MUF胶黏剂的稀释对降低纤维板施胶量的影响

研究了三聚氰胺改性脲醛树脂(MUF)胶黏剂稀释前后低施胶量纤维板的物理力学性能,结果表明:随着施胶量的降低,纤维板的弹性模量(MOE)、静曲强度(MOR)和内结合强度(IB)有所降低,而吸水厚度膨胀率(TS)则有所上升。加水稀释至1.5倍的MUF胶黏剂可以明显提高施胶量为9%的纤维板的MOE、MOR和IB,降低纤维板的TS,而对甲醛释放量影响不大(E1级),并与12%施胶量的纤维板性能相当。而进一步稀释的MUF胶黏剂将使纤维板出现分层鼓泡等现象。
Physical and mechanical properties of fiberboard with lower melamine-urea-formaldehyde(MUF)adhesive content were investigated before and after adhesive dilution. Decreased adhesive content lowered modulus of elasticity(MOE), modulus of rupture(MOR)and internal bonding strength(IB)of fiberboard, but increased its thickness swelling(TS). For fiberboard with 9% adhesive, the 150% dilution of MUF with water led to significantly increased MOE, MOR and IB, decreased TS and almost unchanged formaldehyde emission(grade E1), making its performances comparable to fiberboard with 12% adhesive. However, stratification and bubbling phenomenon were observed for further dilution of MUF