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Reprocessible Epoxy Networks with Tunable Physical Properties:Synthesis,Stress Relaxation and Recyclability

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Chinese Journal of Polymer Science 2018年第5期36卷 641-648页

作者： Jia-Hui Chen Xu-Pei An Yi-Dong Li Ming Wang jian-bing zeng School of Chemistry and Chemical Engineering Southwest University

In order to extend the application of epoxy vitrimer, 1,4-cyclohexanedicarboxylic acid（CHDA） was used as a co-curing agent and structure modifier for sebacic acid（SA） cured diglycidyl ether of bisphenol A（DGEBA） epoxy vitrimer to tailor the mechanical properties of epoxy vitrimers with 1,5,7-triazabicylo[4.4.0]dec-5-ene（TBD） as a transesterification catalyst. The glass transition temperature（Tg） of vitrimer increased gradually with the increase in CHDA content. Vitrimers behaved from elastomer to tough and hard plastics were successfully achieved by varying the feed ratio of CHDA to SA. Both the Young＇s modulus and storage modulus increased apparently with the increase in CHDA content. Stress relaxation measurement indicated that more prominent stress relaxation occurred at elevated temperatures and the stress relaxation decreased with the increase of CHDA content due to the reduced mobility of the vitrimer backbone. The vitrimers showed excellent recyclability as evidenced by the unchanged gel fraction and mechanical properties after compression molded for several times. With tunable mechanical properties, the epoxy vitrimers may find extensive potential applications.

关键词： Epoxy vitrimer Mechanical properties Stress-relaxation Recyclability

Unlocking the Potential of Poly(butylene succinate)through Incorporation of Vitrimeric Network Based on Dynamic Imine Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1414-1424,I0006页

作者： Shan-Song Wu Hui-Juan Lu Yi-Dong Li Shui-Dong Zhang jian-bing zeng Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing400715China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510640China

Poly(butylene succinate)(PBS)exhibits many advantages,such as renewability,biodegradability,and impressive thermal and mechanical properties,but is limited by the low melt viscosity and strength resulted from the linear *** address this,vitrimeric network was introduced to synthesize PBS vitrimers(PBSVs)based on dynamic imine bonds through melt polymerization of hydroxyl-terminated PBS with vanillin derived imine containing compound and hexamethylene diisocyanate using trimethylolpropane as a crosslinking *** with different crosslinking degrees were synthesized through changing the content of the crosslinking *** effect of crosslinking degree on the thermal,theological,mechanical properties,and stress relaxation behavior of the PBSVs was studied in *** results demonstrated that the melt viscosity,melt strength,and heat resistance were enhanced substantially without obvious depression in crystallizability,thermal stability,and mechanical properties through increasing crosslinking *** addition,the PBSVs exhibit thermal reprocessability with mechanical properties recovered by more than 90%even after processing for three ***,PBSV with improved melt properties shows significantly improved foamability compared to commercial *** research contributes to the advancement of polymer technology by successfully developing PBS vitrimers with improved properties,showcasing their potential applications in sustainable and biodegradable materials.

关键词： Poly(butylene succinate) Vitrimer Imine bonds Foamability

Selective fusion in adolescent idiopathic scoliosis

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Chinese Medical Journal 2008年第15期121卷 1456-1461页

作者： WANG Ting XU jian-guang zeng bing-fang Department of Orthopedics Sixth People's Hospital Affiliated to Shanghai Jiao Tong University Shanghai 200233 China

Despite the continual evolution in the surgical treatment of adolescent idiopathic scoliosis （AIS）,the goals of surgery remain to correct and stabilize the deformity in three dimensions, to maintain equilibrium of the shoulders and trunk, and to leave as many mobile spinal segments as possible. The essence is to fuse the smallest possible number of vertebrae to maintain maximum residual mobility, but end with corrected and well-balanced spine. Selective fusion is termed when both the main thoracic and thoracolumbar/lumbar （TL/L） curves deviate completely from the midline （Figure 1）, but only the major curve （the largest Cobb measurement） is fused, leaving the minor curve unfused and mobile. For the single curve, such as thoracic, thoracolumbar, or lumbar curve, there are fewer differences of opinion amongst spinal surgeons regarding the selection of the fusion level than the surgical approach. However, the choice of fusion levels in some types of curves, such as double curves and triple controversy issue. If the fusion is incorrect, it curvature deterioration, curves remains a difficult and decision to perform selective may result in postoperative shoulder imbalance, trunk decompensation, or even produce new deformity, an early revision by extending the fusion or reducing the correction may need. The non-selective approach rarely leads to early troubles that require a second procedure and is often perceived as being safer in the short-term. But it may be more difficult in the long-term as distal degeneration is more likely. This raises the question：＂Is it better to be safe in the short-term or take a chance avoiding later degenerative problems with a shorter motion-sparing fusion？＂ Thus, the aim of selective fusion is to identify the compensatory curves （minor curve） that will straighten spontaneously after correcting and fusing the major curve, thereby avoid the fusion of these flexible compensatory curves.

关键词： adolescent idiopathic scoliosis selective fusion surgery

Rational design of sustainable polyurethanes from castor oil: towards simultaneous reinforcement and toughening

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Science China Materials 2018年第7期61卷 993-1000页

作者： Xu-Pei An Jia-Hui Chen Yi-Dong Li jiang Zhu jian-bing zeng School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China College of Materials and Chemical Engineering Chongqing University of Arts and Sciences Chongqing 402160 China

Sustainable polyurethanes prepared from castor oil and diisocyanates show very low strength and toughness, due to the highly cross-linked and flexible structure. Herein, we report a new strategy to simultaneously reinforce and toughen castor oil-based polyurethane via incorporating a stiff component （isosorbide, IS） to enhance network stiffness and reduce crosslink density. The crosslinking degree de- creases while the strength, moduli, ductility and heat re- sistance significantly increase accordingly with increasing IS content. The tensile behaviors are tunable over a broad range （either as elastomers or as plastics） depending on the com- positions. The polyurethanes show excellent thermal stability with onset decomposition temperature higher than 280℃. The investigation provides a new hint for future design and fab- rication of high performance sustainable polymers from other vegetable oils.

关键词： sustainable polyurethane castor oil isosorbide crosslink density mechanical property

Fully bio-based,highly toughened and heat-resistant poly(L-lactide) ternary blends via dynamic vulcanization with poly(D-lactide) and unsaturated bioelastomer

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Science China Materials 2017年第10期60卷 1008-1022页

作者： Wan-Jie Si Xu-Pei An jian-bing zeng Yu-Kun Chen Yu-Zhong Wang School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China Key Laboratory of Polymer Processing Engineering Ministry of Education South China University of Technology Guangzhou 510641 China Center for Degradable and Flame-Retardant Polymeric Materials College of Chemistry State Key Laboratory of Polymer Materials Engineering National Engineering Laboratory of Eco-Friendly Polymeric Materials （Sichuan） Sichuan University Chengdu 610064 China

Inherent brittleness and low heat resistance are the two major obstacles that hinder the wide applications of poly（L-lactide）（PLLA）. In this study,we report a fully biobased,highly toughened and heat-resistant PLLA ternary blend,which was prepared by dynamic vulcanization of PLLA with poly（D-lactide）（PDLA） and an unsaturated bioelastomer（UBE）. The results indicated that during dynamic vulcanization PDLA cocrystallized with PLLA to form stereocomplex（SC） crystallites,which not only enhanced the molecular entanglement but also accelerated the crystallization rate of PLLA matrix. With increase in the content of PDLA,the matrix molecular entanglement increased while phase-separation was enhanced,which enabled the impact strength to increase first and then decrease. The ternary blends containing 10 wt.% PDLA showed the highest impact strength. The presence of SC crystallites makes it possible to achieve a fully sustainable PLLA/VUB/PDLA ternary blend with highly crystalline matrix under conventional injection molding,due to the high nucleation efficiency of SC towards crystallization of PLLA. The highly crystalline ternary blend showed excellent heat resistance and better impact toughness than high impact polystyrene.

关键词： poly(L-lactide) poly(D-lactide) dynamic vulcanization toughness heat resistance

Transforaminal Lumbar Interbody Fusion for Traumatic Lumbar Spondylolisthesis

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Journal of Shanghai Jiaotong university(Science) 2010年第5期15卷 626-631页

作者：徐建广曾炳芳孔维清周蔚付一山赵必增张涛连小峰 Spinal Surgery Unit Orthopaedic Departmentthe Sixth People's Hospital Affiliated to Shanghai Jiaotong University

To evaluate the clinical outcome,effectiveness and safety of the surgical management of traumatic lumbar spondylolisthesis with transforaminal lumbar interbody fusion (TLIF) with short segmental instrumentation fixation.A retrospective review of a consecutive series of 24 patients with traumatic lumbar spondylolisthesis treated with TLIF procedure was carried *** spinal cord monitoring was used to confirm the peripheral neural function intact during the reduction of the *** clinical and radiographic evaluation of all cases were originally collected *** regarding blood loss,operative time,duration of hospital stay,radiographic fusion,instrumentation failure and clinical result were collected and observed at regular follow-up *** patients were engaged in high-energy accidents in the lower back and 16 patients had concomitant *** mean operative time was 124 min,mean blood loss was 350 mL,and mean hospital stay was 6.5 *** were no complications such as incision infection,cerebrospinal fluide (CSF) leakage and nerve root injury and so *** patients demonstrated a solid lumbar interbody fusion within 4 months,and no evidence of spondylolisthesis correction loss,instrumentation failure and *** all were completely asymptomatic,with normal neurologic findings,and had resumed their previous level of physical activities on the final *** clinical examination and careful imaging assessment could assist an early diagonosis in cases of traumatic lumbar *** open reduction and the TLIF procedure as soon as possible could restore segmental stability and painless *** TLIF procedure was a safe,effective technique to treat traumatic lumbar spondylolisthesis.

关键词： trauma spondylolisthesis lumbar fusion transforaminal lumbar interbody fusion (TLIF)

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang bing Zhang Lanfang Li Xiaomei Tang Jinyu zeng Yige Song Chao Xu Kai Zhao Guoqiang Liu Youming Lu Xinyan Li Kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

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水泥喷浆桩在污水处理工程中的应用

施工技术 2003年第5期32卷 47-48页

作者：李平先高健磊李冰曾科郑州大学环境与水利学院河南郑州450002

水泥喷浆桩根据工程地质条件,将水泥和外加剂混合制成水泥浆,通过机械压力将水泥浆均匀注入土体,利用水泥与土体产生一系列物理化学反应形成由水泥土桩和桩周土共同组成的水泥喷浆桩复合地基,承担基础传来的荷载.这种地基处理方法具有... 详细信息

水泥喷浆桩根据工程地质条件,将水泥和外加剂混合制成水泥浆,通过机械压力将水泥浆均匀注入土体,利用水泥与土体产生一系列物理化学反应形成由水泥土桩和桩周土共同组成的水泥喷浆桩复合地基,承担基础传来的荷载.这种地基处理方法具有施工速度快、工期短、无大的噪声和振动、施工质量容易控制等优点.

关键词：水泥喷浆桩污水处理工程工程地质荷载防水层

Effect of Co-solvent on the Palladium Catalyzed Alkoxycarbonylation of Allyl Bromide in Supercritical CO_2

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Chinese Chemical Letters 2002年第10期13卷 933-934页

作者： Rui Qi SONG jian Qing zeng bing ZHONG Guangzhou Institute of Chemistry Chinese Academy of SciencesGuangzhou 510650 State Key Laboratory of Coal Chemistry Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001 School of Chemistry and ChemicalEngineering Zhongshan University Guangzhou 510275

The effect of cosolvent on the palladium catalyst which catalyze alkoxycarbonylation of allyl bromide in supercritical CO2 has been investigated. It was found that a small amount of cosolvent such as ethanol, CH2Cl2 and cyclohexane can affect both reaction yields and selectivities largely. Ethanol was the most favorable cosolvent for increasing the total yield of unsaturated esters and the selectivity of 3-butenoic acid ester. Using cosolvent ethanol and cocatalyst FeCl2 Simultaneously can lead to better reaction results.

关键词： Supercritical CO2 cosolvent alkoxycarbonylation palladium cocatalyst FeCl2.