Preparation of waterborne P-N containing epoxy resin curing and its performances

Abstract

Purpose The flammability of epoxy resin is a major disadvantage in applications that require flame resistance. Epoxy monomers and hardeners containing flame-retardant elements are molecularly incorporated in the resin network are expected to exhibit better flame resistance than those borne on an additive approach. In recent years, because of health and environmental regulation, the use of waterborne coatings has received many attentions. However, waterborne epoxy resin curing agent with excellent flame retardancy has been seldom reported. The paper aims to study the preparation of waterborne P-N-containing epoxy resin curing agent and its performances (P-N – phosphorous and nitrogen). Design/methodology/approach Waterborne P-N-containing epoxy curing agent was prepared in this study using reactive flame retardant 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-xa-10-phosphaphenanthrene-10-oxide, liquid epoxy resin, triethylenetetramine and butyl glycidyl ether at the mole ratio of 1.0:2.0:2.0:2.0. Findings The results show that the epoxy thermoset from the prepared P-N-containing curing agent presents good flame retardancy and can pass the V-1 rating, and the cured epoxy thermoset film presents excellent performances such as water resistance, adhesion, impact resistance and pencil hardness. This study provides useful suggestions for the application of the water-borne flame retardancy epoxy resins in coating industry. Research limitations/implications Each step of products during the preparation of waterborne P-N-containing epoxy curing agent cannot be accurately tested. Originality/value This method for synthesis of waterborne P-N-containing epoxy curing agent is novel and could be used for various applications in epoxy coating industry.

Categories and Application Fields and Manufacturing Process and Action Mechanism of Water Retaining Agent

“…When the amount of acrylamide is small, the amount of -CONH 2 in the system is small, and the synergistic effect with -COONa increases the water absorption and salt resistance of the resin. When the amount of acrylamide is greater than a certain value, with the increase of acrylamide concentration, there are more and more -CONH 2 in the polymer, and the defect of insufficient hydrophilicity of -CONH 2 is obvious, which is not conducive to the water absorption of the polymer [58].…”

Flame-retardancy, thermal and coating properties of P-containing poly-acrylate resin cured with MF resin

“…Water absorption was determined using the equation; (W bef -W aft )/W bef  100 per cent, where W bef and W aft are the weight of the cured film before and after immersion, respectively. The cured films were immersed in deionized water for 24 h (Li et al, 2016).…”

“…This is because when the resins were combusted in air, the P element in the resin was decomposed and generated the phosphoric acid or polyphosphoric acid which promoted the char yield, and therefore formed a compact char residue structure (Sergei et al, 2005). This compact carbon char structure can resist both mass and heat transfer and act as barriers to segregate the transportation of heat, combustible gas and oxygen, therefore reducing the smoke production, heat release and mass loss (Li et al, 2016). However, from Figures 4 (c) and (f), it can be seen that the interior char residue of the P-N containing resin system showed more porous and loose structure compared to the Pcontaining resin system that still displayed a rather compact structure.…”

Preparation of water-based epoxy resin and its application as an automotive air filter paper binder

“…The system was raised to 70 °C, and 26.0 g (0.2 mol) of BGE was added. The reaction was continued for another 3 h to form product II (Li 2016). The solution was cooled to 50 °C and neutralized by various amounts of acetic acid to obtain a self-emulsified epoxy curing agent with various neutralization degrees.…”