C-IL-012-超高分子量聚乙烯复合材料的流变性能和力学性能研究-李惠林

超高分子量聚乙烯复合材料的流变性能和力学性能研究
盖景刚李惠林
高分子材料工程国家重点实验室，四川大学高分子研究所，成都 610065
关键词：聚乙烯聚丙烯聚乙二醇
超高分子量聚乙烯具有许多优良性质，如：耐磨性，韧性等[1,2]。

但由于它极高的熔体粘度，难以用普通的加工设备和技术进行加工成型。

本文分别研究了单组分插层和复合插层蒙脱土对超高分子量聚乙烯（UHMWPE）加工性能和力学性能的影响。

用PEG改性的MMT（PM）和用甲基丙烯酰氧乙基十二烷基二甲基溴化铵（MDAB）和PEG复合插层的MMT（PMM）都能明显改善UHMWPE/PP共混物的加工性（Fig. 1和Fig. 2）。

随复合物中有机蒙脱土的增加，共混物的加工性能改善更明显。

与UHMWPE相比，复合物UHMWPE/PP/PMM的拉伸强度、断裂伸长率和屈服强度明显提高，冲击性能基本保持不变（Table 1）。

5phr的PMM可以使UHMWPE的拉伸强度提高至47.55MPa，相对于纯的UHMWPE提高了22.84％。

本工作得到国家基础研究专项经费资助（2005CB623800）
Table1 The mechanical properties of pure UHMWPE and its composites
Sample Tensile
strength
(MPa)
Elongation
at break (%)
Yield
strength
(MPa)
Izod-notched
impact strength
(kJ/m2)
UHMWPE
UHMWPE/PP(90/10) UHMWPE/PP/PM (90/10/1) UHMWPE/PP/PM (90/10/3) UHMWPE/PP/PM (90/10/5) UHMWPE/PP/MM (90/10/1) UHMWPE/PP/MM (90/10/3) UHMWPE/PP/MM (90/10/5) UHMWPE/PP/PMM (90/10/1) UHMWPE/PP/PMM (90/10/3) UHMWPE/PP/PMM (90/10/5) 38.71
39.16
42.33
44.12
42.85
43.13
44.83
44.08
44.67
46.52
47.55
396.41
431.22
487.99
540.51
502.62
501.11
521.35
517.40
477.98
505.88
546.19
25.85
26.02
26.66
27.21
28.27
27.61
28.13
28.44
27.33
27.39
27.85
No break
No break
112.86
100.91
96.93
No break
No break
102.87
No break
No break
No break
TEM和XRD的研究结果表明，有机改性蒙脱土剥离和分散程度是影响力学性能的主要因素，PMM在聚合物基体中的插层、剥离和分散情况明显比MM（只用MDAB插层的有机MMT）更完善（Fig.3，Fig.4，Fig.5和Fig. 6）。

Fig. 5 Transmission electron micrographs of UHMWPE/PP/MM (90/10/3).
Fig. 6 Transmission electron micrographs of UHMWPE/PP/PMM (90/10/3).
Fig. 7表明PMM可以显著减小UHMEWPE的球晶尺寸，增加球晶数量，球晶间的界面缺陷减少，共混物的力学性能提高。

Fig. 7 Optical micrographs of (a) UHMWPE, (b) UHMWPE/PP (90/10), (c) UHMWPE/PP/PMM (90/10/1), (d) UHMWPE/PP/ PMM (90/10/3).
参考文献
[1] Lemstra, P. J., Kirschbaum, R. Polymer, 1985, 26, 1372.
[2] Barham, P.J., Keller, A.J. Mater Sci 1985, 20, 2281.
Rheological Behaviors and Mechanical Properties of Ultrahigh Molecular Weight Polyethylene Composites
Jinggang Gai, Huilin Li
State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, Sichuan 610065
Abstract: UHMWPE exhibits a number of desirable chemical and mechanical characteristics. Its application, however, is limited due to its poor processability. In this paper, the effects of OMMT on rheological behaviours and mechanical properties of UHMWPE composites have been investigated. The results showed that the presence of PMM in UHMWPE matrix was found able to lead to a significant reduction of melt apparent viscosity and enhancement in tensile strength and elongation at break of UHMWPE.
Key words: polypropylene polyethylene poly(ethylene glycol)。