双组分聚氨酯-聚脲涂料的制备与性能研究

Study on preparation and properties of two-component polyurethane-polyurea coatings

采用异佛尔酮二异氰酸酯(IPDI)、不同比例的聚醚二醇(N-220)和聚醚三醇(N-330)与固化剂4,4′-亚甲基双(2-氯苯胺)(MOCA)制备双组分聚氨酯-聚脲(PUU)复合涂料。研究了合成预聚体的适宜反应条件、异氰酸酯指数(R值)、软段中两种聚醚多元醇的比例对涂料性能的影响。通过二正丁胺法、红外光谱(FT-IR)、拉伸强度、接触角、差示扫描量热法(DSC)、扫描电镜(SEM)对涂层进行了分析。结果表明:78℃左右体系反应时间最短,得到的涂料体系稳定。预聚体中R值增加,涂膜的断裂强度增大,断裂应变减小,R=4时,涂膜有良好力学性能。当n(聚醚二醇)∶n(聚醚三醇)=1∶1时,聚氨酯涂料的综合性能最好;n(聚醚二醇)∶n(聚醚三醇)=3∶1时接触角最大;玻璃化转变温度逐渐升高。

Two-component polyurethane-polyurea(PUU)composite coatings were synthesized using isophorone diisocyanate(IPDI),different ratios of polyether glycol(N-220)and polyether triol(N-330),and curing agent 4,4′-methylenebis(2-chloroaniline)(MOCA).The effects of suitable reaction conditions for the synthesis of prepolymers,the isocyanate index(R value),and the ratio of two kinds of polyether polyols in the soft section on the properties of the coating were studied.The coatings were analyzed by di-n-butylamine method,Fourier transform infrared spectroscopy(FT-IR),tensile strength,contact angle,differential scanning calorimetry(DSC),and scanning electron microscope(SEM).The results showed that the reaction time of the system was the shortest at about 78℃,and the obtained coating system was stable.With the increase of R value in the prepolymer,the fracture strength of the film increased and the fracture strain decreased.When R was 4,the film had good mechanical properties.When n(polyether glycol)∶n(polyether triol)=1∶1,the comprehensive performance of polyurethane coating was the best.The contact angle was the largest when n(polyether glycol)∶n(polyether triol)was 3∶1,and the glass transition temperature increased gradually.