Chemical recycle of waste FRP by thermal reaction in plant oil

聚合物的热降解不仅受到聚合物的化学成分的强烈影响，而且还受到化学环境的强烈影响，例如溶剂或催化剂的存在。已经报道了关于回收废塑料的热降解的各种研究。对于典型的缩合聚合物，例如聚酰胺（PA）、聚（对苯二甲酸乙二醇酯）（PET），FRP对于不饱和聚酯（不饱和聚酯和玻璃纤维）和聚碳酸酯（PC），已经报道了糖酵解、氨解和甲醇解可以用于以高产率获得单体或聚合物成分。通过溶解聚合物，然后搅拌，可以容易地控制反应温度，并且可以通过从油中提供氢来还原聚合物。因此，由于高度交联的残留物和挥发性物质的量减少，因此可以高收率地获得降解产物。另外，豆油在高温下，即使在大气压下也具有良好的稳定性。研究了玻璃钢在豆油中的热降解行为。在300 ~ 350℃的温度范围内，在30 min内容易生成初始聚合物的低聚物和低分子量产物。降解反应通过聚合物主链的断裂和FRP与甘油三酯（豆油）之间的酯交换发生。这是受水和脂肪酸的影响，脂肪酸是在高温下从豆油中获得的。与石油碎片反应的降解物可用作合成沥青或沥青添加剂，分离良好的残余玻璃纤维可返回原料中重复使用。

Thermal degradation of polymers is strongly affected not only by chemical constituents of the polymer but also by the chemical environment, such as the existence of solvent or catalysts. Various studies on thermal degradation for recycling waste plastics have been reported. For typical condensation polymers, such as polyamides (PA), poly(ethylene terephthalate) (PET), FRP(unsaturated polyesters and glass fiber) and polycarbonate (PC), it has been reported that glycolysis, aminolysis, and methanolysis can be used to obtain monomers or the polymer ingredients in high yield.The advantages of the degradation in plant oils are : the reaction temperature can be easily controlled by dissolution of the polymer, followed by stirring, and the polymer can be reduced by hydrogen donation from the oils. Therefore, degradation products can be obtained in high yields because there is a decrease in the amount of highly cross-linked residues and volatile materials.It should be noted that bean oils have good stability at high temperatures, even under atmospheric pressure. We studied the thermal degradation of a scrap of FRP in soybean oil for plastic recycling. In this study, the oligomer of the initial polymer and lower molecular weight products were easily produced within 30 min by heating in the range from 300 to 350℃. The degradation reaction occurs by a break in the main-chain of the polymer and an ester-exchange between FRP and a triglyceride (bean oil). This is affected by water and the fatty acid, which is obtained from bean oil at high temperatures. The degradates that react with the oil fragment can be used as synthetic asphalts or asphalt additives and the residual glass fiber separated perfectly can be back to the raw materials for reuse.