Effect of CO2 fixation reaction on the thermal and dynamic mechanical properties of tetrafunctional epoxy resin

Abstract

A tetrafunctional epoxy resin was modified using CO 2 fixation process in the presence of tetra-n-butyl ammonium bromide as catalyst. The unmodified tetrafunctional epoxy resin (UMTE) and CO 2 fixated modified tetrafunctional epoxy resin (CFMTE) were cured by diethylenetriamine. A bifunctional glycidyl ether compound was used as a reactive diluent to control the viscosity of CFMTE. The activation energy of curing reaction was computed using the advanced integral isoconversional method. The activation energy, which depends on the conversion, was considerably changed due to the CO 2 fixation process. The thermal stability parameters including the initial degradation temperature, the temperature at the maximum rate of weight loss (T max ), and the decomposition activation energy (E d ) were determined by thermal gravimetry. Dynamic mechanical thermal analysis measurements showed that the CO 2 fixation decreases the T g of the epoxy resin. The surface morphology of UMTE and CFMTE were determined by scanning electron microscope. It is concluded that CO 2 fixation reaction improves the properties of tetrafunctional epoxy resin.

CO2-fixation into cyclic and polymeric carbonates: principles and applications

“…9D) was modified by converting a fraction of the epoxide moieties into cyclic carbonate groups (18 and 48%). 318 Similarly to the above-mentioned bifunctional epoxy resins, 322,324,325 higher curing rates with diethylenetriamine were observed for the tetrafunctional CO 2 -modified epoxy resins. The thermal properties were also affected by the CO 2 -modification ( Table 10, entries 7 and 8): the observed lower T g of the final crosslinked network and the slight decrease in initial decomposition temperature were ascribed to the decrease in crosslink density.…”

“…coatings, adhesives, foams, laminates, composites and electronic materials. 318,319 Their extensive utilisation is a result of their excellent properties upon curing (i.e. upon crosslinking of the resin into a higher molar mass polymeric network), 320 including high tensile strength and Young's modulus, high thermal stability, broad solvent resistance, high adhesion strength, heat resistance and high electrical resistance.…”

“…This higher number of epoxide groups per molecule leads to cured resins with higher crosslink density, better chemical resistance, higher thermal stability and better cohesiveness compared to cured resins originating from linear bifunctional epoxides. 318 Although this could yield products with similar crosslinking densities as compared to traditional ones obtained through multifunctional amines, the resulting thermal and mechanical behaviour could be different (different chemical structure at and between the crosslinking points). In this respect, these synthetic routes offer a relevant strategic flexibility.…”

Linseed oil‐based reactive diluents preparation to improve tetra‐functional epoxy resin properties

“…Many remarkable diverse properties of epoxy resins, such as low cure shrinkage, compatibility with a great number of materials, strength, adhesion, and many other notable properties, make this resin prominent as a high‐performance resin for numerous industrial utilizations such as adhesion, coatings, and polymer composites . Among epoxy resins, 4,4‐tetradiglycidyl diaminodiphenyl methane (TGDDM) is the one used for advanced polymeric composites mainly due to its high oxirane functionality.…”

Responses of Chemical Functional Groups in Coleus Blumei Roots under Lead Stress with Exogenous Selenium Treatment Using 2-dimensional Correlation FTIR Spectra

“…The absorption peaks displacement of certain functional groups involved in heavy metal adsorption changes to different degrees, e.g., the absorption peak of OH group (3,416-3,900 cm −1 ), and carbonyl group (1,000-1,100 cm −1 , and 1,270 cm −1 ), which may act as Pb ligands and participate in the processes of Pb sequestration in coleus roots with exogenous Se treatments [38]. In addition, a new peak appeared at 2,130-2,353 cm −1 (C=O stretching of CO 2 ) under Pb stress with different concentration of Se treatments, except for Pb1.0Se0.5, which demonstrates the existence of transition-metal complexes affecting intercellular CO 2 [39]. Semi-quantitative data are used to compare spectral data from samples in order to obtain information on how different functional groups respond differently to environmental changes [40][41].…”