Influence of constitutional defects on polymorphic behaviour and properties of alternating ethylene-tetrafluoroethylene copolymer
Influence of constitutional defects on polymorphic behaviour and properties of alternating ethylene-tetrafluoroethylene copolymer
复制标题
结构缺陷对乙烯-四氟乙烯交替共聚物多晶型行为及性能的影响
DOI：
10.1016/0032-3861(95)93596-e
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发表时间：
1995
期刊：
影响因子：
4.6
通讯作者：
G. Ajroldi
中科院分区：
文献类型：
--
作者：
C. D'Aniello;C. Rosa;G. Guerra;V. Petraccone;P. Corradini;G. Ajroldi
研究了共聚单体摩尔比从50/50变化和引入单体单元引起的结构缺陷和热历史对乙烯-四氟乙烯(ETFE)共聚物的晶型行为的影响。在低温下，C2F4含量在50-70mol%范围内的共聚物可以得到很好的正交结构，但1.8mol%的全氟丙基全氟乙烯基醚单体的含量已经足以形成所谓的伪六方中间相。在高温下，C2F4摩尔含量从50%增加到80%时，六方结构域的结晶度和关联长度基本保持不变，而低浓度(1-3mol%)的三单体单元(基本上排除在晶相之外)强烈地降低了这两个参数。预计这将是ETFE商用三元聚合物的终极性能得到改善的决定性因素。
The influence of constitutional defects (those resulting from variations of the comonomer molar ratio from 50/50 and those due to the introduction of termonomer units) and thermal history on the polymorphic behaviour of ethylene-tetrafluoroethylene (ETFE) copolymer is investigated. At low temperatures, while well developed orthorhombic structures are obtained for copolymers with a C2F4content in the range 50–70 mol%, a content of the perfluoropropylperfluorovinylether termonomer of 1.8 mol% is already sufficient to favour formation of the so-called pseudo-hexagonal mesophase. At high temperatures, the degree of crystallinity as well as the correlation length of the hexagonal domains remain essentially unaltered by an increase of the C2F4molar content from 50 to 80%, while both are strongly reduced by low concentrations (1–3 mol%) of the termonomer units (substantially excluded from the crystalline phase). This is expected to be a determinant factor for the improved ultimate properties typical of commercial terpolymers of ETFE.