Study On CSBR(BR)/Attapulgite Composites

Attapulgite (AT) is a kind of fibroid silicate clay which is abundant in China. In this dissertation the effects of AT and bis (3-triethoxysilylpropyl) tetrasulfide (Si69) on the structure and properties of carboxylated styrene butadiene rubber (CSBR) and butadiene rubber (BR) were studied.CSBR/AT composites were prepared on a two-roll mill. AT accelerated the vulcanization process and decreased the activation energy of the composites. The mechanical properties and thermal stability of CSBR/AT composites were improved significantly with addition of AT. The tensile strength of CSBR/AT (100/30) composite was 8.0MPa higher than that of pure CSBR. With increasing the AT content, the modulus at 100% and Shore A hardness of CSBR/AT composites were both increased, and the tear strength of the composites was increased at first, then depressed, reaching the maximum of 36.7 KN/m when AT amount was 10phr. AT was uniformly dispersed and oriented as confirmed by using field emission scanning electron microscope (FE-SEM). The integral procedural decomposition temperature (IPDT) of the composites were much higher than that of pure CSBR.Si69 was in situ added and then the CSBR/AT/Si69 composites were prepared on a two-roll mill. Good dispersion of AT in the composites was achieved after the addition of Si69 as shown by transmission electron microscope (TEM). The mechanical properties of CSBR/AT/Si69 composites were better than that of CSBR/AT composites. Kraus plots and the surface energy analysis showed that the interfacial interaction between AT and CSBR was improved after the addition of Si69. The stress softening effect of CSBR/AT/Si69 was more apparent than that of CSBR or CSBR/AT.AT was added into the CSBR latex directly or though a suspension method, and the effect of AT on the viscosity and rheological behavior of the latex was studied. The viscosity of the latex rose evidently by both ways of AT addition and and then kept steady after a long time. Pseudoplastic index of CSBR latex increased with the increasing AT content.BR/AT/Si69 composites had better mechanical properties when 30phr AT was added and dried at 250℃in advance. The optimal concentration of Si69 in BR/AT/Si69 composites was 0.9phr.