碱法制浆黑液制备木素酚醛树脂及其应用研究

Study on preparation and application of lignin phenolic resin from alkaline pulping black liquor

在研究纯酚醛树脂合成工艺可行性的基础上,利用碱法制浆黑液替代苯酚合成木素酚醛树脂,对影响其性能的反应回流时间、催化剂用量、黑液添加量进行考察,并应用于刨花板。研究结果表明:碱法制浆黑液可以替代苯酚合成性能良好的木素酚醛树脂,较佳的合成工艺为,反应回流时间60 min、催化剂用量20%、制浆黑液添加量30%。对应的木素酚醛树脂性能指标pH=11.24,动力黏度1560 mPa·s(30℃),固含量51.6%,游离甲醛含量0.114%,胶合强度为1.77 MPa,均符合国标的要求。压制的刨花板性能指标达到了潮湿状态下重载型刨花板的使用要求。

On the basis of studying the feasibility of synthesis process of pure phenolic resin,lignin phenolic resin was synthesized by using alkaline pulping black liquor to replace phenol.The effects of reaction reflux time,amount of catalyst and black liquor addition on its performance were investigated and applied to particleboard.The research results showed that alkaline pulping black liquor could replace phenol to synthesize lignin phenolic resin with good performance.The optimal synthesis process was as follows:reaction reflux time 60 min,catalyst dosage 20%,and pulping black liquor addition 30%.The corresponding performance index of lignin phenolic resin was pH=11.24,dynamic viscosity was 1560 mPa·s(30℃),solid content was 51.6%,free formaldehyde content was 0.114%,and bonding strength was 1.77 MPa,and all of them met the requirements of national standard.The performance index of the pressed particleboard could meet the requirements of heavy-duty particleboard in wet condition.