Synthesis, characterization of new carboxylic acid-containing benzoxazine and its cocuring behaviors with bisoxazoline

• Published in: Journal of applied polymer science Vol. 123; no. 2; pp. 922 - 928
• Main Authors: Li, Shengfang, Zou, Tao
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.01.2012; Wiley; Wiley Subscription Services, Inc
• Subjects: 1,3‐PBO; 3-PBO; Applied sciences; benzoxazine; Benzoxazines; Carboxyl group; carboxylic; Chemical properties; Copolymerization; Curing; Differential scanning calorimetry; Exact sciences and technology; Exothermic reactions; Materials science; Polymer industry, paints, wood; Polymers; Properties and testing; Resins; Technology of polymers; thermal properties; Ring opening polymerization; 1,3-PBO; Oxazoline derivatives; benzoxazine; Curing (plastics); Experimental study; Phenolic resin; Thermal stability; Hydrophily; thermal properties; Preparation; Reaction mechanism; Polyacid; Chemical reactivity; Ring opening copolymerization; carboxylic
• ISSN: 0021-8995; 1097-4628; 1097-4628
• DOI: 10.1002/app.34535

A new benzoxazine‐benzoic acid (BBA) was synthesized and the structure was conformed by 1H‐NMR, 13C‐NMR, FTIR, etc. The cure behavior of BBA and cocure behavior of BBA with phenylene bisoxazoline (1,3‐PBO) were investigated by differential scanning calorimetry (DSC). It was found that BBA showed a single curing exothermic peak at about 217°C. However, all BBA/1,3‐PBO systems exhibited two exothermic peak. One may be attributed to the reaction between carboxyl groups of BBA and 1,3‐PBO. And the other was attributed to the ring‐opening polymerization of oxazine rings and the reaction between phenolic hydroxyl groups generated by the ring opening of benzoxazine ring and 1,3‐PBO. The curing temperature of benzoxazine containing carboxyl groups could be lowered by the copolymerization of 1,3‐PBO. Thermogravimetric analysis showed that the incorporation of ester–amide groups had a significant effect on decreasing thermal stability and char yield of the cured resin. SEM results indicated that 1,3‐PBO could toughen BBA benzoxazine resin. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011