脲醛树脂/异氰酸酯胶粘剂组合施胶对纤维板性能的影响

Effects of urea formaldehyde resin/isocyanate adhesive combination sizing on the properties of fiberboard

使用三聚氰胺改性脲醛树脂与异氰酸酯胶粘剂组合施胶制备纤维板,研究了不同异氰酸酯添加比例对纤维板物理力学性能、防水性能以及甲醛释放量的影响。研究结果表明:异氰酸酯的引入对纤维板的静曲强度和弹性模量并无显著影响;纤维板的内结合强度随着异氰酸酯用量的增加而逐渐增强,当异氰酸酯用量为脲醛树脂固体含量的20%时,其内结合强度可提高至1.77 MPa,相应的24 h吸水厚度膨胀率可降低至4.6%;异氰酸酯的引入对纤维板的甲醛释放量测试结果并不显著,仅从原来的5.08 mg/(100 g)最低降至4.12 mg/(100 g)。

Fiberboard was prepared with melamine modified urea formaldehyde resin and isocyanate adhesive combination sizing.The effects of different isocyanate addition ratio on the physical and mechanical properties,waterproof properties and formaldehyde emission of fiberboard were studied.The research results showed that the introduction of isocyanate had no significant effect on the static bending strength and elastic modulus of fiberboard.The internal bonding strength of fiberboard increased with the increase of isocyanate content,when the isocyanate content was 20%of the solid content of urea formaldehyde resin,the internal bonding strength could be increased to1.77 MPa,and the corresponding 24 h water absorption thickness expansion could be reduced to 4.6%.The formaldehyde emission of fiberboard was not significantly affected by the introduction of isocyanate,just decreased from 5.08 mg/(100 g)to 4.12 mg/(100 g).