Viscoelastic, Mechanical, and Glasstomeric Properties of Precision Polyolefins Containing a Phenyl Branch at Every Five Carbons
Viscoelastic, Mechanical, and Glasstomeric Properties of Precision Polyolefins Containing a Phenyl Branch at Every Five Carbons
复制标题
每五个碳原子含有一个苯基支链的精密聚烯烃的粘弹性、机械性能和玻璃体性能
DOI：
10.1021/acs.iecr.7b05395
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发表时间：
2018
影响因子：
4.2
通讯作者：
Justin G. Kennemur
中科院分区：
文献类型：
--
作者：
R. Kieber;William J. Neary;Justin G. Kennemur
研究了精密聚烯烃、聚(4-苯基环戊烯)(P4PCP)及其氢化类似物(H2-P4PCP)的力学和粘弹性性能。两种材料的玻璃化转变温度均为非晶态，玻璃化转变温度为∼17±3°C。流变学研究表明，P4PCP的缠结摩尔质量(Me=10.0kgmol-1)比H2-P4PCP(Me=3.6kgmol-1)大得多，且更接近聚苯乙烯。这两种材料在常温下都具有弹性和形状记忆性能，这一点通过应变滞后测量得到了进一步的探索。单轴拉伸测试表明，H2-P4PCP在最大应变值达500%时的弹性回复率为∼95%。讨论了时间-温度叠加分析、Williams-Landel-Ferry常数和进一步的力学分析，并与以前报道的微观结构中具有类似苯支化含量的乙烯-苯乙烯共聚物进行了比较。
Mechanical and viscoelastic properties of precision polyolefins, poly(4-phenylcyclopentene) (P4PCP) and its hydrogenated analog (H2-P4PCP) containing atactic phenyl branches at exactly every five carbons along the backbone are explored. Both materials are amorphous with a glass transition temperature of ∼17 ± 3 °C. Rheological investigations determined that P4PCP has an entanglement molar mass (Me = 10.0 kg mol–1) much higher and closer to polystyrene than H2-P4PCP (Me = 3.6 kg mol–1). Both materials have elastomeric and shape memory properties at ambient temperatures, which were further explored through strain hysteresis measurements. H2-P4PCP has an elastic recovery of ∼95% at max strain values up to 500% as determined by uniaxial tensile testing. Time–temperature superposition analysis, Williams–Landel–Ferry constants, and further mechanical analysis are discussed and compared to previously reported ethylene–styrene copolymers of similar phenyl-branch content within the microstructure.