Preparation and Properties of Acetoacetic Ester-Terminated Polyether Pre-Synthesis Modified Phenolic Foam.

Tiejun Ge,Kaihong Tang,Xiaojun Tang

doi:10.3390/ma12030334

Abstract

In the present study, acetoacetic ester-terminated polyether was selected as a modifier to prepare a new type of polyether phenolic resin, which was successfully prepared by pre-synthesis modification. It is used to prepare interpenetrating cross-linked network structure modified phenolic foam with excellent mechanical properties. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (1H NMR, 13C NMR) were used to characterize the molecular structure of the polyether phenolic resin. The results showed that the acetoacetic ester-terminated polyether successfully modified the phenolic resin and introduced a polyether skeleton into the resin structure. The effect of changing the added amount of acetoacetic ester-terminated polyether from 10% to 20% of the phenol content on the mechanical properties and microstructure of the modified phenolic foam was investigated. The results showed that when the amount of acetoacetic ester-terminated polyether was 16% the amount of phenol, this resulted in the best toughness of the modified foam, which had a bending deflection that could be increased to more than three times that of the base phenolic foam. The modified phenolic foam cell diameter was reduced by 36.3%, and the distribution was more uniform, which formed a denser network structure than that of the base phenolic foam. The bending strength was increased by 0.85 MPa, and the pulverization rate was as low as 1.3%.

Highlights

With the rapid development of the construction industry, phenolic foam is widely used in building materials for its excellent flame retardancy [1]
The results showed that when the amount of acetoacetic ester-terminated polyether was 16% the amount of phenol, this resulted in the best toughness of the modified foam, which had a bending deflection that could be increased to more than three times that of the base phenolic foam
The modified phenolic foam cell diameter was reduced by 36.3%, and the distribution was more uniform, which formed a denser network structure than that of the base phenolic foam

Summary

Introduction

With the rapid development of the construction industry, phenolic foam is widely used in building materials for its excellent flame retardancy [1]. This situation has greatly promoted the improvement of the production process of phenolic foam. The benzene ring in the molecular structure is only connected by a methylene group, and the resin forms a uniform and stable three-dimensional network structure. This structure causes the density of the rigid group (benzene ring) to be large. The packing is tight, the steric hindrance is large, and the degree of freedom of the link rotation is small, resulting in the low elongation and high brittleness of the pure phenolic foam [3,4]

Methods

Results

Conclusion