Abuzar Abid Siddiqui¹, Mustafa Turkyilmazoglu^2,3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.3, pp. 2487-2512, 2024, DOI:10.32604/cmes.2024.050525

Abstract The physical problem of the thin film flow of a micropolar fluid over a dynamic and inclined substrate under the influence of gravitational and thermal forces in the presence of nanoparticles is formulated. Five different types of nanoparticle samples are accounted for in this current study, namely gold Au, silver Ag, molybdenum disulfide M_oS₂, aluminum oxide Al₂O₃, and silicon dioxide SiO₂. Blood, a micropolar fluid, serves as the common base fluid. An exact closed-form solution for this problem is derived for the first time in the literature. The results are particularly validated against those for the Newtonian fluid… More >

Xiaochu Luo¹, Xiaobing Qi², Zhao Luo³, Zhonghao Li⁴, Ruiquan Liao¹, Xingkai Zhang^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.6, pp. 1233-1249, 2024, DOI:10.32604/fdmp.2023.045737

Abstract Conventional conductivity methods for measuring the void fraction in gas-liquid multiphase systems are typically affected by accuracy problems due to the presence of fluid flow and salinity. This study presents a novel approach for determining the void fraction based on a reciprocating dynamic conductivity probe used to measure the liquid film thickness under forced annular-flow conditions. The measurement system comprises a cyclone, a conductivity probe, a probe reciprocating device, and a data acquisition and processing system. This method ensures that the flow pattern is adjusted to a forced annular flow, thereby minimizing the influence of More >

Wenqing Xiao^1,#, Lewen Tan^1,2,#, Xunjun Chen^1,*, Qiaoguang Li^1,*, Yunqing Ruan¹

Journal of Renewable Materials, Vol.12, No.3, pp. 569-583, 2024, DOI:10.32604/jrm.2023.046662

Abstract

In this article, a series of high refractive indices (1.50–1.53) thiol phenyl polysiloxane (TPS) were synthesized via hydrolytic sol–gel reaction. The Fourier transform infrared spectra (FT–IR) and nuclear magnetic resonance spectra (NMR) results showed that TPS conformed to the predicted structures. Natural terpene linalool was exploited as photocrosslinker to fabricate UV–curing linalool–polysiloxane hybrid films (LPH) with TPS via photoinitiated thiol–ene reaction. LPH rapidly cured under UV irradiation at the intensity of 80 mW/cm² in 30 s, exhibiting good UV–curing properties. The optical transmittance of LPH in the wavelength of 300–800 nm was over 90%, exhibiting good

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Susi Susi^1,2,*, Makhmudun Ainuri^3,*, Wagiman Wagiman³, Mohammad Affan Fajar Falah³

Journal of Renewable Materials, Vol.12, No.3, pp. 513-537, 2024, DOI:10.32604/jrm.2024.045586

Abstract Microcrystalline cellulose (MCC) is one of the cellulose derivatives produced as a result of the depolymerization of a part of cellulose to achieve high crystallinity. When implemented in other polymers, high crystallinity correlates with greater strength and stiffnes, but it can reduce the water-holding capacity. The acid concentration and hydrolysis time will affect the acquisition of crystallinity and water absorption capacity, both of which have significance as properties of hydrogel filler. The study aimed to evaluate the properties and select the MCC generated from varying the proportion of hydrochloric acid (HCl) and the appropriate hydrolysis… More > Graphic Abstract

R. VENKATESAN^*, S. R. DARSON IMMANUEL JOHN, N. RAJESWARI

Journal of Polymer Materials, Vol.36, No.3, pp. 261-273, 2019, DOI:10.32381/JPM.2019.36.03.6

Abstract Nanocomposite films of chitosan (CH) incorporated with different wt. % of the polyoligomericsilsesquioxane (POSS) were prepared by solution casting. The thermal, mechanical, morphological and antimicrobial properties of the nanocomposites were examined. TGA analyses of the nanocomposites indicate that the filler enables the enhancement of thermal stability of chitosan. The tensile strength of the nanocomposite films is enhanced (10.9 MPa for neat chitosan to 24.0MPa for 5wt. % filled chitosan) by the addition of POSS while the elongation at break is reduced. The nanocomposite films exhibited excellent antimicrobial activity against both gram positive and gram negative More >

ZONGQIAN WANG, HAIWEI YANG, JIAN XING, ZHI LIU^*

Journal of Polymer Materials, Vol.36, No.2, pp. 149-159, 2019, DOI:10.32381/JPM.2019.36.02.4

Abstract Colored silk fibroin (SF) film can change the proportion of transmitted light composition and therefore shows potential application in optoelectronics area. However, few methods are reported for the preparation of colored SF film with good color fastness. Herein, colored SF film was prepared by coupling modification dyeing (CM-dyeing) of SF tyrosine residues in solution. SF film shows excellent color fastness due to the formation of the azo covalent bond formed by electrophilic substitution reaction between SF tyrosine residues and aniline diazonium salt. Furthermore, compared with the undyed film, the dyed SF film is effectively preserved More >

BAOHAI PAN^1,2, JUNCHENG HUANG¹, LAI CHEN², FEI LIU^1,*, CHEN JING, HAINING NA^1,*, JIN ZHU¹

Journal of Polymer Materials, Vol.37, No.1-2, pp. 17-27, 2020, DOI:10.32381/JPM.2020.37.1-2.2

Abstract A switchable CO₂ /1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)/dimethyl sulfoxide (DMSO) solvent system is applied to prepare corn cellulose film with controllable mechanical property. By use of the switchable CO₂ /DBU/DMSO system, a rather simple process concerning reacted dissolution and heated precipitation controlled by addition and releasing of CO₂ respectively, to prepare corn cellulose film, is formed. Results exhibit the degree of dissolution of corn cellulose is easily controlled just by adjusting the feeding amount of DBU in the switchable solvent system. Accordingly, some undissolved part of corn cellulose with relative high crystallinity can be appropriately retained to contribute to the More >

HULYA SEMA KOKER¹, HÜLYA YAVUZ ERSAN¹, AYSE AYTAC^2,3,*

Journal of Polymer Materials, Vol.37, No.3-4, pp. 165-177, 2020, DOI:10.32381/JPM.2020.37.3-4.4

Abstract Chitosan (CH) and low-density polyethylene (PE) blend films were produced by a twin-screw extruder and heat press with different plasticizers glycerol (GLY), sorbitol (SOR) and polyethylene glycol (PEG). The tensile strength decreased and elongation at break increased with the incorporation of plasticizer for blends with 10 wt% of CH. The thermal stability of the films was slightly higher for films containing GLY and PEG as compared to SOR. Contact angles reduced from CH-PE film to the films containing PEG, SOR and GLY in decreasing order, respectively. Fourier transform infrared spectroscopy revealed no interactions between CH More >

DENIZ AKIN SAHBAZ^1,*, BETUL TURP KAYA²

Journal of Polymer Materials, Vol.38, No.3-4, pp. 247-256, 2021, DOI:10.32381/JPM.2021.38.3-4.6

Abstract The objective of this study is to develop chitosan-based films containing Hypericum perforatum L. and/or Citrus limon L. oils and to investigate their suitability as novel wound dressing materials. The morphology of the chitosan-based films were observed by means of employing the scanning electron microscopy (SEM) and the chemical structure characterization was performed via Fourier Transform Infrared Spectroscopy (FTIR). Hypericum perforatum L. and/or Citrus limon L. were successfully incorporated to the chitosan films. Antibacterial, swelling, and mechanical properties of these films were investigated. The antibacterial property was enhanced by incorporating Hypericum perforatum L. and Citrus More >

SOBHA KOTA^*, RATNAKUMARI ANANTHA, VAYUNANDANA RAO GOVADA, PRADEEP DUMPALA

Journal of Polymer Materials, Vol.40, No.3-4, pp. 285-303, 2023, DOI:10.32381/JPM.2023.40.3-4.10

Abstract The exoskeleton of marine shrimp contains a natural, biocompatible polymer chitin, which is dumped as a waste. The study proposes the sustainable single-pot-extraction of chitosan from the waste and its use in the fabrication of wound-dressings, and thus leverage its piezoelectric, antioxidant, hypoglycaemic and medicinal properties in wound-healing. The Fourier transform infrared spectrum revealed that marine chitosan contains functional groups with N-O, O-H, and CO stretching. Scanning electron micrographs demonstrated the spherical and mesoporous structures of the extracted chitosan. X-ray diffraction analysis showed a semi-crystalline phase of chitosan particles with a mean size of 28.9… More >