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Abstract: One problem of polymer modified bitumens (PMBs) is the poor compatibility between polymer and bitumens. In this paper, the improved properties of bitumen binders containing various kinds of additive including styrene butadiene rubber (SBR), weathered coal (WC) and carbon black (CB) under different concentrations are investigated. To assess the effects of the type and concentration of the additive on classical properties of bitumen binders, the softening points, penetration, penetration index (PI), ductility and Fraass breaking points before and after RTFOT aging are tested. The dynamic mechanical analysis (DMA) of these binders before and after ageing had been characterized by dynamic shear rheometer (DSR) using a combination of temperature and frequency sweeps. With higher polymer concentrations, it produced a highly elastic network which increases the viscosity, complex modulus and elastic response of the PMBs, particularly at high service temperatures. However, ageing of PMBs tended to result in a decrease in the elastic response of the modified bitumens. It also has been confirmed that the morphology observed by optical microscopy and scanning electron microscope (SEM) revealed the compatibility among SBR, WC and bitumen. The storage stability of binder was also improved significantly. [Copyright &y& Elsevier]

Abstract: Microwave irradiation synthesize organic palygorskite has been successfully prepared. FTIR, XDR and morphology analysis indicate that 5min microwave irradiation of palygorskite (PA) is an appropriate time to improve the structure of PA. PA and organic palygorskite (OP) had marked effect on the high-temperature property of increasing softening point at the content of 1% while SBR had significant effect on the low-temperature properties and improvement of aging resistance with SBR content of 3–4% in SBR/PA and SBR/OP modified asphalts. TG analysis shows that an increase in the size between layers is found. OP has the high mass loss temperature than PA in the presence of SBR. The morphology in accordance with TG analysis indicate that compatibility and storage stability are improved with a homogeneous and stable mix of wavelike structure in modified asphalts. [Copyright &y& Elsevier]

• Subjected oriented bamboo fibre mats to saturated steam heat treatment. • Created a bamboo scrimber composite through decomposition and recombination. • Compared material composition and properties according to use of heat treatment. • The heat-treated composite was more suitable for use in outdoor structures. • The heat treatment provides an environmentally friendly manufacturing method. In this study, bamboo scrimber composites (BSCs) were prepared using untreated (BSC-C) and saturated-steam heat-treated (BSC-T) oriented bamboo fiber mats and phenol formaldehyde resin via successive mechanical decomposition and molding recombination processes. The heat treatment of the oriented bamboo fiber mats significantly improved the dimensional stability of the resulting BSCs, but degraded their bending performance. Among them, the modulus of rupture and modulus of elasticity of BSC-C were 196.6 MPa and 18.5 GPa, which were 1.35 and 1.19 times higher than those of BSC-T, respectively. The bending strength indexed values of both BSC-C and BSC-T conformed to the structural bamboo scrimber standard LY/T 3194-2020. The dimensional stability of BSC-T was particularly suitable for use in outdoor flooring applications according to the bamboo scrimber flooring standard GB/T 30364-2013. Consequently, the developed BSCs are promising alternatives to conventional engineered bamboo products for various construction and flooring applications. [ABSTRACT FROM AUTHOR]