短切碳纤维分散方式及对纤维增强石膏基复合材料力学性能的影响

Dispersity of chopped carbon fiber and its effect on mechanical properties of gypsum-based composite materials

采用H_(2)O_(2)和NaClO对短切碳纤维进行表面氧化处理,并采用PCE、HPMC以及超声对其进行分散处理,制备短切碳纤维增强石膏基复合材料,并对其力学性能进行研究。结果表明:经过氧化处理后,短切碳纤维表面亲水含氧官能团羟基和羰基含量增多,表面粗糙度增大;氧化处理后的短切碳纤维在PCE溶液中分散效果最好;短切碳纤维的加入有效提高石膏硬化体的抗压强度,当掺1%采用PCE分散处理的6 mm短切碳纤维时,石膏硬化体强度最高,较未掺时提高72.4%,这是由于PCE在短切碳纤维表面的吸附性和PCE与石膏颗粒反应形成的空间位阻效应双重作用提高了短切碳纤维在石膏浆体中的分散性,进而提高了短切碳纤维增强石膏基复合材料的抗压强度。

H_(2)O_(2) and NaClO were used for surface oxidation treatment of chopped carbon fiber.Chopped carbon fiber reinforced gypsum-based composite materials were prepared by three dispersion methods of PCE,HPMC and ultrasonic dispersion,and then the mechanical properties were studied.The results show that the surface roughness of the oxidized chopped carbon fiber increased with the increase of the content of hydrophilic oxygen-containing functional groups hydroxyl and carbonyl,and the oxidized chopped carbon fiber had the best dispersion effect in PCE solution.The mechanical strength of gypsum hardened were effectively improved by adding chopped carbon fiber.The strength of gypsum hardened increased maximum by 72.4%with the chopped carbon fiber treated by PCE dispersion,which content was 1%and the length was 6 mm.The dispersion of chopped carbon fiber in gypsum paste was improved by the dual action of adsorption of PCE on the surface of chopped carbon fiber and the steric hindrance effect formed by the reaction of PCE with gypsum particles,and then the mechanical strength of gypsum-based composites materials was improved.