以漆酚基乳化剂(UE)和聚乙烯醇(PVA)为混合乳化剂制备了水包油(O/W)型生漆乳液(RLE),用RHEOMETER(R/S)对RLE的流变性进行了研究.讨论了UE10浓度(cUE10)、混合乳化剂浓度(cME)、UE的结构对RLE流变性的影响.结果表明,RLE的黏度随着cUE10的增加而增大,用不同cUE10制备的RLE都有剪切变稀的特性,表现出假塑性流体的行为;当cME≤6.7%,RLE表现出假塑性流体的行为,而当cME≥10.0%,RLE则表现出膨胀型流体的特征;用不同UE制备的RLE均表现出假塑性流体的特征,其流变行为符合Herschel-Bulkley模型,随着UE分子中聚氧乙烯链的增长,RLE的黏度增大,RLE粒子间所形成的某种静态空间网状结构强度增强.
The oil in water(O/W) type raw lacquer emulsion(RLE) was prepared by using a mixed emulsifier of urushiol-based emulsifier(UE)/polyvinyl alcohol(PVA).The effects of concentration of urushiol-based emulsifier UE10(c UE10),mixed emulsifier UE10/PVA concentration(c ME) and the structure of UE on the rheology of RLE were investigated.The results showed that the viscosity of RLE increased with increasing c UE10,and RLE exhibited shear-thinning behavior.At low concentration of mixed emulsifier UE10/PVA(c ME ≤8.5%),RLE belonged to pseudoplastic fluids,and shear-thinning character was observed.As c ME was increased to no less than 9.0%,the viscosity of RLE decreased remarkably with the increasing of shear rate,pass through a minimum,then increased slowly with increasing shear rate,and RLE exhibited swell fluids characteristics.The viscosity of RLE increased with increasing the chain length of oxyethyl groups in UE molecules,and the flow curves of RLE prepared by UE with different chain length of oxyethyl groups were well described by the Hershel-Bulkley equation.Network-like structure between RLE particles became stronger with increasing of chain length of oxyethyl groups in UE molecules.