Tao Liu¹, Huiyin Shi¹, Chen Chen^1,*, Rong Fu^2,*

International Journal of Mental Health Promotion, Vol.26, No.3, pp. 199-209, 2024, DOI:10.32604/ijmhp.2024.046303

Abstract To explore the relationship between social influence, social comparison, clarity of self-concept, and psychological anxiety among young women during their usage of social networking sites, our study selected 338 young women aged 14–34 from the social site platforms of Little Red Book and Weibo for questionnaire surveys. The Passive Social Network Utilization Scale, Social Comparison Scale (SCS), Social Influence Questionnaire, Self-Concept Clarity Scale (SCCS), and Generalized Anxiety Disorder Scale (GAD-7) were employed to measure the subjects. Our results show that the frequency of passive social media use is positively related to the level of psychological anxiety. Social comparison, social influence,… More >

XIAOYAN LIU^a,*, XU CHEN^a, HONGXING ZHANG^b, CHANGJUN ZHANG^a, SHIYUAN YANG^a, GUANGQUAN LI^a

Journal of Polymer Materials, Vol.36, No.2, pp. 121-132, 2019, DOI:10.32381/JPM.2019.36.02.2

Abstract In this work, three in situ impact polypropylene copolymer(IPC) samples were prepared through Ziegler-Natta catalyst only changing the feed composition (ethylene to ethylene and propylene molar ratio, C2/C2+C3) in gas-phase polymerization reactor. Polymer (IPC) were characterical by solvent classification, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), successive self-nucleation and annealing (SSA), nuclear magnetic resonance(13C-NMR) and scanning electron microscopy(SEM). The mechanical properties of IPC samples were tested.The results indicate that with similar ethylene content, the feed composition which determines the content and structure of EPR and EbP component in IPC, further impacts the rubber phase size and distribution in IPC,… More >

RITESH D. BHATT, JIGNESH P. PATEL, P. H. PARSANIA^*

Journal of Polymer Materials, Vol.38, No.1-2, pp. 71-87, 2021, DOI:10.32381/JPM.2021.38.1-2.7

Abstract Glass/Biofibers/Epoxy methacrylate of bisphenol-C (G/BF/EBCMAS) sandwich composites was prepared by compression molding. G/BF/EBCMAS showed good mechanical and good to excellent electrical properties and excellent chemical resistance. Studied properties are compared with EBCMAS and G/EBCMAS. In comparison with G/EBCMAS, G/BF/EBCMAS showed considerable decline of tensile strength (18-63.4%), flexural strength (18.8-38.7%), flexural modulus (12.8-50.7%), Izod impact strength (17.4-43.5%), Barcol hardness (2.1-16.7%) and dielectric strength (23.8-76.8%) except flexural strength of G/BM/EBCMAS. G/WC/EBCMAS (96.7%), G/B/EBCMAS (79.2%), G/GN/EBCMAS (83.3%) and G/RH/EBCMAS (97.9%) showed decline of volume resistivity, whereas other sandwich composites showed 1150-58233% improvement. The decrease in mechanical properties and dielectric strength of G/BF/EBCMAS sandwich… More >

ASIS K. MANDAL¹, DEBABRATA CHAKRABORTY², MAHUYA DAS³, SAMIR K SIDDHANTA^4,*

Journal of Polymer Materials, Vol.38, No.1-2, pp. 21-34, 2021, DOI:10.32381/JPM.2021.38.1-2.3

Abstract Elastomeric chlorosulfonated polyethylene (Hypalon) and thermoplastic polypropylene (PP) based thermoplastic Vulcanizates (TPVs) were prepared in presence of different doses of partial methyl ester of styrene-maleic anhydride copolymer (PMES-MA) as compatibilizer employing dynamic vulcanization technique. The mechanical analysis of the prepared TPVs exhibited significant improvements in stress at 25% modulus, ultimate tensile strength (UTS), and hardness values. FTIR studies revealed that a chemical interaction had taken place between hypalon and compatibilizer during the process of dynamic vulcanization which led to an enhancement of interfacial adhesion between them. The two-phase morphologies were clearly observed by scanning electron microscopic studies. The Tg values… More >

SHOGO TAKASUKA^1,*, TATSUHIRO TAKAHASHI¹

Journal of Polymer Materials, Vol.38, No.1-2, pp. 1-10, 2021, DOI:10.32381/JPM.2021.38.1-2.1

Abstract The effects of compounds containing oxazoline groups and the presence of maleic anhydridegrafted polypropylene (PP-g-MAH) on the spectral, morphological, and tensile properties of polypropylene (PP)/liquid crystalline polymer (LCP) blends were investigated. A wholly aromatic LCP having a low melting point which was copolyester, namely AL-7000 have been used, because thermal decomposition of PP and compatibilizer must be prevented.Compression molding was selected as the molding method because it allows molding with a small amount of sample. The binary blends of PP and LCP showed a degradation of tensile properties compared to pure PP. However, the addition of 2,2'-bis(2-oxazoline) and PP-g-MAH as… More >

GAURAV AGARWAL

Journal of Polymer Materials, Vol.39, No.3-4, pp. 255-267, 2022, DOI:10.32381/JPM.2022.39.3-4.6

Abstract Studies were conducted to observe the effect of fracture toughness and damping response on fabric reinforced epoxy polymer composites. The samples of glass fabric, kevlar fabric and carbon fabric having 15wt%, 25wt%, 35wt%, 45wt% and 55wt % fabric content were prepared and tested following ASTM standards. Fracture toughness, peak load and increase in energy absorption are determined for the fabric-epoxy composites. Effect of temperature on storage modulus, loss modulus and tan delta values for various percentages of fabric epoxy composites are noticed and corresponding damping response behaviour is determined. The results revealed that reduction in strength at higher percentage of… More >

RITESH D. BHATT, JIGNESH P. PATEL, PARSOTAM H. PARSANIA^*

Journal of Polymer Materials, Vol.39, No.3-4, pp. 223-239, 2022, DOI:10.32381/JPM.2022.39.3-4.4

Abstract Compression-molded epoxy methacrylate of bisphenol-C-jute/treated jute-banana/groundnut/ cane sugar/pineapple leaf/rice husk/wheat husk sandwich composites were fabricated under 5 MPa pressure at room temperature for 3 h. Alkali treated jute-natural fiber sandwich composites displayed considerably improved mechanical properties over untreated jute-natural fiber sandwich composites due to surface modification of the jute fibers. Both types of sandwich composites showed high water uptake tendency, excellent hydrolytic stability against acids, alkali, and salt solutions, and also a longer equilibrium time at 30o C. Alkali treated sandwich composites revealed a considerably lower water uptake tendency than untreated sandwich composites. Observed water uptake trend is H₂ SO₄… More >

RITESH D. BHATT, JIGNESH P. PATEL, PARSOTAM H. PARSANIA^*

Journal of Polymer Materials, Vol.39, No.3-4, pp. 205-221, 2022, DOI:10.32381/JPM.2022.39.3-4.3

Abstract Epoxy methacrylate of bisphenol-C-jute/treated jute and their sandwich composites of white coir, brown coir, wild almond, bamboo, betel nut, and palmyra were prepared by a compression molding technique under 5MPa pressure and at room temperature for three h. The neat sample showed almost double tensile strength than its jute composite, while it is comparable for treated jute. The composites revealed substantially improved flexural strength compared to neat. The neat, jute/treated jute and their sandwich composites indicated good impact strength, pretty good Barcol hardness, and fairly good electric strength. The neat sample showed excellent volume resistivity, while jute/treated jute and their… More >

Xiaojie Liang^1,2, Wei An², Yuekun Li², Yajun Wang², Xiaoya Qin², Yanhong Cui¹, Shuchai Su^1,*

Phyton-International Journal of Experimental Botany, Vol.93, No.3, pp. 467-486, 2024, DOI:10.32604/phyton.2024.047628

Abstract

Goji berry (Lycium barbarum L.) is substantially dependent on nitrogen fertilizer application, which can significantly enhance fruit yield and Goji berry industrial development in Ningxia, China. This study aimed to analyze the functions of differential nitrogen application rates including low (N1), medium (N2), and high (N3) levels in soil microbial community structure (bacterial and fungal) at 2 diverse soil depths (0–20, 20–40 cm) through high-throughput sequencing technology by targeting 16S RNA gene and ITS1 & ITS2 regions. All the observed physicochemical parameters exhibited significant improvement (p < 0.05) with increased levels of nitrogen and the highest values for most parameters… More >

XINGMIN XU¹, QINGQING SUN², AIRONG XU², XINBAO GUO²

Journal of Polymer Materials, Vol.39, No.1-2, pp. 167-181, 2022, DOI:10.32381/JPM.2022.39.1-2.11

Abstract Silk fibroin (SF) with renewability, biocompatibility and biodegradability shows potential application in various fields including biomedicine, tissue engineering, and wearable electronic devices. Herein, SF is used to exert effective reinforcement of polyvinyl alcohol (PVA) composite film to further improve its practicability. As such, PVA/SF composite films were prepared for the first time using a facile approach. The films were characterized to investigate possible interaction of PVA with SF. Meanwhile, systematic investigations have also been completed to explore the influences of PVA/SF mass ratio on the mechanical properties (tensile strength, elongation at break), biodegradability and biocompatibility, the morphology, crystallinity, chemical structure… More >