The crystallization behavior of poly(ethylene glycol) and poly( l ‐lactide) block copolymer: Effects of block length of poly(ethylene glycol) and poly( l ‐lactide)

2019 ◽  
Vol 2 (4) ◽  
Author(s):  
Liying Wang ◽  
Congshu Feng ◽  
Jun Shao ◽  
Gao Li ◽  
Haoqing Hou
Keyword(s):  
Block Copolymer ◽  
Ethylene Glycol ◽  
Crystallization Behavior ◽  
Block Length ◽  
Poly Ethylene Glycol ◽  
Poly Ethylene

PS-b-PEG Block Copolymer for the Compatibility of the Electro Spun Fiber of PS/PEG Blend

2018 ◽  
Vol 14 (5) ◽  
pp. 410-415
Author(s):  
Minghui You ◽  
Qixiang Sun ◽  
Shuo Zhang ◽  
Jingsheng Liu
Keyword(s):  
Phase Separation ◽  
Block Copolymer ◽  
Ethylene Glycol ◽  
Crystallization Behavior ◽  
Core Shell ◽  
Poly Ethylene Glycol ◽  
The Core ◽  
Nano Fiber ◽  
Core Shell Structure ◽  
Poly Ethylene

Background: The electrospining of Poly (styrene)/poly(ethylene glycol) blend and prepared electrospun Poly (styrene)/poly(ethylene glycol) are the composite fibers. The Core-shell structured PS-PEG fibers were founded by polarized optical microscope after electrospinning, meanwhile, the mechanism of structure was also discussed. Methods: The Electro-spinning is a facile method to fabricate polymer fibers. The single-step process to fabricate poly (styrene)(PS)/poly(ethylene glycol)(PEG) polymer nano-fiber meshes had been investigated, respectively. The morphology and crystallization behavior of the blend were observed by polarized optical microscopy. Results: The clear phase separation of PEG encapsulating on the PS fiber surface, and the nano-fiber composed of a core-shell structure, furthermore, the core of PS with the shell of PEG were observed, respectively. To increase the compatibility of the PS/PEG blend, Poly (styrene)(PS)-b-poly(ethylene glycol)(PEG), synthesized via atom transfer radical polymerization (ATRP) was introduced. The addition of the PS-b-PEG block copolymer has no negative effect on the electro-spinning process. Conclusion: When the Block copolymer of PS-b-PEG as a compatibilizer was added into the PS/PEG blend, the homogeneous electrospun fibers without phase separation was obtained. The effect of PS-b-PEG block copolymer on electrospinning of PS/PEG blend was analyzed by evaluating the morphology and crystallization behavior of the electrospun fibers. Under polarized optical microscopy analyses suggest that, it can be found that the phase separation between PS and PEG disappears due to the introduction of the compatibilizer. Meanwhile, the core-shell structure of PEG/PS composite fiber was destroyed and PEG evenly dispersed in PS/PEG blend.

scholarly journals Local Toxicity of Topically Administrated Thermoresponsive Systems: In Vitro Studies with In Vivo Correlation

2018 ◽  
Vol 47 (3) ◽  
pp. 426-432 ◽  
Author(s):  
Sivan Yogev ◽  
Ayelet Shabtay-Orbach ◽  
Abraham Nyska ◽  
Boaz Mizrahi
Keyword(s):  
Block Copolymer ◽  
Ethylene Glycol ◽  
Medical Devices ◽  
Poly Lactic Acid ◽  
Poly Ethylene Glycol ◽  
Thermoresponsive Polymers ◽  
Wide Range ◽  
Poly Ethylene

Thermoresponsive materials have the ability to respond to a small change in temperature—a property that makes them useful in a wide range of applications and medical devices. Although very promising, there is only little conclusive data about the cytotoxicity and tissue toxicity of these materials. This work studied the biocompatibility of three Food and Drug Administration approved thermoresponsive polymers: poly( N-isopropyl acrylamide), poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) tri-block copolymer, and poly(lactic acid-co-glycolic acid) and poly(ethylene glycol) tri-block copolymer. Fibroblast NIH 3T3 and HaCaT keratinocyte cells were used for the cytotoxicity testing and a mouse model for the in vivo evaluation. In vivo results generally showed similar trends as the results seen in vitro, with all tested materials presenting a satisfactory biocompatibility in vivo. pNIPAM, however, showed the highest toxicity both in vitro and in vivo, which was explained by the release of harmful monomers and impurities. More data focusing on the biocompatibility of novel thermoresponsive biomaterials will facilitate the use of existing and future medical devices.

Star-shaped poly(l-lactide)-b-poly(ethylene glycol) with porphyrin core: synthesis, self-assembly, drug-release behavior and singlet oxygen research

2014 ◽  
Vol 38 (8) ◽  
pp. 3569-3578 ◽  
Author(s):  
Xiao-Hui Dai ◽  
Zhi-Ming Wang ◽  
Lu-You Gao ◽  
Jian-Ming Pan ◽  
Xiao-Hong Wang ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Block Copolymer ◽  
Drug Release ◽  
Ethylene Glycol ◽  
Self Assembly ◽  
Release Behavior ◽  
Poly Ethylene Glycol ◽  
Drug Release Behavior ◽  
Porphyrin Core ◽  
Poly Ethylene

pH-induced block copolymer SPPLA-b-PEG with porphyrin core for photodynamic therapy.

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