Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

2 International Letters of Chemistry, Physics and Astronomy

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Di-stimuli Responsive poly(N-Isopropylacrylamide-co-Diethylaminoethylmethacrylate) Copolymer: Synthesis, Characterization and Investigation of Aqueous Dispersion Properties

100%

Ashaduzzaman M. , Islam Shahidul M.

International Letters of Chemistry, Physics and Astronomy

2014

tom Vol. 20, iss. 2

136--144

We report on the synthesis, characterization and aqueous dispersion properties of well-defined double hydrophilic copolymer with pH- and thermo-responsive segments via atom transfer radical polymerization (ATRP). Poly(N-isopropylacrylamide-co-Diethylaminoethylmeth-acrylate), P(NIPAAm-co-DEAEMA), was prepared by ATRP using methyl-4-bromomethyl benzoate initiator. The product was characterized by proton-nuclear magnetic resonance (1H NMR) and attenuated total reflectance infrared (ATR-IR) spectroscopy. The multi-responsive switching between unimer and two types of micellar aggregates were characterized by temperature-dependent dynamic light scattering (DLS). Self-assembles into two types spherical aggregates in 1 mg/mL (0.0315 mM) aqueous solution, depending on solution pH and temperatures were widely investigated. The result shows two types of aggregate with large (280 nm) aggregate and variable sizes of small (17 nm, 25 nm, 45 nm) aggregates depending on temperature ranges from 26 to 40 °C at pH 4.

Surface initiated ATRP: Synthesis and Characterization of Functional Polymers Grafted on Modified Cellulose Beads

80%

Ashaduzzaman M. , Ishikura K. , Sakata M. , Kunitake M.

tom Vol. 8, iss. 3

243-248

Atom transfer radical polymerization (ATRP) was employed to synthesize novel polymer particles. The surface of porous polymeric cellulose beads was modified by sodium hydroxide, 2-chloromethyloxirane, ethylenediamine and 2-bromo-2-methylpropionyl bromide successively in order to activate the beads surface so that it can play an important role as an initiator for ATRP reaction. ATRP on the modified cellulose beads surface was carried out with styrene and sodium p-styrenesulphonate monomers in the presence of non aqueous and aqueous phases respectively. The polymer products on the substrate surface were characterized by elemental analysis (EA), attenuated total reflectance-infrared (ATR-IR) spectroscopy and carbon13 - nuclear magnetic resonance (13C-NMR).