Effects of the vulcanizing reagent addition on the properties of CNTs/SBR powder composites

• Published in: Journal of applied polymer science 2007-11, Vol.106 (3), p.1836-1841
• Main Authors: Zhou, Xiangwen, Zhu, Yuefeng, Liang, Ji
• Format: Article
• Language: English
• Subjects: Applied sciences; carbon nanotubes; Composites; Exact sciences and technology; Forms of application and semi-finished materials; mechanical property; Polymer industry, paints, wood; rubber nanocomposites; spray drying; styrene-butadiene rubber latex; Technology of polymers
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.24495

Vulcanizing reagent (VR) suspensions with different sulfur additions were mixed with CNTs suspensions and SBR latex, and then powder CNTs/SBR (PSBR) composites were prepared by spray-drying process. Investigations showed that VR additions have significant influences on the properties of CNTs/PSBR composites. With the increment of VR additions, glass transition temperature (Tg) of the composites increased gradually, and reached the maximum when the sulfur addition was 4.0 phr, and then it would decrease if the sulfur addition continued to rise. The elongation at break of the vulcanizates decreased linearly. The tensile strength and hardness reached the maximum when the sulfur addition was 4.0 phr, and almost kept constant when the addition continued to rise. Yet the tear strength reached the maximum when the addition was of 2.5 phr, and then decreased slightly when the addition exceeded 4.0 phr, which was corresponding to the structure designability of the composites affected by the sulfur aggregates in the matrix. Under different temperatures, when the vulcanizing temperature was 150°C, the vulcanizing speed was proper, vulcanizing time was prolonged, and the vulcanizing security was intensified. Compared with the vulcanization of carbon black/PSBR composites, more sulfur additions are needed in the vulcanization of CNTs/PSBR composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007