水滑石填充聚氯乙烯材料的制备及其性能研究

【作者】 吕杰斌；

【导师】 张强；

【作者基本信息】 北京化工大学 ， 高分子物理与化学， 2001， 硕士

【摘要】 本文用偶联剂钛酸酯、硅烷分别对合成的水滑石进行了表面改性。在双辊塑炼机上制备了水滑石填充聚氯乙烯(PVC)材料。用透射电镜观察了各种水滑石在PVC树脂中的分散性，结果表明用钛酸酯改性的水滑石在PVC中的分散性最好，硅烷改性水滑石次之，未改性水滑石最差。 分别用高温烘箱实验、刚果红实验及热失重实验对水滑石填充PVC材料的静态热稳定性，首次用Brabender转矩流变仪对其进行了动态热稳定性能进行了研究。结果表明，在PVC中不加其他热稳定剂的情况下，单独加入水滑石几乎没有稳定作用，需要与其他稳定剂共用。用水滑石与有机锡共用可以起到很好的热稳定效果，且随着水滑石含量的增加，体系的热稳定性也逐渐增加，但水滑石含量大于2wt％后热稳定效果提高的幅度并不大。由实验结果可得，1份水滑石与1.5份有机锡共用可以起到有机锡2.5份的热稳定效果，可以在工业生产中降低生产成本。 首次用毛细管流变仪及Brabender转矩流变仪研究了水滑石填充PVC材料的流动加工性能。表明水滑石的加入对物料的流动加工性能有一定的影响，水滑石含量为1～2wt％时物料流动性、加工性能最好，继续增加水滑石的含量物料的加工性能又复下降，从加工角度来考虑，水滑石含量应控制在1～2wt％左右。 用氧指数、UL-94垂直燃烧及烟密度法考察了水滑石对PVC材料的阻燃性能，表明水滑石对PVC具有良好的阻燃效果。烟密度测试结果表明水滑石是PVC良好的抑烟剂，添加20-40phr水滑石，就可使PVC的产烟速率及最大烟密度下降约40％。 考察了填充不同份数水滑石后对PVC材料力学性能的影响，表明用偶联剂表面改性过的水滑石在PVC中用量在0～5份范围内，材料的冲击强度没有明显的降低，当超过5份后，材料的冲击性能下降幅度变大，从PVC材料的力学性能的角度考虑也是用钛酸酯改性的水滑石效果最好。 首次分别用红外光谱和紫外光谱研究了水滑石在PVC树脂中的热稳定机理，结果表明，由于水滑石层板上的正电荷与PVC分子链上的Cl所带负电荷间的静电吸引造成了分子链上的Cl与PVC分子链上H的作用力减弱，这种作用使PvC分子中的氯原子，尤其是不稳定的烯丙基氯、叔氯原子趋于稳定，阻止或减缓脱HCI的反应，起到了稳定的作用。同时由于水滑石层板间具有碱性，可以吸收PVC降解时放出的HCI，抑制了PVC降解生成的HCI对PVC的催化降解作用，从而阻止PVC树脂进一步降解。 关键词:PVC，水滑石，填充改性，热稳定性能，加工性能，阻燃性能，力学性能，热稳定机理夕更多还原

【Abstract】 In this thesis, Poly (vinyl chloride) (PVC) resins filled with different content hydrotalcite, which was surface-treated with titanate and silane, were prepared on two-roll mill. The compatibility of hydrotalcite in PVC resin was investigated by TEM and influences of different hydrotalcite content on static > dynamic thermal stability were studied by methods of Congo red test, thermal gravitation balance(TG) and Barbender torque rheometer. The results show the compatibility and thermal stability of hydrotalcite surface-treated with titanate in poly (vinyl chloride) resin is best compared to silane. The poly (vinyl chloride) resin filled with organic Sn and hydrotalcite possess better static and dynamic thermal stability than it filled with organic Sn singly. The heat stability effect of PVC filled with lphr hydrotalcite and 1.5phr organic Sn was similar to it filled with 2.5phr organic Sn singly. The fluid property of PVC resin filled with hydrotalcite surface-trated with titanate was studied by means of Barbender torque rheometer and capillary rheometer. The results showed in certain range hydrotalcite can reduce the melt viscosity of PVC resin, this is advantageous to the processing of PVC resin and optimum content of hydrotalcite was 1%-2%. According to experiment results, hydrotalcite was also a kind of good flame retardant and smoke suppressant for PVC. Impact and tensile strengths of PVC filled with hydrotalcite were studied. The results showed that in certain filling range the impact strength of PVC resin was almost unchanged. When the content of hydrotalcite was more than 5phr, the impact strength decreased greatly. The heat-stabilizing mechanism of hydrotalcite on PVC resin was studied tentatively by means of IR spectrometry and UV spectrometry. The results showed hydrotalcite could absorb HC1 that had catalysis on degradation of PVC resin, so hydrotalcite could improve heat stability of PVC resin.更多还原