROMOLECULES 25.23(1992):6113-6118. |
入库方式： OAI收割
来源：化学研究所
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