【作者】 王洪涛；

【导师】 卢咏来；

【作者基本信息】 北京化工大学 ， 材料加工工程， 2009， 硕士

【摘要】 近年来,聚合物层状硅酸盐纳米复合材料由于其与传统材料和微米或宏观材料相比,具有模量高、强度高、耐热性高、以及气密性好和阻燃等优点,引起了研究者在应用和理论研究方面的热潮。层状硅酸盐片层的分散型态在很大程度上影响着纳米复合材料的各种性能。本论文提出了一种制备橡胶/黏土纳米复合材料(RCN)的新方法:将超细交联丁腈橡胶(UFPNBR)乳液与黏土悬浊液共混,使UFPNBR胶乳粒子与黏土片层彼此穿插隔离;采用喷雾干燥工艺迅速脱水,制备得到无机黏土剥离型分散的UFPNBR/黏土(MMT)共混粉末(UFNBRM)。将UFNBRM与丁腈橡胶(NBR),丁苯橡胶(SBR)和三元乙丙橡胶(EPDM)通过熔体共混制备黏土/超细全硫化粉末橡胶/橡胶三元纳米复合材料。对该纳米复合材料的相态结构,动态力学性能,力学性能和气密性进行了研究,并与OMMT/橡胶共混物做了对比。结果表明:(1)通过扫描电子显微镜(SEM)观察发现UFNBRM混粉末为几微米到几十微米左右的橡胶颗粒,且粒径和表面形态均随黏土含量提高而显著变化。广角X射线衍射(WAXD)和透射电子纤维镜(TEM)研究表明,无机黏土在UFPNBRM中呈剥离型分散。(2)TEM观察表明在MMT/UPFNBR/NBR三元纳米复合材料中,无机黏土分散不均匀,大部分黏土仍然以剥离状态分散于UFPNBR中,少量黏土分散在NBR基体橡胶中。UFPNBRM的加入对复合材料的力学性能,气体阻隔性能等有所提高。但由于纳米黏土分散不均一性,复合材料的力学性能低于有机改性黏土(OMMT)增强NBR纳米复合材料。(3)在MMT/UPFNBR/SBR与MMT/UPFNBR/EPDM三元纳米复合材料中,由于UFPNBR与SBR,EPDM极性差异较大,相容性不好,UFNBRM在基体橡胶中发生了明显的团聚现象,使纳米黏土的增强效应不能充分发挥。由于粘土片层大径厚比,三元纳米复合材料的气体阻隔性能有所提高。更多还原

【Abstract】 Recently layered silicate/polymer nanocomposites have attracted many researchers’ interests because of their high modulus, high strength, high heat resistance, and good air tightness and flame retardant compared to traditional materials. Layered silicate dispersed have effect on various properties. In this work, we prepared a new method of preparation rubber / clay nanocomposites (RCN) : Na-montmorillonite (MMT) powder was dispersed into water to prepare clay slurry. A novel ultra-fine full-vulcanized acrylonitrile butadiene rubber rubber latex(UFPNBR) was added into the clay slurry at a certain dry weight ratio and stirred to form uniform mixture, in which the clay layers and the latex particles were interpenetrated each other. The mixture was then spray-dried to obtain UFPNBR/MMT blends (UFPNBRRM). The morphology of UFPNBFRM was characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM).UFNBRM blend with acrylonitrile-butadiene rubber (NBR), styrene-butadiene rubber (SBR) and ethylene propylene diene monomer (EPDM), Clay/UFPNBR/Rubber nanocomposites were prepared by melt blending so that without modified inorganic clay dispersed in rubber matrix . The morphology, dynamic, static and gas permeability properties of this kind novel rubber blends were investigated and compared with those of modified inorganic clay /rubber blends.The main results are listed as following:(1)SEM observation showed that UFPNBRM powders was a few microns to tens of microns particles, the higher the Clay content, the smaller the particles. WAXRD demonstrated characteristic diffraction peak of clay disappear, analysis showed that the clay of the short-range ordered structure was damaged. TEM observation showed that the clay silicate layers were exfoliated into about 1 nm thick monolayers and randomly dispersed in UFNBR matrix.(2) In the UFPNBRM/NBR composites, TEM observations showed that Clay was mostly dispersed in UFPNBR matrix, a few of them could been find in the NBR matrix, Dynamic property illustrated by DMTA demonstrated that UFPNBR/NBR had good compatibility. UFPNBRM has contribution to the properties of rubber blends, such as mechanical and gas barrier properties. Because of poor dispersion and weak interaction, compared with organic modified clay, there is still some way to go.(3) In the UFPNBRM/SBR and UFPNBRM/EPDM composites, as a result of SBR, EPDM with UFPNBR had polar differences, poor compatibility made clay dispersed difficultly. UFPNBRM/SBR blends did not significantly improve the mechanical properties. Clay good shape factor increased barrier effect to gas, but UFPNBR dispersed in the rubber matrix badly , clear two-phase interface exist in the blends, which made barrier effect decreaseing can not compared with OMMT.更多还原