Modern microelectronics devices urgently request low dielectric constant materials with commendable mechanical properties. Novel fluorinated poly(aryl ether)s (FPPEs) were prepared by traditional polycondensation of 4-(4-Hydroxylphenyl)(2H)-phthalazin-1-one (DHPZ), Bisphenol AF (BAF) and Decafluorobiphenyl (DFB) to study bulky phthalazinone effects on mechanical and dielectric behavior of polymers. After the introduction of phthalazinone moieties, FPPEs showed excellent solubility to readily solve in many organic solvents like NMP, DMAc, CHCl₃, and THF. Simultaneously, they exhibited relatively high glass transition temperatures (T_gs) from 180 °C to 294 °C, increasing with the content of phthalazinone groups. The FPPEs still possessed excellent thermal stability with decomposition temperature up to 514 °C and char yield at 800 °C as high as 56% under nitrogen atmosphere. FPPE films showed good mechanical strength with tensile stress higher than 68MPa and modulus surpassing 10.8MPa, also increasing with phthalazinone concentration. The dielectric property of FPPEs was investigated with impedance analyzer. FPPE8020 and FPPE 6040 showed dielectric constant from 3.10-3.30 and dielectric loss of 0.005-0.008 under a large frequency range of 0.02-60GHz. The phthalazinone moieties mainly contributed to the decrease of dielectric constant. The results evidently suggest FPPEs as commendable candidate for those high-tech electronic applications.

The work was aimed at the investigation of influence of peroxide curing system on cross-linking and properties of rubber compounds based on SBR. First, the temperature of vulcanization and the amount of dicumyl peroxide on curing process and physical-mechanical properties were investigated. Then, co-agents Type I and Type II were added to the rubber formulations cured with peroxide. The results revealed that the increase in temperature leads to the acceleration of curing process while both, curing kinetics and physical-mechanical properties were influenced by the amount of peroxide. The application of Type I co-agents resulted in the acceleration of curing process and increase in cross-link density of vulcanizates, which was reflected in the increase of hardness and decrease of elongation at break. The influence of Type II co-agents on curing kinetics was negligible, while most of them caused the reduction in cross-linking degree of vulcanizates. Type I co-agents contributed to the improvement of tensile strength of vulcanizates, while the influence of Type II co-agents on tensile strength was of minor importance.

The copolymerization of CO₂/propylene oxide (PO)/cyclohexene oxide (CHO) was carried out using a Zn-based heterogeneous catalyst, namely a supported multi-component zinc dicarboxylate. The monomer reactivity ratios of PO (r_PO) to CHO (r_CHO) were estimated using the Fineman-Ross and Kelen-Tudos graphical methods. The results showed that the r_PO values were significantly higher than the corresponding r_CHO values in all cases, indicating that the incorporation of CHO into the polymer was kinetically unfavorable. The influence of the reaction temperature and pressure on the monomer reactivity ratios was also discussed. It was found that raising either the reaction temperature or pressure led to an increase in r_CHO. In contrast, r_PO decreased upon increasing the reaction temperature, but exhibited a small fluctuation upon increasing the reaction pressure.

The aging behaviors of PMMA in liquid scintillator at different temperatures of 30 °C, 40 °C, 50 °C and 55 °C under static tensile stress were experimentally investigated with dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC), and the service life of the PMMA was predicted on the basis of the time-temperature superposition approach. The results showed that the higher the aging temperature, the faster the tensile strength of PMMA decreased. Acceleration of aging can be realized by applying high temperatures, and a master curve can be constructed using the time-temperature superposition concept. The linear behavior of the plot of the shift factors versus the inverse aging temperature indicated that the aging mechanism was consistent with Arrhenius's law, and the lifetime of PMMA was predicted to be 25 years at 20 °C.

In this paper, identification system of plastic solid waste (PSW) based on near-infrared (NIR) reflectance spectroscopy in combination with Support Vector Machine (SVM) was presented. A device applied to obtain NIR spectra of plastics in the detection platform was developed. After pre-processing (normalized, 1st derivative and smooth), the repeatability of spectral absorption features was improved, which would assist the identification. A “principal component analysis (PCA)SVM” identification method was proposed to identify polypropylene (PP), polystyrene (PS), polyethylene (PE), poly(methyl methacrylate) (PMMA), acrylonitrile butadiene styrene (ABS) and polyethylene terephthalate (PET) among plastics, and its identification accuracy can reach 97.5%. The type of samples could clearly be identified and the shape of samples could also be roughly discerned. It is clearly shown that this system can achieve good identification results while reducing costs considerably, which has great potential in industrial recycling.

While the stress relaxation is a common phenomenon for polymers, its effect on the stress/strain accelerated aging of the hydrogenated nitrile butadiene rubber (HNBR) cannot be ignored. In this paper, the aging tests of HNBR at various temperature and strain levels were performed. To consider the influence of relaxation behavior during the accelerated aging process under external strains, a modified time-temperature-strain superposition principle considering stress relaxation (TTSSP-R) was proposed. With the general Maxwell model and the constructed master curve of relaxation modulus, the effect of stress relaxation on accelerated aging can be described. It was demonstrated that the proposed TTSSP-R approach provides an accurate evaluation of physical aging of HNBR with the consideration of stress relaxation. It could help the material designer to better understand the long-term performance and reliability of rubber components.