ACS Applied Polymer Materials
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2024
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IF 4.4
Shan Jiang,Li Liu
Poly(hydroxyurethane)s (PHUs) are regarded as one of the most promising nonisocyanate-based polyurethanes, with their improved performance attracting widespread attention. As a type of PHU, poly(hydroxyurethane-urea)s (PHUUs) can effectively broaden the performance range of PHUs, demonstrating high potential for various applications. In this study, cross-linked PHUU elastomers were prepared through aminolysis of cyclic carbonate, using carbon dioxide-based tricyclic carbonate of glycerol (GTC) as the cross-linker, and carbon dioxide-based amino-terminal polyurea oligomer (TTD*/HMDA*) as the chain extender. The cross-linking density and thermal and mechanical properties of the PHUU elastomers could be tailored by controlling the feed ratio of GTC or TTD*/HMDA*. The reprocessability of the PHUUs was also investigated. To further optimize the properties of PHUUs, modified PHUUs with improved cross-linking density were prepared utilizing pendant hydroxyl groups as cross-linking points. Methacrylic acid (MA) was grafted onto the hydroxyl group, and simultaneously, a dense cross-linking network of the modified PHUUs was formed through the polymerization of MA. With the introduction of MA, modified PHUUs showed an increased glass transition temperature and adjustable mechanical properties. The tensile strength, Young’s modulus, and elongation at break of modified PHUUs were in the ranges of 1.19–15.00 MPa, 0.69–95.65 MPa, and 138–687%, respectively. Modified PHUUs exhibited significantly improved tensile strength and Young’s modulus than those of PHUUs. This work provides an option for preparing high-performance or functionalized PHUUs.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
POLYMER
·
2022
·
IF 4.432
Shan Jiang,Li Liu
Poly(hydroxyurethane-urea)s (PHUUs), which have complementary thermal and mechanical properties with poly(hydroxyurethane)s (PHUs) and polyureas, are of great potential for practical applications. Herein, several novel PHUUs were synthesized through polyaddition reaction from 5-membered dicyclic carbonates and amino-terminal polyurea oligomers , and corresponding PHUs were also synthesized as controls. It was worth noting that carbon dioxide was starting materials in the synthesis of both 5-membered dicyclic carbonates and amino-terminal polyurea oligomers. The structures and properties of PHUUs and PHUs were characterized by FTIR , 1 H NMR, SEC , water contact angle measurement, TGA , DSC , and tensile test. The urethane-to-urea ratio of PHUUs depended on the diamines used in the synthesis of amino-terminal polyurea oligomers. With the introduction of urea moieties, PHUUs exhibited improved surface hydrophobicity and thermal properties. Meanwhile, the introduction of urea moieties and the structure of selected diamine influenced glass transition temperature (T g ) and mechanical properties of PHUUs. This work offered a fascinating option for preparing PHUUs and might contribute to tackling climate change.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Advanced Photonics Research
·
2021
·Vol. 2
·期 5
·2000161
·
IF 0
Bin Liu,Zheng Chen,Bo Chu,Ya-Ling Wang,Ning Li,Huinian Zhang,Yongzhen Yang,Shengliang Hu,Xing-Hong Zhang
Despite the advancements in synthetic methods, it is still challenging to prepare white light-emitting carbon dots for solid-state white light-emitting diodes (LEDs). Herein, the synthesis and characterization of a carbonized polymer dot (CPD) that emits white light in the solid state are presented. The reaction of an oxygen-rich precursor, trimethylolpropane tri(cyclic carbonate) ether, with nitrogen-rich melamine in an alcohol via a single-step solvothermal method affords CPDs with hydroxyurethane and CN groups. The morphology of the CPDs can be regulated by changing the reaction time. Transmission electron microscopy reveals structural evolution from flocculent polymers to dandelion-like and spherical particles with an increase in the carbonization time from 6 to 12 and 18 h, respectively. The dandelion-like CPDs exhibit a relatively high quantum yield of 7.5% in the solid state, which is ascribed to the abundant surface poly(hydroxyurethane) chains that restrict the aggregation-caused quenching of luminescence. It is proposed that multiple coexistent clusters generate different emission sites, thereby leading to white light emission. Loose clusters formed from hydroxyurethane and CN bonds, which have a low degree of conjugation, emit blue light, whereas compact clusters generated through interactions between the hydroxyurethane and CN bonds of poly(hydroxyurethane) and carbon cores emit yellow light.
研究领域:
材料科学
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光学
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DOI
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Xiuxiu Liu,Xinxin Yang,Siheng Wang,Shibo Wang,Zhiping Wang,Shiwei Liu,Xu Xu,He Liu,Zhanqian Song
Polyhydroxyurethanes (PHUs), polyurethanes with excellent properties, are cured without poisonous isocyanate. The carbamate groups in the structure can undergo bond exchange in the presence of amino groups to improve their reprocessing and recyclability. As the demand for more “sustainable” polymers increases, research has focused on replacing fossil materials with renewable alternatives. 1,8-Menthane diamine (MDA) derived from turpentine is a potential raw material for curing with cyclic-carbonated soybean oil (CSBO) for preparing fully bio-based PHUs without solvents and catalysts. The amino groups from MDA facilitate bond exchange under autocatalysis in PHUs, and the rigid structure improves the thermal and mechanical properties of PHUs. PHUs with different cyclic carbonate/amino ratios are characterized to explain the importance of MDA in the performance of PHUs. Dynamic covalent bond exchange was studied through stress relaxation, which results in self-healing, recyclability, reprocessing, and shape memory. The mechanical properties and thermal stability can be almost completely recovered (>85%) after reprocessing several times, indicating that the network will be repaired by bond exchange. This work provides a promising strategy to utilize sustainable feedstocks for designing fully bio-based non-isocyanate polyurethanes and reveals the effect of the structure on the material properties.
研究领域:
材料科学
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化学工程
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可持续发展
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产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2024
·
IF 4.5
Muhammad Usman Saeed,Guohua Hang,Yuan Gao,Jiawei Hu,Lei Li,Tao Zhang,Sixun Zheng
Poly(N-vinyl pyrrolidone) (PVPy) chains were grafted onto the surfaces of barium titanate (BaTiO 3) nanoparticles via the surface-initiated living/controlled radical polymerization of N-vinyl pyrrolidone. The PVPy-grafted BaTiO 3 nanoparticles were then incorporated into a crosslinked polyhydroxyurethane (PHU) which was derived from bis(six-membered) cyclic carbonate and a triamine ( i.e., Jeffamine T400). It was found that BaTiO 3 nanoparticles were uniformly dispersed into the PHU matrix. The generation of nanocomposites resulted that the glass transition temperatures ( T g ’s) and mechanical properties were significantly enhanced. In the meantime, the nanocomposites had the dielectric properties superior to control PHU; the shape memory properties of the materials were significantly improved in terms of response, fixity of transient shape and recovery of the original shapes. Thanks to transcarbamoylation of hydroxyurethane structural units, the crosslinked nanocomposites can be reprocessed at elevated temperature. It was found that dibutyltin dilaurate (DBTDL) was an effective catalyst to decrease the Arrhenius activation energy of the dynamic reaction; the reprocessing of the nanocomposites can be carried out at the temperature as low as 120 °C.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 136
·期 37
·47957
·
IF 2.188
Jingtao Dai,Zhijun Wu,Liuyang Tang,Jinqing Qu
Cyclic carbonates reacted with diamines or polyamines have been proposed as a greener and safer method to prepare free isocyanate polyurethane coatings. Here, five kinds of bis(cyclic carbonate)s (TDC: toluene bis(cyclic carbonate), MDC: 4,4′-diphenylmethane bis(cyclic carbonate), IPDC: isophorone bis(cyclic carbonate), HMDC: 4,4′-methylenebis(cyclohexyl cyclic carbonate), HDC: hexamethylene bis(cyclic carbonate)) were prepared by reacting glycerol carbonate with diisocyanate under atmospheric pressure. Their structures were verified by 1 H-NMR and 13 C-NMR. These difunctional cyclic carbonates were then reacted with several amines to prepare new polyhydroxyurethane (PHU) coatings, and the film properties were tested. It was found that PHUs based on aromatic and alicyclic structures including TDC, MDC, IPDC, and HMDC displayed high hardness but had poor flexibility and impact resistance, whereas PHUs based on aliphatic structures such as HDC exhibited good flexibility and impact resistance and low hardness. When the length of the alkyl groups in the amine curing agents increased, the impact resistance and flexibility of the PHUs increased, but their pencil hardness decreased. PHUs from TDC, MDC, and IPDC had excellent chemical resistance, but the PHUs from HMDC and HDC had less chemical resistance. Some films displayed excellent properties including 4H pencil hardness, 100 cm kg impact resistance, and excellent flexibility. Some PHUs exhibited good thermal stability, with T 5% values all above 242°C. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47957.
研究领域:
材料科学
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有机化学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2021
·
IF 4.598
Fang-Yu Ren,Fei You,Song Gao,Wei-Hang Xie,Liang-Nian He,Hong-Ru Li
As a consequence of the great demand and extended application of polyurethanes in various fields, the development of green processes for their production and functional polyurethane materials has received widespread attention. In this regard, the biomass-derived polyurethane via the non-isocyanate route could be promising. In this work, the castor-based polyurethanes were designed and synthesized through a non-isocyanate route by employing ricinoleic acid as the starting material, in which the oligomeric ricinoleic acid (ORA) with variable average polymerization degree was used as the key intermediate. To access the ORA with different average polymerization degree, the solid Lewis acid tin(II) oxide (SnO) was developed as the efficient and recyclable catalyst and the average polymerization degree of ORA was regulated by the reaction time at 210 °C. After sequential esterification, epoxidation, cycloaddition with CO 2 and polyaddition with 1,6-hexamethylene diamine (HMDA) or isophorone diamine (IPDA), a series of polyhydroxyurethanes (PHUs) with different tensile strength and elongation at break as well as the thermal stability and the glass transition temperature were obtained depending on the type of diamine and the average polymerization degree of ORA, indicating the functional role of the polymerization degree of ORA in regulating the mechanical and thermal properties of the resulting materials. This protocol for the castor-based PHUs preparation in this work not only represents a green and sustainable way to produce bio-based material, but also provides a convenient way to change the average polymerization degree of ORA and then alter the properties of resulting polyurethanes.
研究领域:
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）