丙烯酸接枝共聚改性水性硝化纤维乳液的合成及性能研究

Study on synthesis and properties of waterborne nitrocellulose emulsion modified by acrylic grafting copolymerization

将丙烯酸(AA)与丙烯酸羟乙酯(HEMA)共聚产物引入硝化纤维分子上,采用自乳化法,合成了一种新型水性硝化纤维(NC)乳液,研究了HEMA、异佛尔酮二异氰酸酯(IPDI)和引发剂偶氮二异丁腈(AIBN)的用量对乳液以及涂膜性能的影响,通过傅里叶变换红外光谱分析(FT-IR)、热重分析(TGA)、粒径分布测量、接触角检测及膜的力学性能测试等方法对所得乳液和涂膜性能进行了表征。结果表明,当AA为5.5 g、HEMA 2.1 g、IPDI 0.65 g、NC 3.6 g、三乙胺6.0 g、AIBN 0.052 g时,所合成的丙烯酸接枝共聚水性硝化纤维乳液呈浅黄色,粒径62.2 nm,能自然稳定存放90 d,所得涂膜吸水率为10.8%,水接触角95.26°,拉伸强度10.8 MPa,其热稳定性高于未改性硝化纤维。

A novel waterborne nitrocellulose （NC） emulsion was synthesized by self-emulsification via introducing the copolymerization product of acrylic acid （AA） and hydroxyethyl acrylate （HEMA） to nitrocellulose molecule. The effects of the dosages of AA, HEMA, isophorone diisocyanate （IDPI）, and initiator azobisisobutyronitrile （AIBN） on properties of the emulsion and its film were studied. The performances of the emulsion and its film were characterized by Fourier transform infrared （FT-IR） spectroscopy, thermogravimetric analysis （TGA）, particle size distribution measurement, contact angle detection, and mechanical property test. The results indicated that the acrylic copolymer-grafted waterborne nitrocellulose emulsion synthesized with AA 5.5 g, HEMA 2.1 g, IPDI 0.65 g, NC 3.6 g, trimethylamine 6.0 g, and AIBN 0.052 g is canary yellow with a particle size of 62.2 nm and stable during the storage at natural state for 90 days. Its film has a water absorption of 10.8%, water contact angle 95.26°, tensile strength 10.8 MPa, and higher thermal stability than the unmodified nitrocellulose film.