ZHAO JUN^a, LIU AIQIN^a, ZHOU HONG^a, LUO JUN^b,*, AND LIU YUAN^b,*

Journal of Polymer Materials, Vol.37, No.1-2, pp. 29-42, 2020, DOI:10.32381/JPM.2020.37.1-2.3

Abstract Heteroatoms (N, O, and F) and hydrogen groups are important elements for forming the H-bonds. It is well known that a large number of hydrogen groups are formed after curing reaction of epoxy. However, literatures about epoxy resins containing heteroaromatic ring and the H-bonds after cure reaction of the epoxy resins are seldom published. To bridge the gap, a kind of new epoxy monomer containing pyridine ring (EMP) has been synthesized in this work, andit is further cured by 4,4-diaminodiphenyl methane (DDM). The properties of cured EMP/ DDM are evaluated by DSC, DMA, and static contact angle measurement. Moreover, the… More >

ZHIHUI HUANG¹, JIAMIAO CHEN¹, YANPING HUO¹, JINGWEI ZHAO²

Journal of Polymer Materials, Vol.38, No.3-4, pp. 257-269, 2021, DOI:10.32381/JPM.2021.38.3-4.7

Abstract The effect of the ether/keto ratios on the thermal properties, mechanical performances and crystallization behavior of the Poly(aryl ether ketone)s (PAEK) were investigated. A formula was proposed the estimate the melting temperatures of the PAEKs with high accuracy. Glass transition temperatures were affected by the ether/keto ratios and molecular weights, and were related with the brittle-tough transition of the PAEKs. Mechanical performances of tensile, impact, flexural and compressive strength decreased with the increase of ether/keto ratios, while elongation had a trend of increase. The non-isothermal crystallization curves exhibited well linearity when treated with Jeziorny’s model, and two crystallization processes were… More >

Jing Yu¹, Jie Ren², Guangming Shen³, Weixiang Sun², Hui Wang^4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2385-2398, 2023, DOI:10.32604/fdmp.2023.027877

Abstract In this paper, the influence of NaCl freeze-thaw (F-T) cycles and dry-wet (D-W) alternations on the flexural, compressive and bonding strengths of alkali-activated fly ash (FA) and a blast furnace slag powder (BFS) is investigated. The considered NaCl concentration is 3%. The effect of polypropylene fibers on the mechanical strengths is also examined. Scanning electron microscopy (SEM), thermogravimetry (TG) and X-ray diffraction (XRD) are selected to discern the mechanisms underpinning the NaCl-induced erosion. The obtained results indicate that the best results in terms of material resistance are obtained with admixtures containing 60% BFS and 40% FA in terms of mass… More >

M. Khennache^1,*, A. Mahieu¹, M. Ragoubi¹, S. Taibi¹, C. Poilâne², N. Leblanc¹

Journal of Renewable Materials, Vol.7, No.9, pp. 821-838, 2019, DOI:10.32604/jrm.2019.06772

Abstract In France, the use of flax fibers as reinforcement in composite materials is growing exponentially in the automotive sector, thanks to their good physicochemical properties, environmental reasons, health neutrality and due to the European Council Directives on the reuse, recycling and valorization of car components and materials. The aim of our study is to investigate biochemical, physicochemical, and mechanical properties of technical flax fibers to evaluate the impact of transformation processes (scutching, hackling, and homogenization) on final properties of associated composite materials. Different chemical analysis such as Van Soest (biochemical fraction measurement), FTIR (Fourier Transform InfraRed spectroscopy), and XRD (X-ray… More >