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Design of Tough, yet Strong, Heat-resistant PLA/PBAT Blends with Reconfigurable shape memory Behavior by Engineering Exchangeable Covalent Crosslinks

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Chinese Journal of Polymer Science 2023年第12期41卷 1868-1878,I0007页

作者： Xiao-Wen Zhou Jing Huang Xu-Hui Zhang Ting Li Yang Wang Shi-Bo Wang Bi-Hua Xia Wei-Fu Dong The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China

Polylactide(PLA)has often been blended with biodegradable poly(butylene adipate-co-terephthalate)(PBAT)to improve its ***,the strength and heat resistance of PLA are always ***,exchangeable hydroxyl-ester crosslinks are constructed in PLA/PBAT blends by successively introducing a tertiary amine-containing polyol,bis-(2-hydroxyethyl)amino-tris(hydroxymethyl)methane(BTM)and 4,4’-diphenylmethane diisocyanate(MDI)via reactive *** can react with both PLA and PBAT by transesterification,generating PLA or PBAT chains with terminal or pendant hydroxyl groups,which can then react with MDI to form *** internal catalysis of tertiary amine moiety in BTM,transesterification between the residual hydroxyl groups and ester bonds can occur at high temperatures,endowing the PLA/PBAT network with vitrimeric *** to the transesterification and chain extension reactions with MDI between PLA and PBAT,the interfacial adhesion is greatly *** a result of the excellent interfacial adhesion and the network structure,the prepared PLA/PBAT blends show greatly enhanced heat resistance and toughness(more than 40 times that of PLA)while maintaining high stiffness comparable to ***,the prepared PLA/PBAT blends exhibit promising reconfigurable shape memory *** present work provides a new and facile way to achieve high-performance and functional biodegradable polymeric materials.

关键词： Polylactide Dynamic covalent bonds Strengthening and toughening Heat resistance shape memory

3D printed ultra-fast photothermal responsive shape memory hydrogel for microrobots

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International Journal of Extreme Manufacturing 2022年第1期4卷 109-118页

作者： Ziheng Zhan Lei Chen Huigao Duan Yiqin Chen Min He Zhaolong Wang National Research Center for High-Efficiency Grinding College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082People’s Republic of China College of Electrical and Information Engineering Hunan UniversityChangsha 410082People’s Republic of China

Hydrogels with stimuli-responsive capabilities are gaining more and more attention nowadays with prospective applications in biomedical engineering,bioelectronics,microrobot,*** develop a photothermal responsive hydrogel based on N-isopropylacrylamide that achieved a fast and reversible deformation manipulated only by near-infrared(NIR)*** hydrogel was fabricated by the projection micro stereolithography based 3D printing technique,which can rapidly prototype complex 3D ***,with the variation of the grayscale while manufacturing the hydrogel,the deformation of the hydrogel structure can be freely tuned within a few seconds by losing and absorbing water through adjusting the intensity and the irradiation direction of the NIR light,showing a potential application in ultra-fast object grabbing and *** present study provides a new method for designing ultrafast photothermal responsive hydrogel based microrobot working in water.

关键词： hydrogel 3D printing photo-thermal response shape memory microrobot

shape memory of Elastic Capsules Under the Effect of Spontaneous shape

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Communications in Computational Physics 2018年第6期24卷 234-252页

作者： Zhe Gou Feng Huang Xiaodong Ruan Xin Fu State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou 310025P.R.China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhouP.R.China

Red blood cells can recover their resting shape after having been deformed by shear *** rims are always formed by the same part of the membranes,and the cells are said to have *** as two-dimensional elastic capsules,their recoverymotion and shapememory is studied,mainly focused on the effect of the spontaneous *** fluid-structure interaction ismodeled using immersed boundary *** on the simulations,the resting shapes of capsules are obtained and the area ratio of spontaneous shape is found to play an important *** remove of shear flow,all capsules can recover their resting shapes,while only capsules with noncircular spontaneous shapes present shape *** the spontaneous shape approaches a circle but still noncircular,the capsule spends more time on recovery *** consider how these capsules deform depending on the membrane bending energy,and find that the relaxation speed is positive correlated to the range of values of dimensionless bending *** results may help to identify different spontaneous shapes for capsules especially RBCs through future experiments.

关键词： Fluid-structure interaction immersed boundary method shape memory spontaneous shape

Thermal, Mechanical and Electrical Studies of Novel shape memory Polyurethane/Polyaniline Blends

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Chinese Journal of Polymer Science 2015年第9期33卷 1313-1324页

作者： Rabia Sattar Ayesha Kausar Muhammad Siddiq Department of Chemistry Quaid-i-Azam University Nanosciences and Catalysis Division National Centre for Physics Quaid-i-Azam University Campus

shape memory polymer （SMP） blends based on polyurethane （PU） and polyaniline （PANI） were prepared via chemical in situ polymerization process. The thermal, mechanical, electrical and shape memory properties were investigated. The structural characterization and morphology of the polymer blends were inspected by Fourier transform infrared （FTIR） and scanning electron microscopy （SEM）, respectively. The 1 wt% of PANI loading enhanced the thermal stability of the system up to 339 ~C. According to differential scanning calorimetry （DSC）, the glass transition temperature （Tg） and melting temperature （Tm） of PU/PANI blends increased with the polyaniline loading （0.1 wt%-l wt%）. Improved mechanical properties such as tensile strength and Young＇s modulus of PU matrix were also observed with PANI. Moreover, the electrical conductivity of PU/PANI blends was also found to be a function of PANI loading. Remarkable recoverability of thermally triggered shape memory （SM） behavior to the extent of 96% was achieved for 1 wt% PANI blend.

关键词： shape memory Polyurethane Polyaniline Blends Conductivity.

Biodegradable shape memory Polyurethanes with Controllable Trigger Temperature

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Chinese Journal of Polymer Science 2016年第6期34卷 720-729页

作者：顾书英 Xie-feng Gao Sheng-peng Jin Yan-liang Liu School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory of Advanced Civil Engineering Materials Ministry of EducationTongji UniversityShanghai 201804China

A series of random copolymers （PCLAs） were synthesized by ring-opening polymerization of D,L-lactide （LA） and ε-caprolactone （CL） with different molar ratios. PCLA based polyurethanes （PCLAUs） were obtained by chain-extending of PCLA and polytetramethylene ether （PTMEG） with hexamethylene diisocyanate （HDI）. All the PCLAUs exhibit good shape memory properties with high shape fixity ratios above 98% and shape recovery ratios above 82% in the first cycle and 91% in the second cycle. PCLAUs with less CL content show faster recovery speed and PCLAUs with more CL content show higher shape recovery ratio. The trigger temperature can be tuned or controlled around body temperature by adjusting the molar ratio of LA to CL. The PCLAUs have potential applications in implant biomedical devices, especially for minimally invasive deployable devices.

关键词： shape memory Polyurethane Trigger temperature Biodegradable.

THERMALLY STIMULATED shape memory BEHAVIOR OF(ETHYLENE OXIDE-BUTYLENE TEREPHTHALATE)SEGMENTED COPOLYMER

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Chinese Journal of Polymer Science 2000年第4期18卷 357-361页

作者： Xiao-lie Luo Ming-chuan Zhao Mo-zhen Wang Lu-na Ding De-zhu Ma Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China 中国科学技术大学安徽合肥

The thermally stimulated shape memory behavior of ethylene oxide-butylene terephthalate (EOBT) segmented copolymers with different soft segment molecular weight and hard segment content was investigated. The deformation recovery ratio R-f of the EOBT samples increases with the soft segment molecular weight and the hard segment weight content, while the average overall deformation recovery speed V-r increases with the hard segment content. The temperature of maximum deformation recovery speed (T-M) is determined by the melting temperature of the soft segment crystals and the stability of the crystallized hard segment domains.

关键词： ethylene oxide-butylene terephthalate segmented copolymers shape memory crystallized hard segment

The Preparation and Properties of Starch Based shape memory Hydrogel

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Journal of Renewable Materials 2021年第8期9卷 1365-1376页

作者： Yangling Li Zhengrong Li Hui Yu Gang Huang Xiaopeng Pei Kun Xu Pixin Wang Ying Tan School of Textile Materials and Engineering Wuyi UniversityJiangmen529000China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of ScienceChangchun130022China Wenzhou Institute University of Chinese Academy of SciencesWenzhou325001China

In this work,the–catechol and–thiol modified starch was prepared by the esterification and amino condensation reaction,then a fully starch based hydrogel was prepared via the thiol-catechol Michael addition *** starch hydrogel gained shape memory behaviors by coordinate with Fe^(3+)ions at alkaline condition.1H-NMR had been used to character the structure of the starch derivatives and its character *** hydrogel’s modulus had also been measured before and after coordinating with Fe^(3+)ions in linear area and the result showed that both the hydrogel’s storage modulus and loss modulus kept constant in linear area from 0.1 rad/s to 100 rad/s,which demonstrated a good network was formed inside the ***,the shape memory behaviors had been tested by changing the pH value in *** result showed that the hydrogel can keep its temporary shape in high pH condition and recover to its original state after the shaped hydrogel immersed into acidic *** hydrogel might have great application prospects in the field of biomedical and engineering.

关键词： Starch thiol-catechol Michael addition reaction shape memory

A NEW MODEL OF shape memory ALLOYS

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Applied Mathematics and Mechanics(English Edition) 2002年第9期23卷 1009-1015页

作者：朱祎国吕和祥杨大智 Department of Mechanical Engineering Dalian University of TechnologyDalian 116023P R China Department of Material Engineering Dalian University of TechnologyDalian 116023P R China

A new constitutive model of shape memory alloys ( SMAs) based on Tanaka' s martensite fraction exponential expression is produced. this new model can present recoverable shape memory strain during different phase transformation, and reflect the action of martensite reorientation. Also it can overcome the defect of Tanaka' s Model when the SMAs' microstructure is fully martensite. The model is very simple and suitable for using, and the correct behavior of the model is proved by test.

关键词： shape memory constitutive model pseudoelasticity

Facile scalable one-step wet-spinning of surgical sutures with shape memory function and antibacterial activity for wound healing

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Chinese Chemical Letters 2020年第6期31卷 1499-1503页

作者： Xinghan Chen Pengfei Tan Ya Wen Wencheng Zhou Ying Cen Chao You Lin Tan Meng Tian Department of Burns and Plastic Surgery and Neurosurgery Research LaboratoryWest China HospitalSichuan University.Chengdu 610041China College of Biomass Science and Engineering Sichuan UniversityChengdu 610065China Department of Neurosurgery West China HospitalSichuan UniversityChengdu 610041China Key Laboratory of Leather Chemistry and Engineering of Ministry of Education Sichuan UniversityChengdu 610065China

Surgical suture is commonly used in clinic due to its action in accelerating the process of wound ***,difficultly handling in minimally invasive surgery and bacteria-induced infection usually limit its use in a wide range of ***,we report a facile scalable strategy to fabricate surgical sutures with shape memory function and antibacterial activity for wound ***,a shape memory polyurethane(SMPU)with a transition temperature(Ttrans)at 41.3℃was synthesized by adjusting the mole ratio of the hard/soft segment,and then the shape memory surgical sutures containing polyhexamethylene biguanide hydrochloride(PHMB)as a model drug for antibacterial activity were fabricated by a facile scalable one-step wet-spinning approach,in which PHMB was directly dissolved in the coagulation bath that enable its loading into the sutures through the dual diffusion during the phase *** prepared sutures were characterized by their morphology,mechanical properties,shape memory,antibacterial activity,as well as biocompatibility before the wound healing capability was tested in a mouse skin suture-wound *** was demonstrated that the optimized suture is capable of both shape memory function and antibacterial activity,and promote wound healing,suggesting that the facile scalable one-step wet-spinning strategy provides a promising tool to fabricate surgical sutures for wound healing.

关键词： Wet-spinning shape memory Antibacterial activity Surgical suture Wound healing