- Designing semiencapsulation based covalently self-healable poly(methyl methacrylate) composites by Atom Transfer Radical Polymerization
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Self-healable poly(methyl methacrylate) (PMMA) composites were fabricated with embedded glycidyl methacrylate (GMA) encapsulated poly(melamine-formaldehyde) microcapsules. The matrix polymers were synthesized via Atom Transfer Radical Polymerization using two different initiators; one linear and another hexafunctional. As the so prepared polymer matrix retains living characteristics, it can initiate a healing reaction when the encapsulated monomer reaches the matrix due to formation or extension of a crack and thus healing the system covalently. The effect of number of initiating functionality on healing characteristic was studied using both linear and 6-armed star PMMA having same targeted molecular weight. Both the systems were able to restore 100% original fracture toughness after healing. However, the polymer matrix prepared by hexafunctional initiator restored the fracture toughness much faster than that of the linear polymer matrix.
- Saikia, Bhaskar Jyoti,Dolui, Swapan Kumar
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- Novel fluorinated block copolymer architectures fuelled by atom transfer radical polymerization
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Block copolymers based on poly(pentafluorostyrene), PFS, in various numbers and of different lengths, and polystyrene are prepared by atom transfer radical polymerization (ATRP). Di- and triblock copolymers with varying amounts of PFS were synthesized employing either 1-phenylethylbromide or 1,4-dibromoxylene as initiators for ATRP. Diverse bromo(ester) (macro)initiators were also devised and involved in the formulation of fluorinated pentablock as well as amphiphilic triblock copolymers with a central polyether segment. Amphiphilic star-shaped fluoropolymers, hydrophobic fluorinated nanoparticles, or segmented fluorinated star-shaped block copolymers are further designed by use of different multifunctional initiators. The composition of the novel materials with PFS is determined by combination of SEC and 1H NMR. Glass transition temperatures and thermal stabilities of the hydrophobic star-shaped PFSs on a six arm dipentaerythritol core are investigated in a wide range of molecular masses and further discussed.
- Jankova, Katja,Hvilsted, S?ren
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- ANTIVIRAL POLYMERS
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The present invention relates to polymer compounds that have antiviral activity. The compounds have the structural Formula I defined herein. The present invention also relates to processes for the preparation of these compounds, to compositions comprising
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Paragraph 00160
(2021/11/26)
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- Tumor active targeting star-shaped amphiphilic polymer micelle nano-drug and preparation method thereof
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The invention discloses a star-shaped amphiphilic polymer and a preparation method thereof and a nano drug with a constructed micelle of the star-shaped amphiphilic polymer as a carrier. The star-shaped amphiphilic polymer is prepared by adopting polyhydric alcohol as an inner core, initiating the polymerization of glycidyl methacrylate (GMA) through activation, and then utilizing an active epoxyfunctional group to react with an amine-terminated hydrophobic chain segment (A-NH2) and targeting group (B) modified polyethylene glycol (B-PEG-NH2) separately. Polylactic acid (PLA-NH2) or polycaprolactone (PCL-NH2) is preferably selected as the hydrophobic chain segment, and anisamide (Anis) or phenylboronic acid (PBA) is preferably selected as the targeting group. According to the star-shapedamphiphilic polymer prepared by the method, the raw materials are cheap and easy to obtain, the biocompatibility is great, and the preparation process is relatively simple and easy. At the same time,the nano drug with the constructed micelle of the star-shaped amphiphilic polymer as the carrier can have long circulation in the blood and an active targeting function, and therefore the nano drug has a good anti-tumor effect.
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Paragraph 0059-0061; 0065-0067
(2020/07/24)
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- The behaviour of honeycomb film formation from star polymers with various fluorine content
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A series of poly((1H,1H-pentafluoropropyl acrylate)-ran-(methyl methacrylate)) (poly(PFPA-ran-MMA)) star polymers with varying fluorine content were prepared via the core-first approach using atom-transfer radical polymerisation (ATRP). Subsequently, the star polymers were used to prepare honeycomb films on both planar and non-planar surfaces via the 'Breath Figures' technique using a static casting method. The fluorine content of the star polymers was observed to influence the morphology of the honeycomb structures and the formation of non-cracking honeycomb films on non-planar surfaces. Moreover, the average pore diameter of the honeycomb films was found to decrease with increasing fluorine content, as well as increasing polymer concentration in the casting solution or decreasing humidity during casting. The increasing fluorine content of the star polymers was also found to result in a decrease in their glass transition temperatures and Young's modulus values.
- Zhang, Zhou,Hughes, Timothy C.,Gurr, Paul A.,Blencowe, Anton,Uddin, Hemayet,Hao, Xiaojuan,Qiao, Greg G.
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p. 4446 - 4454
(2013/08/23)
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