Search results for "Transfer radical polymerization"
showing 6 items of 6 documents
Controlled radical polymerization of alkyl acrylates and styrene using a half-sandwich molybdenum(III) complex containing diazadiene ligands
2003
Abstract The half-sandwich molybdenum(III) complex CpMoCl 2 ( i Pr 2 -dad) ( i Pr 2 -dad= i Pr–NCH–CHN– i Pr) proved to be an effective metal catalyst for the controlled radical polymerization of methyl acrylate, butyl acrylate, and styrene. In conjunction with an alkyl iodide [R–I: CH 3 CH(COOEt)I] as an initiator and in the presence or absence of Al(O– i -Pr) 3 as a co-catalyst, the molybdenum-based system gave polymers with narrow molecular weight distributions. The in situ addition of styrene to a macroinitiator of poly(methylacrylate) afforded an AB-type block copolymer.
Biocompatible Polymers and Processing Techniques in Drug Delivery and Tissue Engineering
2013
On the formation of inclusion complexes at the solid/liquid interface of anchored temperature-responsive PNIPAAM diblock copolymers with γ-cyclodextr…
2017
The thermal responsive behavior of adsorbed layers of diblock copolymers of poly(N-isopropylacrylamide) (PNIPAAM) and poly((3-acrylamidopropyl)trimethylammonium chloride) (PAMPTMA(+)) with γ-cyclodextrin (γ-CD) at the solid/liquid interface has been investigated using three in situ techniques: null ellipsometry, quartz–crystal microbalance with dissipation monitoring, and neutron reflectometry. The measurements provided information about the adsorbed amounts, the layer thickness, hydration and viscoelastic properties, and the interfacial structure and composition. The copolymers adsorb to silica with the cationic PAMPTMA(+) blocks sitting as anchors in a flat conformation and the PNIPAAM ch…
Recent advances in smart biotechnology: Hydrogels and nanocarriers for tailored bioactive molecules depot
2017
Over the past ten years, the global biopharmaceutical market has remarkably grown, with ten over the top twenty worldwide high performance medical treatment sales being biologics. Thus, biotech R&D (research and development) sector is becoming a key leading branch, with expanding revenues. Biotechnology offers considerable advantages compared to traditional therapeutic approaches, such as reducing side effects, specific treatments, higher patient compliance and therefore more effective treatments leading to lower healthcare costs. Within this sector, smart nanotechnology and colloidal self-assembling systems represent pivotal tools able to modulate the delivery of therapeutics. A comprehens…
Half-sandwich Mo(III) complexes with asymmetric diazadiene ligands
2006
The asymmetric 1,4-diazadiene ligands R ∗ N CHCH NR ∗ [R ∗ = ( S )-CH(CH 3 )Ph], R 2 ∗ dad , and 2,2′-bis(4-ethyloxazoline), as-ox, have been used to generate half-sandwich Mo III derivatives by addition to Cp 2 Mo 2 Cl 4 . Ligand R 2 ∗ dad affords a mononuclear, paramagnetic 17-electron product, CpMoCl 2 ( R 2 ∗ dad ) , whereas as-ox leads to the isolation of a dinuclear compound where only one molecule of ligand has been added per two Mo atoms, Cp 2 Mo 2 Cl 4 (as-ox). In the presence of free as-ox, this compound coexists with the paramagnetic mononuclear complex in solution. Both products are capable of controlling the radical polymerization of styrene under typical atom transfer radical…
Study of Atrp Process for the Grafting of Vinyl Monomers on PVC and PVDF
2014
STUDY OF ATRP PROCESS FOR THE GRAFTING OF VINYL MONOMERS ON PVC AND PVDF Sonia Lanzalaco, Onofrio Scialdone, Alessandro Galia, Rosalia Mauro, Flavia Lazzano Dipartimento di Ingegneria Chimica, Gestionale, Informatica, Meccanica, Viale delle Scienze, Palermo e-mail: sonia.lanzalaco@unipa.it ATRP (atom transfer radical polymerization) has been recently used to prepare graft copolymers with regularly-spaced polymer chains from polymeric macroinitiators that have pendant chemical groups containing radically transferable halogen atoms [1]. The halogen atom serves as initiation site for the polymerization of side chains. Furthermore, Matyjaszewsky and Gennaro showed that an externally applied ele…