无机粘土的烷基铵盐改性及NBRCNs的结构与性能研究

Study on alkyl ammonium salts of inorganic modified clay and structure and properties of NBRCNs

采用长链脂肪族季铵盐改性有机粘土的方法,研究了烷基铵盐改性剂的碳链长度及配比对无机粘土(MMT)改性效果的影响。结果表明,同一改性剂配比下,由不同碳链长度的烷基铵盐改性剂改性MMT制备的丁腈橡胶/粘土纳米复合材料(NBRCNs)的微观结构、力学性能和分散相态不同,碳链长度适中的十二烷基三甲基溴化铵(CTAB)改性效果较好,碳链长度较长或较短都不利于MMT的改性。对于碳链长度较短的二十二烷基三甲基溴化铵(DTAB),当DTAB用量增加,粘土片层间距增大,力学性能提高。对于碳链长度较长的十八烷基三甲基溴化铵(STAB),STAB用量降低有助于扩大粘土片层间距和提高力学性能。

In this paper,we studied the effect of carbon chain length and proportion of alkyl ammonium modifier on inorganic clay(MMT).Experimental results showed that,under the same modifier ratio,organic clay was modified by alkyl ammonium of different carbon chain length to prepare NBR/clay nanocomposites(NBRCNs),which possess different microstructures,mechanical properties and dispersed state.The moderate carbon chain length of cetyl trimethyl ammonium bromide(CTAB)makes MMT modification better,the longer or shorter carbon chain length is not conducive to the MMT modification,this may be the molecular chain between the clay layers presence status.For shorter carbon chain length DTAB,organic modifier increased from 4.0g∶1.0g to 2.8g∶1.0g,the lamellar spacing of the clay increased,mechanical properties enhanced.For longer carbon chain length STAB,organic modifier decreased from 2.8g∶1.0g to 4.0g∶1.0g,the lamellar spacing of the clay increased,mechanical properties enhanced.