Laima Vevere^*, Beatrise Sture, Vladimir Yakushin, Mikelis Kirpluks, Ugis Cabulis

Journal of Renewable Materials, Vol.12, No.3, pp. 585-602, 2024, DOI:10.32604/jrm.2024.047350

Abstract Cryogenic insulation material rigid polyurethane (PU) foams were developed using bio-based and recycled feedstock. Polyols obtained from tall oil fatty acids produced as a side stream of wood biomass pulping and recycled polyethylene terephthalate were used to develop rigid PU foam formulations. The 4th generation physical blowing agents with low global warming potential and low ozone depletion potential were used to develop rigid PU foam cryogenic insulation with excellent mechanical and thermal properties. Obtained rigid PU foams had a thermal conductivity coefficient as low as 0.0171 W/m·K and an apparent density of 37–40 kg/m³. The developed rigid PU foams had… More > Graphic Abstract

KRISHAN KUMAR PATEL, RAJESH PUROHIT

Journal of Polymer Materials, Vol.36, No.1, pp. 23-37, 2019, DOI:10.32381/JPM.2019.36.01.3

Abstract Microwave (MV)-induced thermo-responsive shape memory thermoplastic polyurethane (SMTPU)/ MWCNT composites were prepared in micro-compounder. Composites containing different amount of multiwall Carbon nanotube (MWCNT) varying from 0 to 1.5 phr in SMTPU matrix were prepared. Maximum stretching strength, recovery force and tensile strength for 1.5 CNTPU (1.5 phr MWCNT in SMTPU matrix) was increased by 120%, 100% and 24% respectively as compared to SMTPU. MV-induced shape memory is a novel approach for fast, clean and remote heating during operation. MWCNT is strong absorber of microwave irradiation so that SMTPU/ MWCNTs nanocomposites successfully triggered by microwave. More >

S. MATHIVANAN^*, R. MOHAN, RAMES C PANDA, P. BALACHANDER¹

Journal of Polymer Materials, Vol.39, No.3-4, pp. 195-204, 2022, DOI:10.32381/JPM.2022.39.3-4.2

Abstract Optimum-designed footwear with polyurethane (PU) material for comfort is an important requirement for obese. Investigations on compressive behavior of varied designed footwear using 120 D PU material have been carried out. The energy absorption primarily depends on heel height, slope angle and load applied or body mass index of obese. Statistical analysis has been used to formulate the prediction of absorbed energy wherein a heel height of 30 mm with 20-degree angle provides optimum value with the incorporation of 120 D PU material. A coefficientof-determination (R² ) value of 0.9406 confirms the suitability of the statistical regression model. Hence, the… More >

SIVARAJ SUDHAHAR^a,f, UMAMAHESWARI G^b, JAYA PRAKASH ALLA^c, RAGHAVA RAO JONNALAGADDA^d, SUGUNA LAKSHMI^e, SANJEEV GUPTA^f,*

Journal of Polymer Materials, Vol.40, No.1-2, pp. 33-45, 2023, DOI:10.32381/JPM.2023.40.1-2.3

Abstract Leather manufacturing process involves a lot of waste disposal which pollutes environment, some of the processes are inevitable. In the present investigation, 3D printing technology was used to reduce the wastage and to cover defective regions in leather. The present study focuses on synthesis of acrylic binder using emulsion polymerization technique. These binders were analysed for solid content for better optimisation of the amount of binder to be utilised for finishing operation. The experimental binder was prepared with 26% solids. Particle size and thermogravimetric analyses were carried out to understand the size and shape of the particles and their thermal… More >

Fatemeh Hassani Khorshidi¹, Saeed Kazemi Najafi¹, Farhood Najafi^2,*, Antonio Pizzi^3,*, Dick Sandberg⁴, Rabi Behrooz¹

Journal of Renewable Materials, Vol.12, No.2, pp. 305-323, 2024, DOI:10.32604/jrm.2023.043953

Abstract The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin nano-particles. For this purpose, the prepared coatings were applied to pine wood surfaces and weathered artificially. Subsequently, color and gloss of the coatings were measured before and after the weathering test. Field emission scanning electron microscopy (FE-SEM) micrographs prepared from the coatings showed that the average size of nano-particles in the polyurethane substrate was approximately 500 nm. Nuclear magnetic resonance (¹³C-NMR) spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based polyurethane. Differential calorimetric analysis (DSC) test revealed that the glass-transition temperature… More > Graphic Abstract

Lei Yang¹, Guangyan Huang^1,2,*, Tao Wang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09759

Abstract In order to evaluate the blast mitigation effect of polyurethane foam in cylindrical explosion containment vessels (CECVs), a three-dimensional numerical simulation model was established. The Structured Arbitrary Lagrange-Euler (S-ALE) algorithm was applied in current simulations to define the coupling contact between TNT and Lagrange algorithm. The numerical model was verified by comparing the dynamic deformation and permanent deformation of the experiments. Based on the numerical simulation model after verification, the influence of polyurethane foam filling inside CECVs on the mitigation effect was investigated. The results revealed that compared with the ALE algorithm, the numerical simulations based on the S-ALE algorithm… More >

Elham Azadeh¹, Antonio Pizzi^1,2,*, Christine Gerardin-Charbonnier^1,*, Philippe Gerardin¹

Journal of Renewable Materials, Vol.11, No.6, pp. 2823-2848, 2023, DOI:10.32604/jrm.2023.027651

Abstract Non-isocyanate polyurethane (NIPU) foams from a commercial hydrolysable tannin extract, chestnut wood tannin extract, have been prepared to determine what chemical species and products are taking part in the reactions involved. This method is based on two main steps: the reaction with dimethyl carbonate and the formation of urethane bonds by further reaction of the carbonated tannin with a diamine-like hexamethylene diamine. The hydroxyl groups on the tannin polyphenols and on the carbohydrates intimately linked with it and part of a hydrolysable tannin are the groups involved in these reactions. The carbohydrate skeleton of the hydrolysable tannin is also able… More > Graphic Abstract

Saeed Kazemi Najafi¹, Farhood Najafi², Antonio Pizzi^3,*, Fatemeh Hassani Khorshidi^1,*, Rabi Behrooz¹

Journal of Renewable Materials, Vol.11, No.5, pp. 2171-2189, 2023, DOI:10.32604/jrm.2023.027835

Abstract Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms, especially carbon-carbon and carbon-hydrogen. These compounds are mainly used as reactants to make other polymers. Among biopolymers, lignin is regarded as the base of a new polymer in polyol construction. The present study aimed to investigate the effects of amine type (diethylenetriamine and ethylenediamine) on the modification of lignin-based polyols, so as to provide an alternative to petroleum polyols and, in turn, increase functional groups and reduce their harm to humans’ health and the environment. To this aim, first, lignin was extracted from raw… More > Graphic Abstract

Henghui Deng^1,2, Jingyi Lu^1,2, Dunsheng Liang^1,2, Xiaomin Wang^1,2, Tongyao Wang^1,2, Weihao Zhang^1,2, Jing Wang^3,*, Chaoqun Zhang^1,2,*

Journal of Renewable Materials, Vol.11, No.3, pp. 1209-1222, 2023, DOI:10.32604/jrm.2022.023371

Abstract In this study, acrylic acid was used as a neutralizer to prepare bio-based WPU with an interpenetrating polymer network structure by thermally induced free radical emulsion polymerization. The effects of the content of acrylic acid on the properties of the resulting waterborne polyurethane-poly (acrylic acid) (WPU-PAA) dispersion and the films were systematically investigated. The results showed that the cross-linking density of the interpenetrating network polymers was increased and the interlocking structure of the soft and hard phase dislocations in the molecular segments of the double networks was tailored with increasing the content of acrylic acid, leading to enhancement of the… More > Graphic Abstract

Sai Gong^1,2,#, Shanglin Xiang^1,#, Tingwei Wang^1,*, Dongyu Cai^2,*

Journal of Renewable Materials, Vol.11, No.3, pp. 1063-1076, 2023, DOI:10.32604/jrm.2022.023011

Abstract Waterborne polymers are vital for coating industry to reduce carbon emissions. However, formation of robust and self-healable films at ambient temperature remains a challenge owing to high energy cost of film formation process. This work reports a solar-driven film formation of waterborne polyurethanes (WPUs) containing disulfide bonds via in-situ incorporation of 2D titanium carbide (MXene) with ability to convert light to heat. Instead of directly mixed with WPUs, MXene is added to join the reaction with isocyanate-terminated pre-polymer before emulsification process. This approach not only prevents aggregation of MXene in water but stabilizes MXene against thermal degradation which is the… More > Graphic Abstract