Evaluation of bisphenol‐A epoxy cured with diethylenetriamine by using phosphorus containing liquid poly(1,2‐butadiene) as multifunctional additives

• Published in: Journal of applied polymer science Vol. 139; no. 48
• Main Authors: Xiaojing, Lv, Wang, Jinwei, Guo, Yong
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 20-12-2022; Wiley Subscription Services, Inc
• Subjects: Additives; Composite materials; Contact angle; Diethylene triamine; Elongation; Epoxidation; Epoxy resins; flame retardance; Fourier transforms; functionalization of polymers; Materials science; mechanical properties; Microspheres; NMR; Nuclear magnetic resonance; phase behavior; Phosphorus; Polybutadiene; Polymers; structure‐property relationships; Water absorption
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.53224

Phosphorus containing liquid epoxidate polybutadiene (P‐LEPB) is synthesized and used as the additive to improve the flame retardancy and toughness of epoxy resin (EP). The structure of P‐LEPB is confirmed by Fourier transform infrared (FTIR), 1H and 13C nuclear magnetic resonance (NMR). With the addition of P‐LEPB, EP composites show earlier degradation; and P‐LEPB plays flame retardancy functions as reflected by the increase of limiting oxygen index (LOI) and its promotion of carbonization as seen from the char scanning electron microscopy images after LOI tests. The addition of P‐LEPB improves the water proof performance of EP composites, playing positive effect on resisting water spreading on the surface and immersing in the EP composites as supported by the water absorption rates and contact angle measurements. The elongation at break increases with addition of P‐LEPB and reaches nearly three times higher than the neat epoxy at P‐LEPB addition of 10%, the toughening effect of P‐LEPB is attributed to the diverting function by the P‐LEPB microspheres upon stress loading, which is related to the size and distribution of P‐LEPB additions as seen from their cross‐sectional images of the composites.