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The soap-free emulsion polymerization of methyl methacrylate (MMA) was carried out with varying amount of methanol in the aqueous medium. As methanol content increased, the phase of polymerization mixture (methanol/water/monomer) changed from heterogeneous to homogeneous state and the transition occurred at 30 wt% methanol. In order to identify the mechanism of the polymerization in heterogeneous...
A series of soluble conductive vinyl copolymers containing a hole-transporting N-(4-methoxyphenyl)-N-phenylnaphthalen-1-amine (MeONPA) moiety and an electron-transporting/hole-blocking 2,5-diphenyl-1,3,4-oxadiazole (OXA) moiety at different composition ratios were synthesized and characterized. The copolymers were applied as the hole-transporting layer (HTL) for a series of heterojunction Organic...
The targeted molecular weight poly (methyl methacrylate) [PMMA] latex was successfully prepared in the presence of 4,4-azobis(4-cyanopentanoic acid) (ACPA) and various surfactants using the reversible iodine transfer polymerization (RITP)-emulsion polymerization at 85°C for 7h in the absence of light. The properties of PMMA particles upon the various ratios of ACPA to iodine within the concentration...
The dispersion polymerization of methyl methacrylate (MMA) has been carried out using polystyrene-block-poly(4-vinylpyridine) copolymer [P(S-b-4VP)], which was prepared by a reversible addition–fragmentation chain transfer (RAFT) method, as a steric stabilizer in an alcohol media. The stable polymer particles were obtained when the block copolymer concentrations increased from 1 to 10wt% relative...
Monodisperse poly(methylmethacrylate) microspheres having a diameter of 2.6μm and a molecular weight of 102,277g/mol with 5.3% of the C v (the coefficient of variation) were synthesized by the dispersion polymerization using hydrophilic polyvinylalcohol (PVA) in methanol/water mixture media. Then, the structural verification of the synthesized materials is confirmed by using 1 H NMR...
The cross-type vinylurethane macromonomers (C-VUMs) were successfully synthesized using trimethylolpropane (TMP) as a cross-agent, and applied to the dispersion polymerization of styrene in ethanol. The existence and the structural identification of the reactants and the products were verified using the FT-IR and 1 H NMR spectra. The molecular weight of C-VUM increased, but the polydispersity...
Bifunctional polyurethane-based macromonomers (BPUM) were synthesized from various molecular weights of polyethylene glycol (PEG) and hexamethylene diisocyanate (HDI) with different end group functionalities. The synthesized BPUMs were applied to the dispersion polymerization of styrene in ethanol. Structures of various macromonomers and PS particles were investigated using 1 H NMR. Molecular...
Mechanical properties and complex melt viscosity of unfilled and the calcite (calcium carbonate: CaCO 3 ) filled high density polyethylene (HDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE) composites using dumbbell bar and film specimens are studied. In addition, the formation of air holes between calcium carbonate and the resin matrix was investigated from...
The effect of chain end groups on the thermodynamics of polymer blends is investigated by the collection of cloud point curves for low molecular weight blends of poly(isoprene) (PIP) with three different α,ω-functionally-terminated poly(dimethyl siloxane) (PDMS) materials: α,ω-trimethylsilyl PDMS (PDMS–CH 3 ), α,ω-propylamino PDMS (PDMS–NH 2 ) and α,ω-propylcarboxy PDMS (PDMS–COOH)...
Benzoxazine resins and poly(ε-caprolactone) (PCL) are melt blended and the properties of the blends in the range of 0–15wt.% of PCL are studied by dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA). The Tgs of the benzoxazine blends in the presence of PCL are found to be slightly lower than that of neat polybenzoxazine resin. The blends show improved mechanical properties, including...
Polymer nanocomposites based on a synthetic layered silicate and polyamide-12 (PA-12) are prepared by injection molding to study their morphology, and the influence of nanofiller particles on local deformation processes. One of the most striking results from morphological studies by transmission electron microscopy is that although the layered silicates, locally stacked in the PA-12 matrix, are arranged...
Several poly(amic diisopropyl ester-alt-imide)s have been synthesized, which are a new type of polyimide precursors. The precursors consist of amic ester and imide units alternatively on the backbone, so that they are hydrolytically stable as well as low shrinkable through thermal imidization. These precursors have an easy processability because of their good solubility in common solvents that are...
Thermal and mechanical properties of ethylene/α-olefin copolymers (LLDPE) produced over bis(2-methyl indenyl)zirconium dichloride((2-MeInd)2ZrCl2) were compared with those of LLDPEs synthesized with a conventional heterogeneous Ziegler–Natta (Z–N) catalyst, titanium tetrachloride supported on magnesium diethoxide with diisobutyl phthalate as an internal donor(Mg(OEt)2/DIBP/TiCl4). DSC thermogram of...
A series of all sol-gel organic-inorganic nonlinear optical materials based on the prepolymers of melamines and an alkoxysilane dye (ASD) were investigated. The NLO-active ASD containing nitroazobenzene was incorporated into the melamine matrices with different weight ratios. This all sol-gel type is shown to have the advantages of simultaneous polymerizations, and better compatibility between two...
Poly(2-trimethylsilyl-2-propyl methacrylate-co-γ-butyrolactone-2-yl methacrylate) was synthesized and evaluated as a chemically amplified resist for ArF lithography. The polymer has excellent transmittance at 248nm and also has a good transmittance at 193nm. In addition, the polymer possesses good thermal stability up to 200°C, whereas in the presence of an acid the cleavage of the 2-trimethylsilyl-2-propyl...
The same molecular weight distribution is always attained for both dead and living polymers when the living polymerization is carried out in a continuously stirred tank reactor, which cannot be achieved in a batch reactor. The average molecular weight and the yield are completely controllable to any desired values. However, the polydispersity index is determined by the average molecular weight only,...
The healing process of fractured polymers is analysed on the basis of the minor chain model. The healing at the interface by interdiffusion is described in terms of the concentration of minor chains. Chain scission would occur at the surfaces of fractured polymers and the resulting minor chains play an important role in the healing process. The localized minor chains at the interface dominate over...
Polyurethane (PU) ionomer acrylates and non-ionomer acrylates were synthesized from poly(propylene glycol)((PPG), isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA), 2-hydroxyethylacrylate (HEA), and N-vinylpyrrolidone (NVP), tripropyleneglycol triacrylate (TPGDA), trimethylolpropane triacrylate (TMPTA), and were characterized in terms of water swell, mechanical, and dynamic mechanical...
The re-entry rate in emulsion polymerization is reformulated by taking into account both the enter and exit processes together. The role that the free radicals play in these rate processes is used directly in the formulation. Based on the formulation, expressions are derived for the re-entry and exit rate coefficients, the average number of free radicals in a polymer particle, and the total free...
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