双键封端光固化聚氨酯纸张施胶剂的制备及研究

Preparation and Research of Double-bond Terminated UV-curable Polyurethane Paper Sizing Agent

以4,4'-二环己基甲烷二异氰酸酯(HMDI)、聚己内酯二元醇(PCL)、二羟甲基丙酸(DMPA)、季戊四醇三丙烯酸酯(PETA)、异佛尔酮二胺(IPDA)为主要原料,制得具有确定硬段结构的可光固化水性聚氨酯聚脲乳液,作为特种纸张表面施胶剂.通过傅里叶红外光谱(FT-IR)对其结构进行了分析;系统研究了双键含量(PETA含量)对乳液和涂膜性能的影响:讨论了此类施胶剂对纸张物理性能的影响.结果表明,随着双键含量的增加,乳液粒径增大;光固化后涂膜的拉伸强度增大,吸水率降低,但断裂伸长率降低;光固化后纸张的环压强度、湿强度及平滑度明显改善,水滴接触角增大;而耐折度略有下降.当w(PETA)=8.20%时,耐折度最高,为646次;当w(PETA)=30.88%时,固化后纸张湿强度达到52.3%,纸张平滑度达到85%.通过研究发现,双键封端光固化聚氨酯可显著提高特种纸张应用性能,未来可替代合成聚合物作为特种纸张施胶剂.

A series of waterborne UV curable polyurethane emulision which was a special paper surface sizing agent was pre- pared by self-emulsifying method with hydrogenated MDI （HMDI）, polycaprolactone diols （PCL1000）, 2,2-Dimethylol Propionie Acid （DMPA） , pentaerythritol triacrylate （PETA） and isophorone diamine （IPDA） as raw materials. Fourier transform infrared spectrometer （FT-IR） was used to analyze the structure of emulsion; effects of the content of double bond （PETA content） on the emulsion and film properties were systematically studied. In addition, effects of paper physical properties were discussed. With the increase of content of double bond, the emulsion particle size increases ; the tensile strength of the coating increases after curing light and bibulous rate is lower, but the elongation at break is a little reduced; light cured the ring crush strength of paper, wet strength and smoothness have markedly improved, water contact angle increases; the folding fell slightly.