Synthesis And Modification Of Monomer Casting Nylon

In this dissertation, some fundamental problems on monomer casting nylon have been comprehensively studied. Fabrication of MC nylons and modified MC nylons, characterization of their structure and properties, and their polymerization-crystallization and structure-property relationships have been investigated.The MC nylon was synthesized using CH₃ONa as the initiator instead of the traditional NaOH. The results show that the initiator CH₃ONa affects greatly the polymerization rate of caprolactam (CL), and the activator controls the conversion rate of CL. In order to obtain MC nylon with excellent comprehensive properties, the amount of catalysts must be limited within the fixed range. Reduction of the amount of activator is an effective way to increase the impact toughness of MC nylon.Synthetic method of isooctoate rare earth was presented. Mechanical and thermal properties of the MC nylon modified with isooctoate rare-earth have been studied. The results show that the addition of isooctoate rare-earth increases tensile strength, impact toughness, hardness, and thermal stability of the MC nylon.The milled glass fibre was used as stuffing in the MC nylon. The results show that physical and mechanical properties of the MC nylon can be improved effectively by using the milled glass fibre as stuffing in the MC nylon. When the MC nylon is reinforced with 10mass% milled glass fibre, shrinkage of the products is reduced, and heat distortion temperature is 20 ℃ higher. The filler distributes uniformly and the composite products exhibit excellent surface brightness. Tensile strength, flexure strength and compressive strength of the composite are 26%, 13% and 36% higher than the MC nylon, respectively.Effect of the addition of ultrafine talc power on mechanical properties and filler distribution and the toughening agent on toughness of the composite has been studied. The results show that the incorporation of talc power into MC Nylon improves dimensional stability and water absorption property, and increases the heat distortion temperature by 20 ℃. The filler distributes uniformly in the composite and the products exhibit excellent surface brightness. At the same time, the addition of ultrafine talc power can reduce product cost and is suitable to the forming process of the MC nylon. The use of the silane coupling agent improves the compatibility between the filler and the resin, improving mechanical properties of the composites.The use of cenosphere as stuffing in the MC nylon has been investigated. The results...