PP/PA共混高聚物在冲击载荷下的热粘弹性力学响应  

Thermoviscoelastic Mechanical Response of PP/PA Blends at High Strain Rates

作　　者：喻炳[1] 施绍裘[1] 

机构地区：[1]宁波大学工学院,浙江宁波315211

出　　处：《宁波大学学报（理工版）》2005年第2期163-169,共7页Journal of Ningbo University：Natural Science and Engineering Edition

基　　金：总装备部基金(51478050103QT1905);国家自然科学基金(10372046).

摘　　要：采用Instron1342液压伺服试验机和改进的SHPB技术对2种不同相容剂和重量比的4种PP/PA共混高聚物进行了应变率在10-4～103s-1宽广范围,温度为25℃、40℃、60℃、80℃下的一维应力力学性能试验.结果表明这类共混高聚物的力学响应对温度和应变率都是敏感的.在准静态时,以PPgMAH作相容剂的PP/PA三元体系的应力幅值要高于用TPEg作界面相容剂的PP/PA三元体系,而在承受冲击载荷下,TPE-g作相容剂的PP/PA三元体系比PPgMAH作相容剂的三元体系更有韧性.而在相容剂相同的条件下,随着相容剂质量比重的增加,使得尼龙粒子分布的更加均匀,虽然降低了一定的强度,但提高了韧性.以113材料为例,由其从10-4～103s-1宽广应变率范围内,20～80℃下的试验数据为依据,以“朱—王—唐”非线性粘弹性本构方程来描述这类PP/PA共混高聚物的力学响应,并拟合得到了其热粘弹性本构参数,理论预言与实验结果在应变小于7%时吻合良好.By using Instron 1342 testing system and an improved SHPB technique, four kinds of PP/PA blends with two types of interface modifier and different weight ratio are tested at a wide range of strain rates from 10~ -4 up to 10~3 s~ -1 and at a temperature range of 25-80 ℃. Their mechanical responses are all shown to be sensitive both to the strain rate and temperature. At quasi-static condition, the stress level at a constant strain of ternary PP/PA blends system with PP-g-MAH interface modifier is higher than that of PP/PA blends with TPE-g interface modifier. But under the impact loading, the latter is more ductile. With the increasing of the weight ratio of the interface modifier,the uniformity of the distribution of polyamide particles in PP matrix is improved. And the toughness of the blends is increased while its strength is decreased slightly. Based on the experimental data of 113 blends at a wide range of strain rates from 10~ -4 up to 10~3 s~ -1 and at a temperature range of 25-80 ℃, it is shown that the mechanical behavior of this type of PP/PA blends can be described with ZWT thermoviscoelastic constitutive equation. The corresponding thermoviscoelastic parameters for 113 blends are obtained. The predicted theoretical results meet quite well with the experimental data.

关 键 词：PP/PA共混高聚物 冲击载荷 热粘弹性本构响应 相容剂 

分 类 号：O39[理学—工程力学] TB12[理学—力学]