Shunjie Liu^1,2, Yusheng Qin^1,*, Xianhong Wang^1,*, Fosong Wang¹

Journal of Renewable Materials, Vol.3, No.2, pp. 101-112, 2015, DOI:10.7569/JRM.2014.634140

Abstract Precursors with sharp crystalline transition temperature have attracted signifi cant attention in the fi eld of shape-memory materials; however, seldom have reports been related to amorphous ones with industrial application prospects. This study introduced a new family of amorphous CO₂ -based hydroxyl-telechelic three-armed oligo(carbonate-ether) triol (Triol) with controllable molecular weight (M_n) and carbonate unit content (CU), which was coupled with PEG and 1,6-hexamethylene diisocyanate (HDI) to afford crosslinked polyurethanes (PU) networks with well-defi ned architecture. A crosslinking point was provided by Triol and PEG was used to afford networks some crystallinity. The resulting networks were characterized using attentuated total refl… More >

Nassibeh Hosseini¹, Samad Javid¹, Ali Amiri¹, Chad Ulven^1,*, Dean C. Webster², Ghodrat Karami¹

Journal of Renewable Materials, Vol.3, No.3, pp. 205-215, 2015, DOI:10.7569/JRM.2015.634112

Abstract In this study, a novel, bio-based polyol was used in the formulation of a polyurethane (PU) matrix for a composite material where fl ax fi ber was used as the reinforcement. The viscoelastic properties of the matrix and fl ax fi ber were determined by a linear viscoelastic model through experimentation and the results were used as input for the material properties in the computational model. A fi nite element micromechanical model of a representative volume element (RVE) in terms of repeating unit cells (RUC) was developed to predict the mechanical properties of composites. Six loading conditions were applied on… More >

Tingting Huo¹, Jiaquan Xue^2,*, Zhi’an Fu³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.2, pp. 437-450, 2023, DOI:10.32604/fdmp.2022.020696

Abstract The properties of polyurethane concrete containing a large amount of fly ash are investigated, and accordingly, a model is introduced to account for the influence of fly ash fineness, water ratio, and loss of ignition (LOI) on its mechanical performances. This research shows that, after optimization, the concrete has a compressive strength of 20.8 MPa, a flexural strength of 3.4 MPa, and a compressive modulus of elasticity of 19.2 GPa. The main factor influencing 28 and 90 d compressive strength is fly ash content, water-binder ratio, and early strength agent content. More >

Samsul Bhakri¹, Muhammad Ghozali^2,*, Edy Cahyono¹, Evi Triwulandari², Witta Kartika Restu², Nissa Nurfajrin Solihat³, Apri Heri Iswanto^4,5, Petar Antov⁶, Viktor Savov⁶, Lee Seng Hua⁷, Erika Ayu Agustiany⁸, Lubos Kristak⁹, Widya Fatriasari^3,*

Journal of Renewable Materials, Vol.11, No.1, pp. 41-59, 2023, DOI:10.32604/jrm.2022.023151

Abstract The aim of this research work was to evaluate the potential of using renewable natural feedstock, i.e., Jatropha curcas oil (JCO) for the synthesis of non-isocyanate polyurethane (NIPU) resin for wood composite applications. Commercial polyurethane (PU) is synthesized through a polycondensation reaction between isocyanate and polyol. However, utilizing toxic and unsustainable isocyanates for obtaining PU could contribute to negative impacts on the environment and human health. Therefore, the development of PU from eco-friendly and sustainable resources without the isocyanate route is required. In this work, tetra-n-butyl ammonium bromide was used as the activator to open the epoxy ring with 3-Aminopropyltriethoxisylane… More > Graphic Abstract

Elham Azadeh¹, Xinyi Chen², Antonio Pizzi^2,*, Christine Gérardin¹, Philip Gérardin¹, Hisham Essawy³

Journal of Renewable Materials, Vol.10, No.12, pp. 3217-3227, 2022, DOI:10.32604/jrm.2022.022740

Abstract Non-isocyanate polyurethane (NIPU) foams using a hydrolysable tannin, also vulgarly called tannic acid, namely here commercial chestnut wood tannin extract was prepared. Compression strength did not appear to depend on the foam apparent density while the formulation composition of the NIPU foams has been shown to be more determinant. These NIPU foams appeared to be self-extinguishing once the high temperature flame is removed. The ignition time gave encouraging results but for improved fire resistance the foams may need some fire-retardant addition. FTIR spectrometry showed the formation of non-isocyanate urethane linkages. Thermogravimetric analysis indicated a good thermal resistance of these foams,… More >

Xuechuan Wang^1,2, Wenying Zhao^1,2, Xugang Dang^1,2,*, Yiqing Wang^1,2, Huijie Zhang^1,2,*

Journal of Renewable Materials, Vol.10, No.11, pp. 2747-2763, 2022, DOI:10.32604/jrm.2022.021555

Abstract As a non-toxic, highly reactive biomass material, gelatin is wildly used as the component of biomass-based adhesive. However, like most aqueous adhesives, gelatin-based adhesives suffer from long solidifying time or high solidifying temperature due to the low volatility of water, which highly limits the application potential of gelatinbased adhesives. Inspired by the fast adhesion of marine organisms through the formation of chemical crosslinks, herein, a kind of low temperature curable eco-friendly gelatin-based adhesive with good adhesive properties and fast curing at low temperature is developed by introducing clicking chemical Diels-Alder (DA) reaction between blocked waterborne polyurethane (MWPU) and gelatin. The… More > Graphic Abstract

Junlong Yao^1,2, Wei Nie¹, Zhengguang Sun², Huan Yang^1,3,*, Yu Guan¹, Lin Gao⁴, Xueliang Jiang¹, Mujie Guo¹, Chuanxi Xiong^5,*

Journal of Renewable Materials, Vol.10, No.9, pp. 2355-2364, 2022, DOI:10.32604/jrm.2022.019339

Abstract In general, self-healing dielectric composites are mainly composed of polar hydrogen bonds, which have high hydrophilicity and are unsuitable for humid environment. Dielectric composite with Diels-Alder (D-A) bond contains covalent bonds, it can be adopted as an efficient self-healing material. Here, we construct self-healing barium titanate (BT)/polyurethane (PU) dielectric composites by adopting PU with D-A bond as matrix (BT/ PU-DA). The prepared 10% BT/PU-DA composite exhibits superior self-healing ability than that of PU-DA. Moreover, its dielectric constant can reach 9.3 with a loss of only 0.04 at 1000 Hz and maintain 93% repair effi- ciency of tensile strength. The experimental… More >

Yuzhuo Wang^1,2, Zhichao Xu^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 897-906, 2022, DOI:10.32604/fdmp.2022.018972

Abstract Polyurethane is enjoying a widespread use as a polymer-based waterproof material in civil engineering In the present study we consider a temperature-sensitive waterproof and moisture-permeable polyurethane material (PTPE-PU) characterized by one or more phase transition temperatures (critical temperatures). Near the critical temperature, the waterproof and moisture permeability of polyurethane undergo abrupt changes. The related stability, thermal performance, water resistance, hydrostatic pressure, and moisture permeability are investigated here considering a PTPE-PU traditionally used in bridge geotechnical engineering. The results show that the moisture permeability of the coated bridge rock and soil undergo sudden variations near the crystallization and melting temperature of… More >

Xing Zhou^*

Journal of Renewable Materials, Vol.10, No.6, pp. 1623-1639, 2022, DOI:10.32604/jrm.2022.018935

Abstract A facile method, focusing on emulsification, chain extension and dispersion process in preparing waterborne polyurethane, was developed to prepare emulsion with rod-like nanoparticles. The facile method involves a water addition procedure by in situ generated water to react with polyurethane prepolymer instead of the external water addition process. As a comparison, waterborne polyurethane was synthesized through the external water addition process. According to the characterization methods including FTIR, ¹H-NMR, TEM and water swelling experiments, it is suggested there are two kinds of hydrogen bonds interactions in hard/soft domain of the novel polyurethane, and the phase separation of hard/soft domains increases… More > Graphic Abstract

Bing Zhang¹, Sujie Yang¹, Mengru Liu¹, Panyue Wen², Xiuyu Liu¹, Gang Tang^1,*, Xiangrong Xu^3,4,*

Journal of Renewable Materials, Vol.10, No.5, pp. 1201-1220, 2022, DOI:10.32604/jrm.2022.018047

Abstract Biomass phytic acid has potential flame retardant value as the main form of phosphorus in plant seeds. In this study, phytate-based flame retardants aluminum phytate (PA-Al) and iron phytate (PA-Fe) were synthesized and characterized. Subsequently, they were introduced into rigid polyurethane foam (RPUF) as flame retardants by one-step water-blown method. The results indicated that RPUF/PA-Fe30 exhibited the highest char residue of 22.1 wt%, significantly higher than 12.4 wt% of RPUF. Cone calorimetry analysis showed that the total heat release (THR) of RPUF/PA-Al30 decreased by 17.0% and total smoke release (TSR) decreased by 22.0% compared with pure RPUF, which were the lowest, demonstrating… More > Graphic Abstract