![]() 24–26įor example, we reported the synthesis of poly(stearyl methacrylate)–poly(benzyl methacrylate) diblock copolymer spheres, worms or vesicles directly in mineral oil via RAFT dispersion polymerization. 22,23 More specifically, various diblock copolymer worm gels have been prepared via PISA syntheses conducted in water, 17 lower alcohols 18,19 and n-alkanes 18 using reversible addition–fragmentation chain transfer (RAFT)-mediated polymerization. 17–21 PISA has proved to be particularly useful for the identification of suitable diblock copolymer compositions and synthesis conditions that enable the formation of purely linear worms in various solvents. Over the past decade or so, polymerization-induced self-assembly (PISA) has become widely recognized as a powerful platform technology for the rational synthesis of block copolymer nano-objects in the form of concentrated colloidal dispersions. 13 Alternatively, Discher and co-workers examined degradable block copolymer worms in the context of drug delivery applications. 8 In the case of aqueous worm gels, this has led to various potential biomedical applications as 3D matrices for cell culture, 9–11 cryopreservation of red blood cells, 12 or the long-term storage of human stem cells. 7 Above a certain critical copolymer concentration, block copolymer worms form free-standing gels. 1,6 Indeed, block copolymer worms have been recently evaluated as thickeners for silicone oils. 1 Their highly anisotropic morphology leads to relatively high solution viscosity. 1–3 Traditionally, they have been prepared using a post-polymerization processing protocol via either a solvent switch 4,5 or by direct dissolution. Introduction Block copolymer worms have been known for several decades. This study informs the use of such block copolymer worms as rheology modifiers for non-polar oils, which is of potential interest for the automotive industry. Complementary shear-induced polarized light imaging (SIPLI) experiments confirmed the formation of aligned linear worms under applied shear between 80 ☌ and 110 ☌, with high-viscosity dispersions of branched worms being obtained at 20–60 ☌ and low-viscosity spheres being produced at 150 ☌. ![]() a Newtonian fluid) on heating up to 150 ☌. ![]() Rheological studies were conducted to characterize the shear rate- and concentration-dependent behaviour caused by this change in copolymer morphology, where the initial shear-thinning worm gels form spheres ( i.e. These worms undergo a thermoreversible worm-to-sphere transition on heating up to 150 ☌. ![]() ![]() Gel permeation chromatography (GPC) studies indicated that almost identical copolymer chains were obtained in all cases, while transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS) studies confirmed that highly anisotropic worms were formed with mean cross-sectional diameters of 11.9–13.1 nm. Free-standing gels were obtained from this polymerization-induced self-assembly (PISA) formulation when targeting PSMA 13–PBzMA 65 dispersions at 5% w/w to 20% w/w copolymer concentration. com,xnxx anime,com,xnxx sister,xnxx site:kingxxx.pro,xnxx teen,xnxx downloader,xnxx china,xnxx blacked,xnxx hot,mom xnxx,xnxx anal,blacked xnxx,https Viral,xnxx.eco,xxxindo,xxmx,pornhub,xvideoXNXX, XXX Sex,XMXX,XBXX,Xxnxx,xxx sex,sex,xnxx memek,Sex Video,Sex Porno,Seks Porno,XXX, xnxx eco, xnxx india, indian porn,xnxx,xnxx.Poly(stearyl methacrylate)–poly(benzyl methacrylate) diblock copolymer worms were synthesized directly in mineral oil via reversible addition–fragmentation chain transfer (RAFT) dispersion polymerization at 90 ☌. ![]()
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