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A new method using wet chemistry and instrumental analysis has been developed for evaluating the ring-opening of aziridine tris [1-(2 methyl) aziridinyl] phosphide oxide (MAPO) of the bonding agent used in composite propellant. A reduction was observed in the intensity absorption bands in 1400 and 1040 cmˉ ¹ , characteristic of aziridinic ring. It was also observed, in some cases, that when the number of open aziridinyl ring increases, the NH band in the range 3400-3300 cmˉ ¹ , that appears with ring-opening, is located in the region of lower wave numbers. The study of the synthesis of MAPO derivative indicated side reactions such as homopolymerization of rings and also, with secondary hydroxyl of the 12-hydroxy stearic acid and probable humidity existent in the original sample.

Resumo: Reações para obtenção de derivados de hidantoína foram conduzidas a partir de aldeídos de cadeia curta e da 5,5-dimetilhidantoína. O acompanhamento das reações foi realizado por espectroscopia na região do infravermelho médio (MIR) por meio da formação de novas bandas características da estrutura do composto desejado. A análise MIR revelou que estas alterações espectrométricas ocorrem somente na reação com o formaldeído, indicando a formação do produto 1,3-bis(hidroximetil)-5,5-dimetilhidantoína, em presença de água. As bandas de absorção que confirmam a reação foram observadas em 3334 cm-1 (υ OH), 1770 e 1710 cm-1 (υ C=O) e em 1056 cm-1 (υ C-O), sendo esta última, atribuída ao grupo contendo hidroxila primária. A reação da 5,5-dimetil hidantoína com acetaldeído e com propanaldeído não ocorreu sob as condições adotadas neste trabalho. Abstract: Reactions to obtain hydantoin derivatives were carried out with 5,5-dimethylhydantoin and short-chain aldehydes. Monitoring of the reactions was performed using qualitative mid-infrared spectroscopy (MIR) through the formation of new bands characteristic of the desired product. MIR analysis showed that these spectrometric alterations occur only in the reaction with the formaldehyde, indicating the formation of the desired product, 1,3-bis (hydroxymethyl) 5,5-dimethylhydantoin, in the presence of water. The absorption bands that confirmed the reaction were observed at 3334 cm-1 (υ OH), 1770 and 1710 cm-1 (υ C=O) and 1056 cm-1 (υ C-O), the last of which is assigned to the group containing primary hydroxyl.

In the Brazilian Complete Spacial Mission, the research of Vehicle Satellite Launcher is important. The solid propellant composite used in this vehicle is made with ammonium perchlorate, aluminiun powder and hydroxy terminated polibutadiene resin. In the propellant the bonding agent has a function to promote the interaction between solids and polimeric matrix, improving mechanical properties as stress, strain, aging characteristics and moisture embrittlement. Due its importance in propellant, bonding agent is consider as industrial secret and the literature about it is generic, without greater informations.

The present study shows the synthesis of polyamide 6/6 (nylon 6/6) via interfacial polycondensation of hexamethylenediamine and adipoyl chloride, at room temperature, with the simultaneous impregnation of carbon fibers, using the reaction injection pultrusion (RIP) process. The polyamide 6/6 obtained was characterized by infrared spectroscopy, differential scanning calorimetry, and viscosity measurements. The impregnation of the carbon fibers was evaluated by scanning electron microscopy assisted by electron dispersive spectroscopy showing good carbon fiber/polymer matrix interface. These results show that the combination of the synthesis of polyamide 6/6, at room temperature, with simultaneous impregnation of carbon fiber amplifies the application of this structural thermoplastic composite with different arrangements of the reinforcement.

Poly(epichlorohydrin) was synthesized using anhydrous and hydrate stannic chloride, separately, as initiator. Reactions were conducted in the presence of a diolat 70°C. Polymers were characterized by Fourier Transform Infrared I Spectroscopy (FT-IR), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and hydroxyl value determination. It was observed that water has influence in growing chain, but not in its structural backbone. Besides, the monomer/initiator relationship has a higher influence in overall poly(epichlorohydrin) properties.