以偶氮二甲酰胺(AC发泡剂)、Zn O和Na HCO3复合体系作为发泡剂,采用模压发泡的方法制备高填充粉煤灰聚氯乙烯(PVC)复合发泡板材,确定复合发泡剂的最优配比及其在复合发泡板材中的最佳用量,并对其性能进行了研究。采用发气量测定、热重/差示扫描量热(TG/DSC)分析对AC发泡剂进行了改性研究,选出分解温度满足加工条件的复合发泡剂。添加不同份数的复合发泡剂制备PVC复合发泡板材,用扫描电子显微镜(SEM)分析其断面,测试板材的冲击强度及弯曲强度。实验结果表明,当AC发泡剂、Zn O和Na HCO3的配比为2∶1∶1.5时,最大发气量为213 m L/g,分解温度区间为165~177℃,满足PVC发泡板材加工。当复合发泡剂添加量为6份时,力学性能达到最佳,弯曲强度为17.63 MPa,冲击强度为21.88 k J/m2,达到国家硬质聚氯乙烯低发泡板材的标准;粉煤灰填充量高达61.16%。
Composite foaming agent was prepared from azodicarbonamide (AC foaming agent),ZnO,NaHCO3,and high content fiy ash polyvinyl chloride (PVC) composite foamed plate was produced by mould pressing and foaming. Thus the optimal proportion of composite foaming agent and its optimal content in composite foamed plate are confirmed. The function of the compos-ite foaming agent was also studied. Modification research was conducted on AC foaming agent through determination of gas evolu-tion and analysis of TG/DSC, which resulted in composite foaming agent with decomposition temperature satisfying the processing conditions. Different content of composite foaming agent were added to make PVC composite foaming plate, whose section was ana-lyzed by SEM,and whose function of impact strength and fiexural strength were tested. It turns out as follows Whereas AC : ZnO :NaHCO3=2∶1∶1.5,the maximum volume of liberated gas is 213 mL/g,and with the decomposition temperature range is 165-177℃. The conditions to meet the PVC foaming plate processing. It reaches the best mechanical properties with added the composite foaming agent content of 6 phr,bending strength of 17.63 MPa, impact strength of 21.88 kJ/m2,which has reaches the national standard of PVC low foaming plate. The mass fraction of fiy ash reaches as high as 61.16%.