Synthesis and characterization of isophorondiamine based epoxy hardeners from aminolysis of PET

Abstract

The solvolysis of poly(ethylene-terephthalate) (PET) is one of the most researched areas in chemical recycling. In this study PET aminolysis with isophorondiamine has been done -in opposition to recent trends -without excess reagent and the raw reaction product was further used without purification. The aminolysis product was thoroughly characterized with nuclear magnetic resonance (NMR) spectroscopy. Isophoronediamine was used as a solvent to prepare amine crosslinker solutions for epoxy resins. The effect of the concentration on the cross-linking reaction and thermomechanical properties were investigated. The curing reaction was found to be significantly accelerated by the presence of the aminolysis product. Both the ethylene-glycol and the terephthal-amide-diamines have a catalytic effect on the reaction. The glass transition temperature decreased with increasing concentrations of the cross-linker solutions due to the decreasing cross-link density. Thus, raw aminolysis products can be utilized for epoxy curing and are advantageous in modifying slower curing cycloaliphatic cross linker systems.

Chemical recycling ofPET: A stepping‐stone toward sustainability

“…The accelerative nature of the EG side product and the terephthalamide diamine main products during the epoxy curing reaction was observed 66 …”

“…59 Fukushima et al carried out organocatalytic aminolysis using The accelerative nature of the EG side product and the terephthalamide diamine main products during the epoxy curing reaction was observed. 66 Meawad and Ibrahim conducted a study to develop a novel bifunctional cement dispersing agent via aminolysis depolymerization of PET waste with 4-amino-1-butanol in the presence of sodium acetate as a catalyst, which contributed to fluidity modification of fresh cement. 67 In this regard, PET waste was subjected to aminolysis using excess EA in the presence of different inexpensive nontoxic catalysts, including sodium acetate, sodium bicarbonate, and sodium sulphate.…”

New Imidazolium Ionic Liquids from Recycled Polyethylene Terephthalate Waste for Curing Epoxy Resins as Organic Coatings of Steel

“…Aminolysis of PET yields diamides or amido amine of terephthalic acid that are produced by several techniques and can be used as curing agents for epoxy resins [22]. PET aminolysis products as epoxy curing agents is still an expanding area that reported few works have been focused to apply as epoxy organic coatings [27,28]. It was previously reported that the aminolysis of PET with cycloaliphatic amines is advantageous in modifying slower curing for epoxy systems [27].…”

“…PET aminolysis products as epoxy curing agents is still an expanding area that reported few works have been focused to apply as epoxy organic coatings [27,28]. It was previously reported that the aminolysis of PET with cycloaliphatic amines is advantageous in modifying slower curing for epoxy systems [27]. In this respect, the present work aims to produce for the first time polyamine amide imidazolium acetate ionic liquid (PAIIL) from aminolysis of PET waste with pentaethylenehexamine (PEHA) to alleviate the environmental pollution from PET waste.…”

One-Pot Depolymerization and Polycondensation of PET Based Random Oligo- and Polyesters

“…Depending on the goal of the solvolysis the reaction parameters can be tailored to produce BHET or oligomers that could be further used in new reactions [5,18,[37][38][39][40][41][42][43]. Usually, oligomers are discarded during the purification processes, only a few studies used these or the raw solvolysis product [44][45][46][47][48]. In most of the cases, the purpose of glycolysis is the reproduction PET via BHET.…”