南昌航空大学
硕士学位论文
姓名：李璐
申请学位级别：硕士
专业：环境科学
指导教师：熊联明
20080501
摘要
本文研究了三元乙丙橡胶（EPDM）和氯化聚乙烯（CPE）并用胶料的配方设计和应用性能，包括EPDM/CPE并用比、硫化体系、补强体系、软化剂、防老剂，硫化时间等对EPDM/CPE共混硫化胶的物理机械性能、耐热空气老化性能、永久变形等性能的影响，利用电子扫描电镜 (SEM)观察了共混硫化胶 的拉伸断面形貌，分析了其内部共混胶料的相态结构。
研究表明，在EPDM中并用一定量的CPE，有助于改善EPDM的物理机械性能、耐热空气老化性能和扯断永久变形性能。经力学性能测试和SEM观察分析，当EPDM/CPE=70/30时，共混胶料相态均匀，硫化胶的综合性能最好。
在所研究的补强体系中，选择快压出炭黑N550，其粒子表面比较光滑，结构性高，对EPDM/CPE共混胶的补强效果好。但过量的炭黑容易形成聚集体，降低共混胶的力学性能。在本研究中，适宜用量为50份。
随硫化时间的增加，过氧化物硫化胶的硬度和拉伸强度增加，扯断伸长率和永久变形下降。复合交联硫化胶的硬度增大，拉伸强度先增大后降低，永久变形降低。当EPDM/CPE共混胶在压力10MPa，温度150℃的条件下硫化10min时，其硫化胶的综合性能最好。 在所研究的防老剂中，RD与MB并用时，耐热防护效果显著。在RD用量为2.0份，MB用量为1.0份时，对EPDM/CPE共混胶的防护效果较好。
在所研究的软化剂中，石蜡油与DBP并用时，软化和增塑效果明显，同时由于DBP与EPDM的相容性不是很好，有轻微喷出的特点，可提高胶管的脱模性和外观光亮度。但DBP用量不宜过多，研究表明在石蜡油/DBP=5/3时，软化效果最佳。
在过氧化物硫化体系中，采用DCP做为硫化剂，同时加入助硫化剂TAIC，能够明显提高胶料的物理机械性能，改善耐热空气老化性能。当DCP用量为4.0份，TAIC用量为1.0份时，对EPDM/CPE共混胶的硫化效果最好。
防老剂rd利用正交设计助手软件设计正交实验，根据实验结果得到过氧化物硫化体系
各参数的最佳组合为A
3B
3
C
1
D
1
，即：EPDM/CPE= 70/30；DCP用量为4phr； N550用
量为50phr；硫化时间为10min。由此确定出采用过氧化物硫化的最佳胶料配方为：EPDM/CPE 70/30， DCP 4.0, N550 50, TAIC 1.0, RD 2.0, MB 1.0, CTP 0.3, ZnO 3.0, MgO 5.0, 硬脂酸 1.0, 古马隆树脂 2.0, 石蜡油5.0, DBP 3.0。硫化条件为：压力10MPa，温度150℃，时间10min。
最佳配方的过氧化物硫化胶和复合硫化胶的物理机械性都优于纯EPDM。与过氧化物硫化胶相比，复合交联硫化胶的拉伸强度和扯断伸长率更高，但扯断永久变形也更大，且耐热空气老化性能较差。两种硫化胶在力学性能和耐热空气老化
性能上各有所长。对此，可通过对EPDM/CPE采用新的合理的配方设计和加工工艺，实现EPDM/CPE的复合交联，更好地解决硫化胶的力学性能与耐老化性能之间的矛盾，进一步改善EPDM/CPE硫化胶的综合性能，本文对此进行了初步探讨，尚有待于开展进一步的研究。
关键词: EPDM/CPE并用胶；共混；力学性能；耐热空气老化性能；永久变形
ABSTRACT
This thesis studied the formulation design and applied properties of EPDM/CPE blends.How the factors, which are ratio of EPDM/CPE, curing system,reinforcing agent system, softening agent system,and antiagers,affect the physical and mechanical propterties , heat-aging resistance and per
manent deformation of the vulcanizates,was investigated. Furthermore, the fracture surfaces of EPDM/CPE blends were explored and its inner structure was analysed by SEM.
The results showed that the EPDM/CPE vulcanizates have better physical and mechanical propterties , heat-aging resistance and permanent deformation properties. The best blend ratio is 70/30.
Among the studied reinforcing agents, N550 has smooth surface and good structure,so can enhance the strength of blends efficiently. Considering the comprehensive properties of EPDM/CPE vulcanizates,we determine 50 phr as appropriate carbon black dosage.
With the increasing of curing time, the hardness and tensile strength of peroxide-vulcanized EPDM/CPE blends increased,and of which the break elongation and permanent deformation reduced .Meanwhile,the hardness of composite curing EPDM/CPE blends increased, the tensile strength increased at first and then reduced,and the permanent deformation reduced .When the pressure is 10MP,the temperature is 150℃,the curing time is 10min, the comprehensive properties of EPDM/CPE blends are the best.
Among the studied antiagers，RD can protect the vulcanizates rather well. The protective effect und
er high temperature can be improved significantly with addition of MB. When the dosage of RD is 2.0 phr and that of MB is 1.0 phr, the protective effect is better.
Among the studied softeners, nephthenic oil can improve the synthetical performance of EPDM/CPE blends,and it will be better with addition of DBP.But the compatibility of DBP and EPDM is not better.A litter of DBP will spatter out, which can improve the demould property and surface brightness of rubber hose.But the dosage of DBP can not be too much, the better ratio of nephthenic oil and DBP is 5/3.
The physical and mechanical propterties and heat-aging resistance of EPDM/CPE blends will be impoved significantly,using dicumyl peroxide DCP in the peroxide curing system. TAIC can help to initiate free radical , increase the efficiency of
cross-linking,and enhance the properties of heat-aging resistance.When the dosage of DCP is 4.0 phr and TAIC is 1.0 phr, the comprehensive properties of EPDM/CPE blends are the best.
Using the software of orthogonaie design assistant,we achieved the best combination of A3B3C1D1 of the peroxide cure system，that is ,the blend ratio of EPDM/CPE is 70/30；the dosage of DCP is 4phr；the level of N550 is 50phr；the curing time is 10min.Therefore，the best formula is as follows：
EPDM/CPE 70/30，DCP 4.0, N550 50, TAIC 1.0, RD 2.0, MB 1.0, CTP 0.3, ZnO 3.0, MgO 5.0, Stearic Acid 1.0, Coumarone Resin 2.0,Nephthenic Oil 5.0, DBP 3.0.The curing conditions are：Pressure 10MPa，Temperature 150℃，Curing Time 10min.
The physical and mechanical propterties of peroxide-vulcanized EPDM/CPE blends with the best formula and composite curing EPDM/CPE blends are better than that of pure EPDM. Compared with it,the composite curing EPDM/CPE blends have better tensile strength and break elongation but poor heat-aging resistance and permanent deformation.Each of two curing systems has its own advantages.So by optimizing the formula and processing technology of EPDM/CPE,the composite curing system should be improved, which can solve the contradiction between mechanical properties and heat-aging resistance,and the comprehensive properties of EPDM/CPE will be better.For this, this thesis discussed it preliminarily ,and it should be further investigated.
Keywords :EPDM/CPE； blends； mechanical properties；heat- aging resistance；
permanent deformation
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