Kartikey Shahi, Velmurugan Ramachandran^*, Ranjith Mohan, Boomurugan Ramachandran

Journal of Polymer Materials, Vol.42, No.2, pp. 477-496, 2025, DOI:10.32604/jpm.2025.062481 - 14 July 2025

Abstract A Shape Memory Polymer Composite (SMPC) is developed by reinforcing an epoxy-based polymer with randomly oriented short glass fibers. Diverging from previous research, which primarily focused on the hot programming of short glass fiber-based SMPCs, this work explores the potential for programming below the glass transition temperature (Tg) for epoxy-based SMPCs. To mitigate the inherent brittleness of the SMPC during deformation, a linear polymer is incorporated, and a temperature between room temperature and Tg is chosen as the deformation temperature to study the shape memory properties. The findings demonstrate an enhancement in shape fixity and More >

S. U. Atayeva^a,b, A. I. Isayev^a, S. I. Mekhtiyeva^a, S. N. Garibova^a,c,*, R. I. Alekberov^a,d, F. N. Mammadov^e

Chalcogenide Letters, Vol.21, No.4, pp. 355-363, 2024, DOI:10.15251/CL.2024.214.355

Abstract The study is dedicated to the investigation of thermo-physical characteristics of Se₉₅Te₅ chalcogenide glassy semiconductor during its glass formation and crystallization processes, employing various scanning rates of 5, 10, 15 and 20 K/min in non-isothermal modes through DSC measurement. Analysis of the structural relaxation kinetics involves the Kissinger’s, Augis and Bennett's, as well as Matusita’s approaches. Experimental data yield contains the determination of crucial parameters such as glass transition (T_g), crystallization(T_c), and melting temperatures alongside factors like reduced temperature of glass transition (T_rg), Hruby’s parameter (K_gl), fragility index (F_i), Avrami exponents (n, m), glass transition (140.24 kJ/mol) and More >

L. Yang^a,b,c, G. J. Zhou^a,b,c, C. G. Lin^a,b,c,*

Chalcogenide Letters, Vol.20, No.1, pp. 1-9, 2023, DOI:10.15251/CL.2023.201.1

Abstract Ge_12.5Se_87.5-xTe_x (0≤x≤45) glasses were selected for elucidating the composition-dependent properties and network structure of Te-containing glasses. With increasing Te content (x), Vickers hardness (H_v) and glass transition temperature (T_g) initially increased and then decreased, showing a compositional threshold at x=27.5. It is found that the compositional trend of H_v and T_gg is in good accordance with the structural evolution studied by Raman spectra. The results suggest that the introduction of Te leads to the evolution of the network connectivity and average bond strength of Ge_12.5Se_87.5-xTe_x glass structure, which imposes an opposite impact on the structural properties (H_v and T_g). More >

S. Kumar^a,*, P. Kumar^b, S. K. Sahni^c, S. P. Singh^d, K. Singh^e

Chalcogenide Letters, Vol.20, No.6, pp. 393-398, 2023, DOI:10.15251/CL.2023.206.393

Abstract Differential Scanning Calorimetry (DSC) is performed at different heating rates under non-isothermal conditions to study the heat capacities studies of glassy Se₇₅Te_15-XCd₁₀In_X(x=0, 5,10and 15) alloys.Heat capacities of Se₇₅Te_15-XCd₁₀In_X(x=0, 5,10 and 15) chalcogenide glasses at glass transitions (T_g) and crystallisations temperatures (T_c) werementioned in this work. The evaluated endothermic (ΔC_pg) and exothermic (ΔC_pc) heat capacities of Se-Te-Cd-In system varies with alloying concentrations and maximum at threshold composition (5 at wt.% of In). This could be explained on the basis of chemical bond theory of the solids. More >

DIBYENDU S. BAG^*, SHILPI TIWARI, AKANSHA DIXIT, KM. MEENU

Journal of Polymer Materials, Vol.40, No.1-2, pp. 105-123, 2023, DOI:10.32381/JPM.2023.40.1-2.9

Abstract In this paper, we report the microstructural investigation and influence of H-bonding on the thermal behavior e.g., glass transition (T_g ) and thermal degradation of chiral copolymers of (R)- N-(1-phenyl-ethyl) methacrylamide (R-NPEMAM) and 2-hydroxy ethyl methacrylate (HEMA). The T_g increases with the increase of chiral unit content in the copolymers and then attains optimum at around 25 mole % of chiral content. Thereafter it decreases with the increase of chiral content. The effect of copolymer composition and secondary interaction associated with the Hbonding on the thermal properties of these copolymers was also studied. Secondary interaction, specifically More >

Xiao Luo^1,*, Hongying Chu², Mengqi Liu¹

Journal of Renewable Materials, Vol.8, No.10, pp. 1295-1304, 2020, DOI:10.32604/jrm.2020.011026 - 31 August 2020

Abstract Herein, epoxidized soybean oil methyl ester (ESOM) plasticizer was synthesized for the preparation of plasticized poly(vinyl chloride) (PVC) films by the alcoholysis and epoxidation. The chemical structure of ESOM was investigated by infrared spectrum and ¹H nuclear magnetic resonance. The effect of content of ESOM and petroleum based plasticizer di-2-ethylhexyl phthalate (DEHP) on the performance of plasticized PVC films was studied. The result showed that substituting DEHP with ESOM can improve the thermal stability of plasticized PVC films. When the weight ratio of ESOM and PVC is fixed at 1:2, plasticized PVC film presents higher elongation More >

Qiuren Ou^1,2,*, Peijun Ji², Jun Xiao¹, Ling Wu²

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.1, pp. 27-37, 2019, DOI:10.32604/fdmp.2019.04787

Abstract The properties of resin transfer molding (RTM) cyanate ester and its T800 grade carbon fiber composites were studied with the rheometer, differential scanning calorimetry (DSC), FT-IR, dynamic mechanical analyzer (DMA), thermal gravimetric analysis (TGA), mechanical property testing, and scanning electron microscopy (SEM). The results showed that the temperature of cyanate ester suitable for RTM process was 70℃. Curing process of the resin was 130℃/2 h+160℃/2 h+200℃/2 h+220℃/4 h. Glass transition temperature and heat decomposition temperature of the cured resin are 289℃ and 415℃, respectively. Mechanical properties of T800/RTM cyanate composites are 13.5% higher than that More >