砂布用水溶性酚醛树脂的研制与性能研究

Study on synthesis and properties of water-soluble phenol-formaldehyde resin used in emery cloth

以苯酚、甲醛和NaOH为原料,采用两步碱催化合成工艺获得固含量为70%～74%的水溶性酚醛树脂.最佳反应条件是n(苯酚):n(甲醛):n(NaOH)=1:2:0.3,在50～90℃程序升温下反应2.5 h,加入少量氯化铵,自然降温50 min,在0.086～0.09 MPa,43～52℃下脱水25 min.将合成树脂植砂,所得砂布力学性能优异,金属磨削量分别为P60 17.5g,P80 12.5g,P100 11.3g,P120 10.7g,脱砂量分别为0.3g,0.4g,0.4g,0.3g.

A water-soluble phenol-formaldehyde resin with the concentration of 70% ～ 74% was synthesized by two-step synthetic technique of alkaline catalysis with phenol ,formaldehyde and sodium hydroxide as raw material. And its optimum technologic conditions were as follows ：the reaction mixture（ n （PhOH） ： n（CH20） ： n（NaOH） = 1： 2： 0. 3 ） reacts for 2.5 h at 50 ～ 90 ℃, then a small amount of ammonium chloride was added and the reaction mixture loers the temperature for 50 min naturally and dewatered by decompressing on the pressure of 0.086 ～0.090 MPa,43 ～52℃ for 25 min. The synthetic resin was used to make emery cloth. The mechanical properties of the obtained emery cloth were very excellent. Their grinding metal amount was P60 17.5 g,PS0 12.5 g,P100 11.3g,and P120 10.7 g,and their corresponding grinding sand amount was 0.3 g,0.4 g,0.4 g and 0.3 g respectively.