高邻位羟甲基含量的酚醛胶粘剂制备及其性能研究

通过氢氧化钡和氢氧化钠复合催化、间苯二酚改性的两步甲醛加入法工艺制备了低游离醛、高邻位羟甲基含量的酚醛胶黏剂.采用正交试验设计考察了甲醛与苯酚摩尔比、氢氧化钡用量、氢氧化钠用量和反应时间对制备的酚醛胶黏剂游离醛、游离酚和羟甲基含量的影响,确定了优选制备工艺条件:甲醛与苯酚的摩尔比为1.7∶1,氢氧化钡质量浓度为3.0%、氢氧化钠质量浓度为2.0%、反应时间为2.0h,得到的酚醛胶黏剂游离醛、游离酚含量分别为0.298%、4.192%,羟甲基含量为36.29%.

Preparation of Phenol-Formaldehyde Adhesives for High-Ortho Methylol Group Content and Its Properties

Somephenol-formaldehyde adhesives with the contents of low free formaldehyde and high-ortho methylol group are synthesized with barium hydroxide and sodium hydroxide as the composite catalyst and by adding separately formaldehyde in two times.The effects of the molar ratios of phenol and formaldehyde,the mass concentrations of barium hydroxide and sodium hydroxide,and the reaction time on the contents of free formaldehyde,free phenol and methylol group in the obtained phenol-formaldehyde adhesives are investigated by means of orthogona1 experiment.The results have shown that the optimum conditions of the preparing phenol-formaldehyde adhesives are as follow,the molar ratio of phenol and formaldehyde is 1.7,the mass concentration of barium hydroxide is 3.0%,the mass concentration of sodium hydroxide is 2.0% and the reaction time is 2 h.For the adhesive of the above-mentioned formula,the contents of free formaldehyde and phenol are 0.298% and 4.192% respectively,and the content of the methylol group is 36.29%.