International Journal of Chemtech Applications Vol. 2; Issue 4; Page 1-12 An Open Access Online Scientific Journal ISSN: 2319-7099. Patel et al 1 Carbon fiber reinforced composites based on novel poly(amide-imide)s and epoxy systems M C Patel * , V M Patel, P M Chatrabhuji, Jasmin Kumbhani and H N Der Chemistry Departmentm, Pramukh Swami Science & H. D. Patel Arts College, Kadi- 382 715. Dist. Mehasana, (Gujarat), INDIA. ABSTRACT Carbon fiber reinforced composites were prepared using PAI-Epoxy resin as a matrix material and carbon fibers as fibrous material. Similarly, glass fiber reinforced composites were prepared by replacing carbon fiber with glass cloth. Both types of composites were characterized for mechanical and electrical properties and chemical resistivity. The poly(amide-imide) was prepared by condensation reaction using an equimolar ratio of an amino terminated oligoimide (DDEBMDDS) with various aliphatic bisesters. The PAIs were characterized by elemental analysis, the number average molecular weight estimation and thermogravimetric analysis. The cure reaction of an epoxy resin with PAI was monitored by differential scanning calorimetric method. Key words Diamino diphenyl ether bismaleimide diamino diphenyl sulphone (DDEBMDDS) oligoimide; Poly(amide-imide)s, PAIs; Thermogravimetric analysis (TGA); Glass fiber reinforced composites (GFRC); Carbon fiber reinforced composites (CFRC). INTRODUCTION Many polymers are perticularly suitable as components of composite materials as they adhere readily to the fibers. Thermosetting resins such as epoxides, polyesters, phenolics, silicones and tri- allyl cyanurates are most widely used for the structural applications. One wide class of composite materials in use is the carbon fiber reinforced composites using epoxy resin as a matrix material 1 . Bismaleimide based polymers are prime candidates as matrix resins for advanced composites 2 . To achieve specific combinations of properties, different types of reactants and reaction routs have been used to synthesize tailored bismaleimide resins 3-7 . The resins based on the Michael addition reaction using higher molar ratios of bismaleimide to diamine have been well documented 6-7 . The curing of the resin is achieved with bismaleimide double bonds. Thermally stable materials are also