Additive-free synthesis of poly(n-vinyl pyrrolidone) and poly(n-isopropylacrylamide) nanogels with controlled sizes
نویسندگان
چکیده
An easy method is proposed to prepare poly(vinyl pyrrolidone) (PVP) and poly(N-isopropylacrylamide) (PNiPAAm) nanogels with sizes less than 100 nm. The underlying principle dilute polymer solutions in acetone/water mixtures where acetone acts break tridimensional structure of water hence disrupting the H-bonds bridging coils causing separation shrinkage their sizes. Irradiation these by gamma-rays directly leads formation intramolecular crosslinks within resulting smaller precursor coils. While average size PVP irradiated only 236 nm, they were reduced about 44 nm when irradiation was carried out at near theta compositions. PNiPAAm also synthesized irradiating solutions. Multimodal coil distribution converted into monomodal 70 low dispersity addition acetone. such yielded 50 size. Stability followed for 1 year not showing any changes or distributions. Nanogels characterized dynamic light scattering, scanning electron microscopy, atomic force microscopy techniques.
منابع مشابه
Polyn ô mes
1.1 Définitions élémentaires Définition 1. Soit P ∈ k[X ] et a ∈ k. On dit que a est une racine de P si P (a) = 0, ou de manière équivalente si X − a divise P . On appelle multiplicité de a le plus grand entier μ tel que (X − a) divise P . Proposition 1. Si P ∈ k[X ] admet a1, . . . , al pour racines, de multiplicités respectives μ1, . . . , μl, alors il existe Q ∈ k[X ] tel que P = Q∏(X − ai)i...
متن کاملPoly(vinyl pyrrolidone)-capped five-fold twinned gold particles with sizes from nanometres to micrometres.
Poly(vinyl pyrrolidone)-capped multiple twinned gold (Au) particles with decahedral shape have been synthesized by a simple and convenient solvothermal wet chemical method. In the process, hydrogen tetrachloroauric acid (HAuCl(4).3H(2)O) was reduced by ethylene glycol (EG) to form the multiple twinned Au nanocrystals in the presence of poly(vinyl pyrrolidone) (PVP) molecules at 200 degrees C un...
متن کاملsingle-step synthesis of multi-component spirobarbiturates using ionic liquids and synthesis of substituted pyridine filled with catalysts supported on solid substrate
in this thesis, a better reaction conditions for the synthesis of spirobarbiturates catalyzed by task-specific ionic liquid (2-hydroxy-n-(2-hydroxyethyl)-n,n-dimethylethanaminium formate), calcium hypochlorite ca(ocl)2 or n-bromosuccinimide (nbs) in the presence of water at room temperature by ultrasonic technique is provided. the design and synthesis of spirocycles is a challenging task becaus...
15 صفحه اولSynthesis and applications of polystyrene-block- poly(N-vinyl-2-pyrrolidone) copolymers
This work describes the synthesis and applications of amphiphilic polystyrene-block-poly(N-vinyl-2-pyrrolidone) (PS-b-PVP) copolymers as a silver and silica nanoparticle surface modification agent. The synthesis of PS-b-PVP was carried out using controlled/living radical polymerization techniques. The synthesis of the block copolymers was confirmed by gel permeation chromatography and hydrogen ...
متن کاملSynthesis and Photopolymerization of Tween 20 Methacrylate/N-vinyl-2-Pyrrolidone Blends
a r t i c l e i n f o Poly(oxyethylene 20 sorbitan) monolaurate (Tween® 20) methacrylates were synthesized by coupling methacryloyl chloride (MeOCl) to Tween 20 in the presence of 4-(N,N-dimethylamino) pyridine, using THF as a solvent, in order to investigate their suitability as precursors for photopolymerizable hydrogels in tissue engineering applications. The degree of substitution could be ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Turkish Journal of Chemistry
سال: 2023
ISSN: ['1300-0527', '1303-6130']
DOI: https://doi.org/10.55730/1300-0527.3545