不饱和PVB的制备及其对UV固化水性聚氨酯乳液及性能的影响

通过聚乙烯醇缩丁醛与顺丁烯二酸酐制备出含有不饱和基团的聚乙烯醇缩丁醛中间体(MPVB-M),以异佛尔酮二异氰酸酯(IPDI)、聚己内酯二元醇(PCL,M_n=1 000)、二羟甲基丁酸(DMBA)和不同含量的MPVB-M制备得到了一系列紫外光固化水性聚氨酯乳液(UV-WPBU)。通过傅里叶红外(IR)、原子力显微镜(AFM)、扫描电镜(SEM)、X射线衍射和热失重分析等方法研究了聚合物的构性关系;研究了中间体MPVB-M含量对乳液和膜性能的影响。结果表明:随MPVB-M含量的增加,乳液透明度下降,粒径增大,胶膜的耐水性和热性能改善,拉伸强度先增大后减小;扫描电镜表明随MPVB-M含量的增加,胶膜由韧性断裂转变为脆性断裂。当w(MPVB-M)=8.53wt.%时,乳胶粒粒径为79.95 nm,乳液透明稳定;胶膜拉伸强度最大,达到49.82 MPa;吸水率为3.143%,接触角为101.5°;整体性能最佳。

Synthesis and Properties of unsaturated PVBS Modified SUV curable polyurethane emulision

A unsaturated polyvinyl butyral intermediates (MPVB-M) has been synthesized by the esterification reaction of the Anhydride group inSthe maleic anhydride with hydroxyl groups of polyvinyl butyral. The MPVB-M is employed as functional monomer in UV curable polyurethane emulision (UV-WPBU). The structure of emulsion is analyzed by Fourier transform infrared spectrometer (FT-IR) , Atomic force microscope (AFM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Thermogravimetry (TGA). Simultaneously, effects of content of MPVB-M on properties of the UV-WPBU emulsion and its films were systematically studied. With the increase of MPVB-M content,transparency of the emulsion will get worse, particle size increased; thermal stability and water resistance of films have been improved remarkably. At same time, SEM analysis show that the fracture changes from a ductile fracture to a brittle fracture.When w (MPVB-M) = 8.53 wt.%, the latex particle size was 79.95 nm, the emulsion is transparent and stability; the film tensile strength is maximum, at 49.82 MPa; water absorption rate is 3.143%, the contact angle is 101.5 °.