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The surface texture of asphalt pavement has a significant effect on skid resistance performance. However, its contribution to the performance of skid resistance is non‐homogeneous and subjects to local validity. There are also a few deep learning models that take into account the effective contact texture region. This paper proposes a convolutional neural network model based on the effective contact texture region, containing macro‐ and micro‐scale awareness sub‐modules. In this study, the asphalt mixture with varying gradations was designed to accurately obtain the effective contact texture region. Then, the textures were disentangled into macro‐ and micro‐texture scales by applying the fast Fourier transform and fed into the model for training. Finally, the area of effective contact texture region was calculated, and the effective contact ratio parameter was then proposed using the triangulation algorithm. The results showed that the effective contact texture area of pavement varies by the asphalt mixture type. The effective contact ratio parameter exhibited a significant positive correlation (Pearson correlation coefficient is 0.901, R2= 0.8129) with skid resistance performance and was also influenced by key sieve aggregate content from 2.36 to 4.75 mm. The data of effective contact texture region following disentanglement significantly released the model performance (the relative error dropped to 1.81%). The model exhibited improved precision and performance, which can be utilized as an efficient, non‐contact alternative method for skid resistance analysis. [ABSTRACT FROM AUTHOR]

Interpenetrating polymer networks (IPNs) possessing a wide damping temperature range are commonly employed as damping materials that are applied in numerous fields. But IPNs will gradually appear to fatigue microcracks and fracture when long‐term in the energy absorption and dissipation. So, the ability for IPNs to recover from damage is necessary that can considerably prolong their service life. Based on polyurethane elastomer and cross‐linked epoxy, several innovative self‐healing IPNs are designed and prepared in this research. The IPNs containing dynamic disulfide bond exhibit favorable damping and self‐healing properties. In detail, the loss factor of IPN‐80/20 is beyond 0.3 at temperatures between −0.8 and 65.5 °C that covers the operating temperature range at room temperature. What is more, The PU/EP IPNs also have excellent shape memory properties, self‐healing ability, and thermal stability. [ABSTRACT FROM AUTHOR]

In order to improve the deficiency of traditional polyvinyl chloride (PVC) heat stabilizer, triazole‐based zinc‐containing complex (abbreviated as [Zn(ttr)(OAc)]) with good compatibility with PVC and a strong ability to absorb HCl was prepared in this paper, which was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM) and thermogravimetric analysis (TGA). PVC sheets were prepared by mixing PVC with composite heat stabilizer (DAJ) composed of [Zn(ttr)(OAc)] and 1,3‐dimethyl‐6‐aminouracil (DAU). Different kinds and amounts of common auxiliary heat stabilizers were selected and added to the DAJ system to study the effect of thermally stable system on PVC by Congo red test, Discoloration test, Dynamic thermal stability test, SEM, TGA and Transmittance test and the relevant mechanism was explored. The PVC sheets with DAJ blended by 1.2 phr DAU and 0.8 phr [Zn(ttr)(OAc)] showed relatively excellent coloring properties, long‐term thermal stability, and high light transmittance. Compared with dibenzoylmethane (DBM), 0.5 phr sorbitol and 1.5 phr epoxy soybean oil (ESBO)/Antioxidant 168 showed good synergistic effect with DAJ. Due to the polyhydroxy nature of sorbitol, the thermal stability of PVC was significantly improved, and the transmittance of PVC benefited from the similar miscibility of ESBO long chain. This was also confirmed by TGA and SEM of PVC sheet. [ABSTRACT FROM AUTHOR]

Silicon hybrid benzoxazine has good flame retardance, but generally these hybrid polymer' curing temperature is higher than 220°C, limiting its application in the field of electronics. In this study, under Nickel acetylacetonate catalyzed, a new hybrid benzoxazine was synthesized using the copolymerization of polysilazane and allyl containing benzoxazine. Differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR) studied the curing behavior of this hybrid benzoxazine. The results of DSC and FTIR indicated that the curing temperature of this hybrid benzoxazine can decrease from 269 to 182°C, the main reaction with this hybrid benzoxazine is amine‐catalyzed oxazine ring‐ opening and the hydrosilylation reaction. The thermal stability of hybrid benzoxazine after cured was studied by a thermogravimetric analyzer. The results of thermogravimetric experiments demonstrated that this hybrid benzoxazine's char yield can increase from 25.57% to 66.11% (159% increase). The flame retardancy of glass fiber reinforced hybrid benzoxazine was studied by the UL‐94 flame test. The glass fiber reinforced hybrid benzoxazine composite show a V‐0 result in the UL‐94 test. This work provides a new hybrid benzoxazine with low‐curing temperature, ultrahigh char yield, and great flame retardance. [ABSTRACT FROM AUTHOR]

In this article, a redox‐responsive poly(ionic liquid) (redox‐PIL) hydrogel Poly(1‐vinyl‐3‐propionate imidazole phenothiazine sulfonic acid)‐chitosan [Poly(VPI+PTZ‐(CH2)3SO3−)‐CS] was produced by using chitosan (CS) crosslinking with redox‐PIL Poly(1‐vinyl‐3‐propionate imidazole phenothiazine sulfonic acid [Poly(VPI+PTZ‐(CH2)3SO3−)]. The incorporation of redox‐active counter anions 3‐(phenothiazine‐10‐yl) propane 1‐sulfonic acid anions (PTZ‐(CH2)3SO3−) into cationic PIL‐polyimidazole rendered Poly(VPI+PTZ‐(CH2)3SO3−) with electron catalytic ability, ionic conductivity, and electron conductivity. Poly(VPI+PTZ‐(CH2)3SO3−)‐CS combines the properties of hydrogel and redox‐PIL, thus offering intrinsic porous conducting frameworks and promoting the transport of charges, ions, and molecules, leading hydrogel with excellent electrochemical properties. The crosslinking occurrence of Poly(VPI+PTZ‐(CH2)3SO3−) and CS resulting from the synthetic process of hydrogel was verified by differential scanning calorimetry and thermogravimetric analysis. A three‐dimensional polymer network hydrogel with good biocompatibility and permeability was formed after crosslinking. In addition, only 64% weight loss within 600 °C was observed in Poly(VPI+PTZ‐(CH2)3SO3−)‐CS representing its thermally stable performance. When used as an electrochemical sensor, the hydrogel‐modified gold electrode improved the electrocatalytic oxidation of cysteine. Differential pulse voltammetry results indicated that the detection range was from 5 × 10−8 to 5 × 10−3 M and the limit of detection was 6.64 × 10−8 M. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48051. [ABSTRACT FROM AUTHOR]