Preparation And Properties Of Carbon Nanotube/Solution Styrene Butadiene Rubber

Because of its excellent performance, carbon nanotube is widely used in the preparation of composites, especially in the preparation of rubber composites. As a kind of functional filler, the addition of CNTs can not only improve the mechanical properties of rubber, but also can enhance the thermal conductivity and electrical conductivity of rubber.However, the dispersion of CNTs and the interface between CNTs and rubber matrix are the two major challenges that must be solved in the preparation of CNTs / rubber composites, and the main contents of this paper are as follows:1. Firstly, the CNTs/SSBR masterbatch was prepared by solution mixing method, and then the mechanical mixing was used to mix the SSBR and masterbatch to prepare the CNTs/SSBR composites. The influence of the preparation process of masterbatch on the dispersion of CNTs in the masterbatch and the composite materials were studied, and its influence on the properties of composites also been studied. The experimental results show that the directly mixing of CNTs and SSBR solution was the best preparation process of CNTs / SSBR masterbatch.In addition, CNTs will broken during the machining process when the degree of bending reaches the critical value, so in this part of the study,based on the conclusion of Salinas et al., The critical bending aspect ratio of CNTs after mechanical mixing on two-roll mill was calculated. The results showed that the theoretical critical bending aspect ratio of CNTs was 33.2. Firstly, the CNTs wes modified by the mercapto silane coupling agent to prepare the thiolate CNTs, then the mercaptoated CNTs / SSBR masterbatch was prepared by mixing thiolated CNTs with SSBR solution,besides the masterbatch was treated at a temperature of 140? by a Hucker mixer to make the mercapto group on the CNTs surface reacted with the vinyl group in the styrene-butadiene rubber , and the reaction between the mercapto group and vinyl group is called "Thiol-ene"reaction, the reaction degree of this masterbatch was characterized by FT-IR and NMR.After finished the above work, the thiolated CNTs /SSBR composites was prepared by the mechanical mixing of high temperature treated masterbatch, raw SSBR and other additives. A series of performance tests show that, after modification, the dispersion of CNTs in the composites was better than that of the original CNTs, and the tensile strength, elongation at break of the thiolated CNTs / SSBR composites are slightly better than that of the CNTs / SSBR composites.3. The CNTs were modified by carbon-carbon weakly functionalized styrene-butadiene rubber (SBTR), and the modified CNTs were characterized by FT-IR and TGA. The results of the FT-IR showed that the methylene peak, benzene ring peak of SBTR had existed in the surface of SBTR-CNTs, and the results of the TGA showed that the the graft amount of SBTR was 19%. After modification of CNTs, SBTR-CNTs/SSBR, CNTs/SSBR composites were prepared by using SSBR as matrix and the SBTR-CNTs, CNTs as fillers. The effect of SBTR on the composites properties was investigated by a series of performance analyzes. The results showed that the tensile strength, modulus and thermal conductivity of SBTR-CNTs/SSBR composites were higher than that of CNTs/SSBR composites. The main reason was that the interface effect of SBTR-CNTs/SSBR composites is higher than that of CNTs/SSBR composites.