液化木质素磺酸钙基环保酚醛胶黏剂的合成

Preparation of Liquefied-lignosulfonate-based Phenol-formaldehyde Adhesive with Environmentally—Benign Property

摘要: 探讨了加料方式对传统酚醛树脂(PF)胶黏剂游离酚、醛的影响因素。在此基础上,采用热化学酚化技术活化木质素磺酸钙得到木质素磺酸钙酚化产物,将酚化产物代替苯酚制备低成本的木质素基酚醛胶黏剂(LPF)。实验结果表明,当甲醛分3次加入、碱液分2次加入时,制备的PF胶黏剂具有较低的游离酚、醛,且以苯酚为液化试剂,液化温度 140℃、液化时间 15 min、苯酚与木质素磺酸钙的质量比(酚木比)为2:1,酚化工业木质素磺酸钙,将得到的酚化液代替苯酚在酚醛物质的量之比为1:1.7时,制得的LPF具有更低的游离酚、醛含量、较长的储存期和优异的胶合性能。

Abstract: Phenol-formaldehyde (PF) adhesive of low free PF content and low cost was synthesized. The influences of different type of adding materials, formulation and procedure for liquefaction of lignin on free PF value were discussed respectively by means of single factor experiments. Result indicated that, the optimum processing parameters was:addition of formaldehyde by three times; addition of sodiumhydroxide, by twice; weight ratio of phenol-lignin, 2:1; liquefication temperature 140℃; liquefication time 15 min; molar ratio of phenol (amount of phenol and lignin) -formaldehyde, 1:1.7. The resulted lignosulfonate-based PF(LPF) adhesivehas low contents of free phenol and aldehyde, low cost, good glue strength and long storage time.