三聚氰胺改性脲醛树脂的合成及其在阻燃胶合板中的应用

用质量分数为18%(基于液体树脂)的三聚氰胺和不同缩聚度脲醛树脂制备了三聚氰胺改性脲醛(MUF)树脂,将聚磷酸铵及其他阻燃助剂与MUF共混后得到阻燃胶黏剂并用于制备阻燃胶合板。结果表明,当尿素与甲醛预先缩聚至水洗数为2.5～7.5时,所制MUF树脂的贮存稳定性良好;在MUF中阻燃剂质量分数小于80%时,胶合板的胶合强度满足国家Ⅱ类胶合板标准,甲醛释放量满足E1级标准;用该阻燃胶黏剂制备的阻燃胶合板,经锥形量热仪燃烧试验,其释热速率和释热总量较普通胶合板有显著下降。分析认为,将MUF树脂与聚磷酸铵阻燃剂共混制得的阻燃胶黏剂,其胶合性能和甲醛释放量满足国家标准要求;用该阻燃胶黏剂对胶合板进行表面处理阻燃性能良好。

Synthesis of melamine modified urea formaldehyde resins and its application

Melamine modified urea formaldehyde(MUF) resins were synthesized using 18 % melamine level(based on liquid resin) and UF base resins that were prepared in advance to various extents.Then it was mixed with ammonium polyphophate and other assistants to prepare fireproof adhesive.The results showed that MUF resins exhibited good storage stability when UF base resin prepolymerized to water miscibility of 2.5-7.5.The shear strengths and formaldehyde emission of plywood,bonded with the adhesive mixed with less than 80 % fire retardants,met type Ⅱ plywood critera and E1 critera,respectively.Cone calorimeter analysis showed that both rate of heat release and total heat release of the plywood treated by fireproof adhesive were significantly lower than those of the untreated plywood.The results indicated that both bond quality and formaldehyde emission of the fireproof adhesive met Chinese national standards,and the fire resistant performance of the plywood coated with fireproof adhesive was excellent.