Alcoholysis of Waste Polyurethane Rigid Foam and Its Modification with Lignin for Recovery
  • Xiaohua Gu1,*, Shiwei Lyu1, Siwen Liu2
1 College of Materials Science and Engineering, Qiqihar University, Qiqihar, 161006, China
2 Shanghai Crane City Polymer Co., Ltd., Shanghai, 201615, China
* Corresponding Author: Xiaohua Gu. Email: gxh218@163.com
(This article belongs to this Special Issue:Renewable Foam Materials and Composites)
Received 18 December 2020; Accepted 19 January 2021 ; Published online 25 May 2021
Abstract
A bi-component alcoholysis agent containing propylene glycol (PG) and ethanolamine (ETA) was used to catalyst the degradation of the waste polyurethane rigid foam. The oligomer polyols obtained through degradation were used as raw materials to produce recycled polyurethane rigid foam composites with lignin as reinforcing filler. The effect of alcoholysis mass ratio on degradation was investigated by analyzing the viscosity, hydroxyl content and chemical structure of the degradation products. The effect of lignin addition on the properties of regenerated polyurethane rigid foam were investigated by analyzing water absorption rate, compressive strength, porosity, thermal stability, thermal conductivity coefficient, morphology and thermal stability of the recycled polyurethane rigid foam. Results show that different mass ration of PG to ETA significantly affects the degradation of waste polyurethane rigid foam. Besides, only with the addition of appropriate amount of lignin, the regenerated polyurethane rigid foam composites can meet the Chinese national standard “rigid polyurethane foam for building thermal insulation” (GB/T21558-2008). At this point, the composite is with good mechanical and thermal prperties, including high compressive strength, excellent thermal insulation performance, complete cell morphology and good thermal stability.
Keywords
Waste PU rigid foam; degradation; bi-component alcoholysis agent; lignin