聚硅氧烷对天然橡胶表面耐溶剂性的影响

Effect of polyorganosiloxane on solvent resistance of NR surface

以聚硅氧烷为改性剂对天然橡胶表面进行耐溶剂改性，测试其改性后胶膜在非极性溶剂环己烷中的耐溶剂性能；研究了聚硅氧烷浸涂层数、粒径及种类对改性胶膜耐溶剂性能的影响；采用接触角测量仪测量了胶膜改性前后的接触角；通过傅立叶红外光谱观察了改性后胶膜分子结构的变化。结果表明：聚硅氧烷乳液在胶膜表面的浸涂层数为2层时即可达到良好的改性效果；聚硅氧烷乳液的粒径越小，越有利于胶膜的耐溶剂改性；以OP-10及DBSA为乳化剂聚合所得的硅乳液的改性效果较同等条件下其它硅乳液的效果要好；此外．改性后胶膜的接触角可达128°，并且改性后胶膜在1090-1020cm^-1和1260cm^-1范围内明显存在Si-O-Si和Si-CH3的振动基团。

The surface modification of natural rubber （NR） was carried out by graft polyorganosiloxane. The effect of polyorganosiloxane on solvent resistance of NR surface is studied. The modified NR is studied by using contact angle measurement and infrared spectral analysis. The results indicate that the modified NR has excellent solvent-resistance as polyorganosiloxane covered 2 layers on the NR surface. The particle size of polyorganosiloxane is smaller, the solvent-resistance of modified NR is better. Polyorganosiloxane which is polymerized by OP-10 and DBSA has better modified effect. Besides, the contact angle of modified NR is 128°. Compare to pure NR, the modified NR has symmetric distortion vibration bond of Si-CH3 and strong chain skeletal vibrations of Si-O-Si at 1260 cm^-1 and 1 090-1 020 cm^-1.