In this effort, Quickstep, a relatively a new technique, have been employed for manufacturing of composite materials. The cure schedule provided by a prepreg manufacturer is usually designed for autoclave or other traditional processing techniques and thermosetting resin systems are formulated for ramp rate curing 2-3 K min 21 . While in case of Quickstep processing, ramp rates of 15 K min 21 can be achieved, thus changing the chemorheology of resin. The cure process of 977-2A carbon/epoxy composites was evaluated for Quickstep processing using differential scanning calorimetry (DSC), dynamic mechanical and thermal analysis, and Fourier transformed infrared and results were compared with cure cycle employed for autoclave curing. Optimum hold time for Quickstep processing at upper curing temperature (180 C) was determined using DSC. The hold time of 120 min at 180 C was found to be suitable for Quickstep cure cycle, producing a panel of similar degree of cure to that achieved through autoclave processing schedule. Final degree of cure was dependent on time spent at upper cure temperature and slightly on initial steps of the cure cycle which was used to control the resin flow, fiber wetting, and void removal. Quickstep processed samples exhibited higher T g and crosslink density and similar molecular network structure to the autoclave cured samples. POLYM. ENG. SCI.,

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The hygrothermal effect on the flexural, interfacial and glass transition behaviors of 977-2A carbon/epoxy composites cured in an autoclave and by using Quickstep were evaluated in the previous paper. This article concerns with the hygrothermal effect on the mode I and mode II delamination resistance of the samples cured in an autoclave and by Quickstep. It was observed that the mean initiation and propagation GC values (i.e. GIC and GIIC) of both autoclave and Quickstep 60 cured specimens were apparently reduced after hygrothermal conditioning; however, the data obtained from both autoclave and Quickstep 60 cured specimens in dry and wet states were not statistically significant. The scanning electron micrograph confirmed the enhancement of matrix ductility; however, no effect of this matrix ductility was observed in the GIC and GIIC data.

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In order to circumvent the contradiction between processability and electrochemical performances, we report a recombination strategy in both unit and segment scales for processable ambipolar electroactive materials starting from parental moieties: classic ambipolar polymer (PEBE) and its soluble analogue (PPBP). On the basis of this strategy, two recombined polymers (PEB-P and PEBE-PBP) are successfully prepared via direct (hetero)­arylation copolymerization. Through systematical characterization of properties, both PEB-P and PEBE-PBP not only possess the solubility fostered by PPBP but also exhibit identical electrochemical and optical properties to PEBE, demonstrating the reliability of this recombination strategy. Moreover, film electrodes of these recombined polymers exhibit desirable pseudocapacitance, acceptable stability, and superior processability to PEBE, making them promising candidates for Type III supercapacitors and other multifunctional energy storage devices.

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