Acrylonitrile-methyl Methacrylate Copolymer Films Containing Microencapsulated n-Octadecane

Acryionitrilv-methyi mcthacrylate copolymer was synthesized in aqueous solution by Redox. The copolymer was mixed with 10 - 40 wt% of microencapsulated n-octadecane （MieroPCMs） in water. Copolymer films containing Mi- eroPCMs were cast at room temperature in N, N- imethyiformamide solution. The copolymer of acrylonitrile-methyl methacrylate and the copolymer films containing MicroPC- Ms were characterized by using Fourier Transform Infrared Spectroscopy （FTIR）, Differential Scanning Calorimetry （DSC）, Thermosravimetrlc Analyzer （TG）, X-ray Diffraction （XRD） and Scanning Electron Microscopy （SEM）, etc. The mierocapsules in the films are evenly distributed in the copolymer matrix. The heat-absorbing temperatures and heat-evolving temperatures of the films are almost the same as that of the MieroPCMs, respectively, and fluctuate in a slight range. In addition, the enthalpy efficiency of MieroPCMs rises with the contents of MicroPCMs increasing. The crystallirdty of the film increases with the contents of MicroPOMs increasing.

STUDY ON MICROSTRUCTURE AND REACTIVITY RATIOS OF ISOPRENE-METHYL METHACRYLATE COPOLYMERS BY 250 MHz ~1H-NMR

The composition and the microstructures of isoprene-methyl methacrylate copolymers havebeen quantitatively studied by 250 MHz 1H-NMR spectra. Applying two lanthanide shiftreagents, by examining the separation of resonance peaks of the 1,4-isoprene olefin proton,I-centred triad distributions, and even I-cectred pentad fractions are measured. It is con-firmed that there is a penultimate of effect in this free radical copolymerization and the reac-tivity ratios established corresponding to Second-order Markov chain model are r11=0.48,rMI=0.86, rMM=0.51 and rIM=0.43, respectively. The observed I-centred pentad fraetions andM-centred triad distributions agree with the above results.

COPOLYMERIZATION PROCESS OF TRIPHENYLMETHYL METHACRYLATE AND MMA WITH CHIRAL ANIONIC COMPLEX INITIATOR

The copolymerization process of triphenylmethyl methacrylate (TrMA) and methylmethacrylate (MMA) using chiral anionic complex initiator (-) SP-FlLi (Scheme 1) has beenstudied in toluene and THF, respectively. The copolymer obtained in toluene possessed muchhigher specific rotation than that in THF. These copolymers have shown a tendency to a random and a like alternating structure, respectively.

THE SYNTHESIS OF NEW POLED CROSSLINKED POLYMETHACRYLATES AND THEIR SECOND ORDER NONLINEAR OPTICAL PROPERTIES

Films were prepared from mixtures of copolymers of 4-nitro-4'-[N-methylacryloyloxyethyl, N'-ethyl] amino azobenzene with glycidyl methacrylate (chromophore content: 6 mol%) and copolymers containing anhydride units, which was obtained by the reaction of 4-nitro-4'-[N-hydroxyethyl, N'-ethyl] amino azobenzene with polymethacryloyl chloride (chromophore content: 25 mol %). During thermal poling process the anhydride reacts with the epoxy group and the resulting crosslinked network structure will stabilize the second harmonic generation in the poled film. The second harmonic generation of the poled film shows a maximum with the variation of composition this is presumed to be due to the effects of the increasing of concentration, orientation order as well as orientation stability of chromophore groups during crosslinking.

INFLUENCES OF ACID POST-TREATMENT ON THE MORPHOLOGY OF SOAP-FREE P(MMA-EA-MAA)PARTICLES PREPARED BY SEEDED EMULSION POLYMERIZATION

Soap-free poly（methyl methacrylate-ethyl acrylate-methacrylic acid） latex particles with narrow size distribution were synthesized by seeded emulsion polymerization, and the porous particles were created by a stepwise alkali/acid treatment method. Effects of acid treatment conditions on the particle morphology were investigated. Results show that one to three pores were formed inside most of particles after post-treatment. At pH 7.0, when the treatment temperature was lower than 70℃, the size of particles and the volume of pores remained almost unchanged, and these two values increased significantly when the temperature was higher than 70℃. Both the particle size and the pore volume decreased with the increase of initial pH value and treatment time in the acid treatment. As the pH was below 4.0 and the treatment time was longer than 180 min, the particles shrunk in size.

Miniemulsion Cross-linking:A Convenient Route to Hollow Polymeric Nanocapsule with a Liquid Core

Miniemulsion stabilized by poly（2-（dimethylamino） ethyl methacrylate）-block-poly（butyl methylacrylate）（PDMAEMA-b-PBMA） diblock copolymers has been used as liquid templates for the synthesis of polymer nanocapsules via quaternization cross-linking of PDMAEMA segments of the copolymer by 1,2-bis（2-iodoethoxy）ethane（BIEE） crosslinkers. PDMAEMA-b-PBMAs here as a stabilizer in miniemulsion with different molecular weights led to a size variation in diameters of nanocapsules, demonstrating the capsules have potential design capability of this technique. The solution behavior of the capsules has been also investigated in this paper.