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A Disulfide-Based Poly(ether-b-amide)Copolymer with Rapid Self-healing Ability under Moderate

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Chinese Journal of Chemistry 2024年第9期42卷 943-950页

作者： Weijan Lu ping Zhu Ying Zhao Dujin Wang Xia Dong Institute of Chemistry Chinese Academy of SciencesBeijing 100190China Schoolof Chemical Sciences University of Chinese Academy of SciencesBejing 100049China

Comprehensive Summary A disulfide-based poly(ether-b-amide)copolymer with rapid self-healing capability under moderate conditions was synthesized from 4,4’-dithiodibutyric acid(DTDBA),isophorondiamine(IPDA)and poly(tetramethylene oxide)(PTMO)based on a two-step method.The incorporation of IPDA with asymmetric structure and substantial steric hindrance not only effectively decreased the number of regular H-bonds,but also inhibited the crystallization of polyamide segments,imparting the synthesized poly(ether-b-amide)copolymer with an amorphous structural feature.Based on the coordination of segmental diffusion and recombination of disulfide bonds and hydrogen bonds,the scratches and damaged mechanical properties of PEBADS-I611 could be completely self-healed after healing at 40°C for only 11 min and 3 h,respectively.

关键词： Poly(ether-b-amide)copolymer Disulfide bonds Hydrogen bonds Polycondensation smart polymers Self-healing

smart polymers and Coatings Obtained by Ionizing Radiation: Synthesis and Biomedical Applications

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Open Journal of Polymer Chemistry 2015年第3期5卷 17-33页

作者： H.Iván Meléndez-Ortiz Gustavo H.C.Varca Ademar B.Lugao Emilio Bucio Departamento de Materiales Avanzados Centro de Investigación en Química Aplicada Saltillo México Instituto de Pesquisas Energéticas e Nucleares—IPEN-CNEN/SP Cidade Universitária Sao Paulo Brasil Departamento de Química de Radiaciones y Radioquímica Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México Circuito Exterior Ciudad Universitaria México DF México

Gamma radiation has been shown particularly useful for the functionalization of surfaces with stimuli-responsive polymers. This method involves the formation of active sites (free radicals) onto the polymeric backbone as a result of the exposition to high-energy radiation, in which a proper microenvironment for the reaction among monomer and/or polymer and the active sites takes place, thus leading to propagation which forms side chain grafts. The modification of polymers using high-energy irradiation may be performed by the following methods: direct or simultaneous, pre-irradiation oxidative and pre-irradiation. The most frequent ones correspond to the pre-irradiation oxidative method and the direct one. Radiation-grafting has many advantages over conventional methods considering that it does not require catalyst nor additives to initiate the reaction, and in general, no changes on the mechanical properties with respect to the pristine polymeric matrix are observed. This chapter focused on the synthesis of smart polymers and coatings obtained by the use of gamma radiation. In addition, diverse applications of these materials in the biomedical field are also reported.

关键词： smart polymers pH Responsive LCST Biomedical Applications Radiation-Grafting

polymers in Drug Delivery

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Journal of Biosciences and Medicines 2016年第1期4卷 69-84页

作者： Apurva Srivastava Tejaswita Yadav Soumya Sharma Anjali Nayak Akanksha Akanksha Kumari Nidhi Mishra Department of Applied Science Indian Institute of Information Technology Deoghat Jhalwa Allahabad India

polymers are being used extensively in drug delivery due to their surface and bulk properties. They are being used in drug formulations and in drug delivery devices. These drug delivery devices may be in the form of implants for controlled drug delivery. polymers used in colloidal drug carrier systems, consisting of small particles, show great advantage in drug delivery systems because of optimized drug loading and releasing property. Polymeric nano particulate systems are available in wide variety and have established chemistry. Non toxic, biodegradable and biocompatible polymers are available. Some nano particulate polymeric systems possess ability to cross blood brain barrier. They offer protection against chemical degradation. smart polymers are responsive to atmospheric stimulus like change in temperature;pressure, pH etc. thus are extremely beneficial for targeted drug delivery. Some polymeric systems conjugated with antibodies/specific biomarkers help in detecting molecular targets specifically in cancers. Surface coating with thiolated PEG, Silica-PEG improves water solubility and photo stability. Surface modification of drug carriers e.g. attachment with PEG or dextran to the lipid bilayer increases their blood circulation time. Polymer drug conjugates such as Zoladex, Lupron Depot, On Caspar PEG intron are used in treatment of prostate cancer and lymphoblastic leukemia. Polymeric Drug Delivery systems are being utilized for controlled drug delivery assuring patient compliance.

关键词： Polymeric Drug Delivery Biocompatible polymers smart polymers Polymeric Implants Polymeric Drug Formulations

Synthesis of Temperature- and pH-Sensitive Graft Copolymer Containing 2-(Diethylamino)ethyl Methacrylate and N-Vinylcaprolactam onto Silicone Rubber

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Open Journal of Polymer Chemistry 2016年第3期6卷 15-26页

作者： Alejandra Jiménez-Morales Alejandro Ramos-Ballesteros Emilio Bucio Departamento de Química de Radiaciones y Radioquímica Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México Circuito Exterior Ciudad Universitaria México DF México

Silicone rubber films were modified by the consecutive grafting of 2-(diethylamino)ethyl methacrylate (DEAEMA) and N-vinylcaprolactam (NVCL) using direct method on two steps with gamma-rays. The effect of absorbed dose and monomer concentration on grafting degree was determined. The grafted samples were verified by FTIR-ATR spectroscopy and swelling;thermal properties were analyzed by DSC and TGA. The stimuli-responsive behavior was studied by swelling and/or DSC. Thermo- and pH-sensitive films of (PP-g-DEAEMA)-g-NVCL presented a pH critical at 3.2 and LCST around 63.5℃.

关键词： Radiation-Grafting smart polymers 2-(Diethylamino)ethyl Methacrylate N-Vinylcaprolactam

Simplifying Molecular Complexity for the Synthesis of Polymer Materials

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Simplifying Molecular Complexity for the Synthesis of Polyme...