MOLECULES
·
2022
·Vol. 27
·期 21
·7588
·
IF 4.927
Ge Ma,Qianshu Wang,Jun Ye,Lifan He,Longhai Guo,Xiaoyu Li,Teng Qiu,Xinlin Tuo
The comprehensive balance of the mechanical, interfacial, and environmental requirements of waterborne polyurethane (WPU) has proved challenging, but crucial in the specific application as the binder for high-performance polymer fiber composites. In this work, a multi-step chain extension (MCE) method was demonstrated using three kinds of small extenders and one kind of macro-chain extender (CE) for different chain extension steps. One dihydroxyl blocked small molecular urea (1,3-dimethylolurea, DMU) was applied as one of the CEs and, through the hybrid macrodiol/diamine systems of polyether, polyester, and polysiloxane, the WPU was developed by the step-by-step optimization on each chain extending reaction via the characterization on the H-bonding association, microphase separation, and mechanical properties. The best performance was achieved when the ratio of polyether/polyester was controlled at 6:4, while 2% of DMU and 1% of polysiloxane diamine was incorporated in the third and fourth chain extension steps, respectively. Under the condition, the WPU exhibited not only excellent tensile strength of 30 MPa, elongation of break of about 1300%, and hydrophobicity indicated by the water contact angle of 98°, but also effective interfacial adhesion topara-aramid fabrics. The peeling strength of the joint based on the polysiloxane incorporated WPU after four steps of chain extension was 430% higher than that prepared through only two steps of chain extension. Moreover, about 44% of the peeling strength was sustained after the joint had been boiling for 40 min in water, suggesting the potential application for high-performance fabric composites.Keywords:waterborne polyurethane;chain extension;binder;para-aramid
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2016
·Vol. 34
·期 9
·1070-1078
·
IF 1.811
Feng Li-dong,Xiang Sheng,Sun Bin,Liu Yan-long,Sun Zhi-qiang,Bian Xin-chao,Li Gao,Chen Xue-si
Poly(ether urethane)s (PEU), including PEUI15 and PEUH15, were prepared through chain-extension reaction of poly(ethylene glycol) (PEG-1500) using diisocyanate as a chain extender, including isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI). These PEUs were used to toughen polylactide (PLA) by physical and reactive blending. Thermal, morphological, mechanical and aging properties of the blends were investigated in detail. These PEUs were partially compatible with PLA. The elongation at break of the reactive blends in the presence of triphenyl phosphate (TPP) for PLA with PEUH15 or PEUI15 was much higher than that of the physical blends. The aging test was carried out at -20 °C for 50 h in order to accelerate the crystallization of PEUs. The PEUs in the PLA/PEU blends produced crystallization and formed new phase separation with PLA, resulting in the declined toughness of blends. Fortunately, under the aging condition, although PEUH15 in blends could also form crystallization, the reactive blend of PLA/PEUH15/TPP(80/20/2) had higher toughness than the other blends. The elongation at break of PLA/PEUH15/TPP(80/20/2) dropped to 287% for the aging blend from 350% for the original blend. The tensile strength and modulus of PLA/PEUH15/TPP blend did not change obviously because of the crystallization of PEUH15.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2021
·
IF 3.383
Lei Hou,Chenyang Xie,Mohan Di,Hongzan Song,Yanfang Liu,Ming-tao Run
In order to prepare white fluorescent polymer materials, poly(ethylene succinate- co -cyclohexane dimethanol) (PESC) emitting blue fluorescence and poly (butylene terephthalate- co -propylene terephthalate) (PBTT) modified with 1,6,7,12-tetrachloroperylene tetracarboxylic acid dianhydride (TTAD) are prepared individually by melt polycondensation. Then the two polymers were linked to form a block polymer PESC- b -PBTT by chain extension reaction. The chemical structure, fluorescence emission and crystallization melting behavior of copolyesters are characterized by nuclear magnetic resonance (1H NMR), fluorescence spectrophotometer and differential scanning calorimetry (DSC). The effect of the ratio of PESC and PBTT in PESC- b -PBTT on the fluorescence properties of the products is discussed. The results shows that the fluorescence color of the material can be controlled by adjusting the proportion of each block in the PESC- b -PBTT copolymer. When the PESC’s content reaches 85wt%, the product emits white fluorescence which can be controlled by isothermal crystallization. Attributed to the increase of crystallinity and crystal size caused by the rise of isothermal crystallization temperature, blocking the energy transfer of blue light unit to orange light unit, the fluorescence of the sample turns to cool white gradually.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2024
·
IF 4.1
Tiancheng Dai,Chao Yi,Shuohong Dong,Mingjie Zhang,Chao Long,Zhen Li,Wenkai Liu,Feng Luo,Jiehua Li,Hong Tan
This study incorporated polydimethylsiloxane (PDMS) and a kind of siloxane-based chain extender (SDO) into polyether urethanes (PEU). The correlation between microphase separation structure and mechanical properties, surface properties and wear resistance were investigated using multiple characterization techniques such as DSC , DMA , SAXS, ATR-FTIR, and XPS . The addition of PDMS significantly reduced the friction coefficient of PEU and enhances the hydrophobicity . The addition of SDO helped to improve the compatibility between PDMS and hard segments of PEU as proved by the fact that the glass transition temperatures of PDMS segments were shifted to higher temperatures and the fraction of loosely hydrogen-bonded carbonyls increased. Due to the improved interfacial adhesion between the immiscible segments, the wear resistance of PEU modified by both PDMS and SDO was obviously enhanced.
研究领域:
材料科学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 3.6
Shufang Wu,Zhiqian Long,Yushu Zhang,Ting Zhang,Qinghong Luo,Xiaoxuan Liu,Zhiquan Li
Using low catalyst loadings while maintaining precise polymer property control is a critical challenge in the O-ATRP field. Herein, we report a novel O-ATRP system utilizing 1-bromopyrene (Py-Br) as a photoredox catalyst, enabling controlled polymerization of methyl methacrylate (MMA) at an ultra-low loading of 10 ppm. When combined with ethyl α -bromophenylacetate (EBPA) as an initiator, this system produces polymers with a molecular weight distribution of 1.48 and an initiation efficiency of 66.7%. Mechanistic studies, including UV–Vis spectroscopy, fluorescence spectroscopy, cyclic voltammetry, and time-resolved fluorescence measurements, elucidate the photophysical and photochemical properties of Py-Br in O-ATRP. Kinetic analyses reveal first-order polymerization kinetics, while the linear increase of molecular weight with monomer conversion and low dispersity values indicate good control over the polymerization. The living nature of the system is further confirmed through successful chain extension experiments. This Py-Br-catalyzed O-ATRP system explores the feasibility of conducting polymerization at lower catalyst concentrations, offering insights into approaches for reducing catalyst usage in polymer synthesis. Graphical Photoinduced metal-free ATRP of MMA using ppm-level Py-Br as the organic photocatalyst.
研究领域:
高分子化学
·
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Xiwen Jia,Jiajie Xu,Luoyang Liu,Xueyan Liang,Yinghui He,Lujia Han,Weihua Xiao
In this study, corn stover-based sugar served as the initial carbon source to investigate the impact of different co-culture strategies on the synthesis of short- and medium-chain fatty acids (SMCFAs) through carbon chain elongation (CCE). The results indicated that the sequential inoculation outperformed simultaneous inoculation in the M. elsdenii and Lactobacillus groups. The inclusion of Lactobacillus significantly enhanced substrate utilization, generating lactate that facilitated the integration of odd carbon carboxylates (such as propionate and valerate) into the CCE products. The caproate concentration in the M. elsdenii + L. pentosus group reached 3.4 g/L, which was 1.3 times that in the control group. Furthermore, the introduction of C. kluyveri effectively boosted the synthesis of butyrate and caproate through CCE using ethanol as an electron donor within the co-culture setup of the M. elsdenii+C. kluyveri group. Moreover, the carbon efficiency of the co-culture group increased by 10–21 % compared to the control group, and the cell protein titer was 1.5–2 times higher than that of the control group. This study has established a method for co-producing SMCFAs and cell proteins utilizing bio-sugars through a co-culture approach, offering implications for lignocellulose utilization and potential high-value applications of SMCFAs in the future.
研究领域:
微生物学
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生物化学
·
可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Jianan Cai,Zhipeng Liu,Bo Cao,Xiaoxiao Guan,Shumei Liu,Jianqing Zhao
Simultaneously improving the mechanical properties and processability of polyamide-6 (PA6) by chain extension in melting extrusion is usually very difficult. To address this issue, a novel small-molecule triepoxy chain extender (D1) is designed, synthesized, and used to modify PA6. The rheological measurements show that the shear viscosity of PA6 containing 2 wt % D1 decreases by 52.2% compared with that of the original PA6 at a shear rate of 1000 s–1, which is in the shear rate range of thermoplastic processing in the industry. This interesting result is attributed to the generation of a long-chain-branched structure of the macromolecular chains of chain-extended PA6, which reduces the power-law index and aggravates the shear-thinning behavior of the PA6 melt. In addition, the corresponding notched impact strength increases from 62.4 to 105.9 J/m. As a result, this work provides a feasible way to prepare PA6 with excellent mechanical properties and processability in industrial production.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Maojiang Yue,Guangju Qiu,Li Wang,Wantai Yang
The synthesis and application of thickening polymers for aqueous solutions are crucial in a multitude of industries. Herein, we propose the 4-dimethylaminopyridine (DMAP)-catalyzed esterification reaction between poly(styrene-alt-maleic anhydride) (SMA) and sugar (alcohol) for preparing a new type of thickening polymer. A thorough investigation of the esterification kinetics of SMA and sorbitol as well as the average reacted hydroxyl number (Ne) of sorbitol was conducted by a combination of Fourier transform infrared spectroscopy (FT-IR) and potentiometric titration. The present method can be extended to sugars, including sucrose and maltose, thus delivering SMA-g-sugar (alcohol) with diverse structures. The apparent viscosity of aqueous solutions thickened by SMA-g-sugar (alcohol) before and after further chain extension with diamine was evaluated by using a rotational rheometer. After chain extension with polyetheramine D230, great thickening property and excellent stability against thermal cycles and shear time can be achieved. The present method has broad compatibility, controllable polymer structure, and possibility for further chain extension, thus holding great prospect for preparing thickening polymers applied across different industrial sectors.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Jinrui Hu,Xiao Xu,XinYi Cao,Lulu Dong,Lixia Bao,Weibo Kong,Jiliang Wang
The recycling of poly(ethylene terephthalate) (PET) is vital for environmental sustainability, yet achieving recycled PET (rPET) and its composites with optimal processability and flexibility remains a challenge. This study presents a solvent-free reactive extrusion method to extend the chains of rPET using a macromolecular chain extender (i.e., methyl methacrylate-glycidyl methacrylate copolymer, marked as PMG) rich in epoxy groups and to produce rPET/recycled polyethylene (rPET/rPE) composites. The resulting composites exhibit excellent thermoplasticity and controllable mechanical properties, such as the rPET/rPE composite (70:30 by mass), with a tensile strength of 39.2 MPa and an elongation at a break of 81.4%. After five extrusion cycles, their mechanical properties just encounter a subtle decline, indicating robust sustainability and cycle performance. The formation of a dynamic physical cross-linking network arises from the distinct polarity, hydrophobicity, and melt viscosity of rPET and rPE, where the hard spherical rPET phase is evenly dispersed in the soft rPE matrix with PMG acting as an interfacial compatibilizer. This innovative approach not only enhances the properties of the recycled composites but also promotes their cost-effectiveness and environmental benefits, thus broadening the potential applications of rPET and rPE as partial substitutes for virgin PET and PE.
研究领域:
材料科学
·
环境科学
·
聚合物工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2025
·
IF 5.7
Qianshu Wang,Wenbo Luan,Xiaodong Sui,Qi Sun,Mengyu Zhang,Longhai Guo,Jun Ye,Teng Qiu,Xinlin Tuo
The integration of self-healing properties into waterborne polyurethane (WPU) represents a significant advancement in materials chemistry. However, the practical application of self-healing WPU is often hindered by its compromised toughness, flexibility, and water resistance, as well as the challenges accompanied by complex production processes and high manufacturing costs. In this study, we propose a novel network optimization strategy that leverages the synergistic effects of multiple lateral hydrogen bonds from amide (A)–urea (U) motifs, hydrophobic aggregation of non-crystalline flexible alkyl segments, branched topology, and intrinsic intermolecular interactions within WPU. This strategy is implemented through a straightforward, stepwise chain extension synthesis of WPU, incorporating a biomass-derived chain extender (CA) designed from the condensation of cost-effective dimer acid and pentylenediamine. Remarkably, the optimized WPU exhibited bio-elastic tissue-like properties, including self-healing capability, high strength, toughness, ductility, low modulus and minimal water absorption. The self-healed material, derived from recycled film fragments, achieves an ultimate tensile strength of 41.4 MPa and an elongation at break of 1040%, with no significant stiffening or loss of elasticity. Additionally, the material demonstrated excellent interfacial adhesion, conductivity and strain sensitivity, making it suitable for use as a conductive elastomer. Furthermore, when plasticized with electrolytes, the material exhibited room-temperature self-healing within the conductive network, providing broad potential for applications in flexible electronics and related fields.
研究领域:
材料科学
·
化学工程
·
生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Yanna Zhao,Yiqing Li,Shuai Yang,Yingying Zhang,Xiaowei Bai
This study reports on a polyurethane nanocomposite containing dynamic borate bonds (containing boron and nitrogen endocoordination) with three different nanoparticles as reinforcing fillers. First, a bis-boron nitrogen coordinated borate ester bonded diol (TB–OH) was synthesized and introduced into the polyurethane prepolymer as a chain extender, followed by the addition of a cross-linking agent to form a reticulated cross-linking structure, and finally, the nanoparticles were dispersed into the polymer matrix by the blending method. Among them, the TB-Ca sample had a maximum tensile strength as high as 15.23 MPa, which was 529% higher than that of TB-0, and the Td5% experienced an elevation from 234 to 275 °C. It also showed excellent self-healing performance, achieving a self-healing rate of 83.53% and up to 12.69 MPa when repaired.
研究领域:
材料科学
·
高分子化学
·
纳米技术
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS RESEARCH
·
2021
·Vol. 36
·期 15
·3134-3144
·
IF 3.089
Chang Beizhe,Li Yingchun,Wang Wensheng,Song Gang,Lin Jing,Murugadoss Vignesh,Naik Nithesh,Guo Zhanhu
To improve comprehensive properties of poly(butylene adipate-co-terephthalate) (PBAT), especially thermal stability, reactive extrusion method was used to modify PBAT. Branch and micro cross-linking structure of PBTA was produced with hexanediol diglycidyl ether (HDGE), polyethylene glycol diglycidyl ether (PEGDGE), and styrene–methyl methacrylate–glycidyl methacrylate terpolymer (KL-E4370) as the chain extender (CE), demonstrated through differential scanning calorimeter, Vicat softening point testing (VSP), gel permeation chromatography, rheological measurement, and scanning electron microscopy. The molecular weight, the complex viscosity, and the viscoelasticity of modified PBAT were improved by increasing the CE molecular weight. The crystallization temperature and VSP were also increased. Meanwhile, it showed that the hydrolysis resistance of PBAT was improved and its degradation performance was decreased. Furthermore, when KL-E4370 was added, PBAT has the best comprehensive performance. Graphic abstract
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）