废聚酯的醇解改性及应用于PUR热熔胶的研究

Study on Alcoholysis Modification of Waste Polyester and Its Application in PUR Hot Melt Adhesive

以1,2-丙二醇为醇解剂,乙酸锌为催化剂,对废聚酯进行醇解,得到聚酯多元醇。将其与聚丙二醇(PPG2000)及聚己二酸丁二醇酯(PBA2000)混合脱水,再与二苯基甲烷二异氰酸酯(MDI)反应得到湿气固化反应型聚氨酯(PUR)热熔胶。通过衰减全反射法(ATR)、剥离强度测定、凝胶渗透色谱(GPC)等确定醇解试剂、醇解时间、催化剂用量等醇解条件对醇解产物的影响及合成条件对反应型湿固化(PUR)热熔胶性能及湿固化反应的影响。最终得到的产物流动性好,黏结强度较高,固化后具备一定韧性。该合成工艺实现了PUR热熔胶部分聚酯多元醇的替代,降低了其原料成本,也为废聚酯的回收利用提供了一条新的技术路线。

Using 1,2-propylene glycol as the alcoholysis agent and zinc acetate as the catalyst,alcoholysis of waste polyester was carried out to obtain polyester polyol.The obtained polyester polyol was mixed with poly propylene glycol(PPG2000)and poly(1,4-butylene adipate)(PBA2000)for dehydration,which was then reacted with methylenediphenyl diisocyanate(MDI)to give moisture curing reactive polyurethane(PUR)hot melt adhesive.The effects of alcoholysis reagent,alcoholysis time,catalyst dosage and other alcoholysis conditions on the alcoholysis products,and the effects of synthesis conditions on the properties of PUR hot melt adhesives were examined by the attenuated total reflection(ATR),mechanical properties determination,gel permeation chromatography(GPC),and other techniques.The final product has good fluidity,high bonding strength,and certain toughness after curing.The synthesis process realizes the substitution of part of the polyester polyol of PUR hot melt adhesive,reduces the cost of raw materials,and also provides a new technical route for the recycle of waste polyester.