As a significant component of composite solid propellants, the cross-link alkenyl polymers need to cure at high temperatures and the current isocyanate curing systems are highly humidity sensitive. This paper presented a low-temperature curing method for a cross-linked polymer (polybutadiene) with stable wettability by using cycloaddition of the nitrile oxide of tetramethyl-terephthalobisnitrile oxide (TTNO) and the C=C group of liquid polybutadiene (PB). The TTNO was synthesized in four steps from 1,2,4,5-tetramethylbenzene and evaluated as a low-temperature hardener for curing liquid PB. To characterize the reaction ability of TTNO at 25 °C, the cross-linked rubber materials of various contents (8%, 10%, 12%, 14%, 16%) of curing agent TTNO were prepared. The feasibility of the curing method can be proved by the disappearance of the absorption peak of the nitrile oxide group (2300 cm−1) by FT-IR analysis. Contact angle, TG-DTA and tensile-test experiments were conducted to characterize the wettability, thermo-stability and mechanical properties of the obtained cross-linked rubber materials, respectively. The results showed that the curing agent TTNO could cure PB at room temperature. With the growing content of the curing agent TTNO, the tensile strength of the obtained cross-linked rubber material increased by 260% and the contact angle increased from 75.29° to 89.44°. Moreover, the thermo-stability performances of the cross-linked rubber materials have proved to be very stable, even at a temperature of 300 °C, by TGA analysis.
The paper describes the synthesis and properties of a tetra-component phenolic resin as a candidate resin for further investigation in photoresist formulations, and its oligomer was synthesized via addition, condensation, and polycondensation reactions. Characterization was conducted using infrared spectroscopy, nuclear magnetic resonance, and gel permeation chromatography. The tetra-component phenolic resin has a weight-average molecular weight of 6376 g/mol and an average alkali solubility rate of 159 ± 2.16 Å/s. Acid-catalyzed crosslinking of HMMM and phenolic resin were used to simulate the crosslinking process of a novolac negative photoresist induced by photoacid. The results indicate that this tetra-component phenolic resin preliminarily meets the requirements for photoresist film formation and could have the opportunity to be used as a candidate resin for further investigation in photoresist formulations.