Comparison of coupling effectiveness among amino-, chloro-, and mercapto silanes in chloroprene rubber

• Published in: Polymer testing Vol. 38; pp. 64 - 72
• Main Authors: Siriwong, Chomsri, Sae-Oui, Pongdhorn, Sirisinha, Chakrit
• Format: Journal Article
• Language: English
• Published: Kindlington Elsevier Ltd 01.09.2014; Elsevier
• Subjects: Applied sciences; ChloroPrene rubber; Composites; Coupling agents; Dispersions; Exact sciences and technology; Forms of application and semi-finished materials; Joining; Mechanical properties; NMR spectroscopy; Particle size; Polymer industry, paints, wood; Reinforcement; Rubber; Silane; Silanes; Silica; Surface modification; Technology of polymers; Mechanical properties; Reinforcement; Surface modification; ChloroPrene rubber; Silica; Silane; Substituent effect; Viscoelasticity; Strengthening; Particle size; Molecular structure; Crosslink density; Dispersion reinforced material; Vulcanizate; Reaction mechanism; Organic oligosulfide; Diene polymer; Organic silane; Tensile property; Chloroprene polymer; Experimental study; Surface treatment; Coupling agent; Polymer filler interaction; Rheological properties
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/j.polymertesting.2014.07.003

Organoalkoxysilane was grafted onto the surface of precipitated silica (PSi), and the modified PSi was characterized by particle size analysis, DRIFT and 29Si NMR spectroscopy. There were 3 types of organoalkoxysilane used in this work, namely, 3-aminopropyl triethoxysilane (APTES), 3-chloropropyl triethoxysilane (CPTES) and bis (3-triethoxysilylpropyl) tetrasulfide (TESPT). The magnitude of the Payne effect, bound rubber content and mechanical properties of chloroprene rubber (CR) filled with unmodified and silane-modified PSi were investigated. Results reveal that the type of silane coupling agent (SCA) affects not only compound processability, but also mechanical properties of the CR vulcanizates. Among the 3 SCAs, it is evident that APTES and TESPT are capable of reducing the filler-filler interaction more efficiently than CPTES, as evidenced by Payne effect results, leading to superior compound processability. Mechanical properties of the CR vulcanizates filled with APTES-modified and TESPT-modified PSi are also greater than those filled with CPTES-modified PSi. This might be ascribed to the combined effects of enhanced rubber-filler interaction and improved filler dispersion.