Hybrid Organic–Inorganic Copolymers from Oxohydroxoorganotin Dimethacrylate and Methyl Methacrylate

Organic–inorganic polymeric derivatives constituted by methyl methacrylate co-units and an oxohydroxobutyltin macrocation difunctionalized with methacrylate counterions have been prepared by radical polymerization in solution. The reaction affords soluble products, indicative of a substantial absence of cross-linking originated by the difunctional macrocationic comonomer, when the molar excess of methyl methacrylate is high. The organic–inorganic hybrid products obtained have been characterized by various techniques, thus allowing us to propose a mechanism for their formation which implies a role as chain termination agent for the macrocationic monomer.     

Homo- and copolymerization of (Methacryloyl ethenedioxy)pentachlorocyclotriphosphazene

A new organofunctional cyclophosphazene monomer, (Methacryloyl ethylenedioxy) pentachlorocyclotriphosphazene (N₃P₃Cl₅OCH₂CH₂OC(O)C(CH₃)=CH₂; I), has been prepared from 2-hydroxyethyl methacrylate and hexachlorocyclotriphosphazene. Radical-initiated homopolymerization of I and copolymerization of I with methyl methacrylate proceeds readily. The new flame-retardant polymers have been characterized by elemental analysis, NMR spectroscopy, gel permeation chromatography, membrane osmometry, and TGA. Reactivity ratios and Alfrey-Price parameters for the methyl methacrylate copolymerization show a significant effect of the phosphazene on the olefin reactivity.     

Electroinitiated polymerization of methyl methacrylate in two phase media

The electroinitiated polymerization of methyl methacrylate has been carried out in an intimately mixed two phase medium consisting of a polar solvent containing some added electrolytes and a non-polar phase containing the monomer. Formamide has been used as the solvent for the polar phase and methyl methacrylate either alone or in solution in benzene or toluene has been used as the non-polar phase. Ferric salts are found to catalyse the electropolymerization process; using ferric sulphate as the electrolyte, polymers having molecular weights in the range, 1–2×10⁶ have been obtained, with the highestR _p of 7.3% per hour and the highest polymerization efficiency of 30.37 mol F^–1. A radical mechanism is suggested for the process based on the experimental results.     

Synthesis of defined polyhedral oligosilsesquioxane‐containing diblock and triblock methacrylate copolymers by atom transfer radical polymerization

Defined diblock and triblock copolymers composed of methyl methacrylate‐co‐glycidyl methacrylate block and 3‐{3,5,7,9,11,13,15‐hepta(2‐methylpropyl)‐pentacyclo[9.5.1.1^3,9.1^5,15.1^7,13]‐octasiloxan‐1‐yl}propyl methacrylate block(s), i.e., P(MMA‐co‐GMA)‐b‐PiBuPOSSMA and PiBuPOSSMA‐b‐P(MMA‐co‐GMA)‐b‐PiBuPOSSMA, were synthesized by atom transfer radical polymerization (ATRP). First, monofunctional and bifunctional P(MMA‐co‐GMA) copolymers were synthesized by ATRP. Subsequently, these copolymers were successfully used as macroinitiators for ATRP of POSS‐containing methacrylate monomer. The process showed high initiation efficiency of macroinitiators and led to products with low dispersity. The synthesized block copolymers were characterized by size exclusion chromatography, ¹H‐NMR spectroscopy and their glass transition temperatures were determined by differential scanning calorimetry. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis of cassava starch‐g‐poly(methyl methacrylate) copolymers with benzoyl peroxide as an initiator

Graft copolymers of cassava starch and methyl methacrylate (MMA) were synthesized by free‐radical polymerization with benzoyl peroxide (BPO) as an initiator in an aqueous medium at 80°C. The formation of graft copolymers was confirmed by analysis of the obtained products with Fourier transform infrared spectroscopy and scanning electron microscopy. The effects of the amount of cassava starch, the amount of MMA monomer, the amount of BPO, and the reaction time on the grafting characteristics were studied. The optimum condition for grafting were obtained when 5 g of cassava starch, 5 g of MMA, 0.1 g of BPO, and a reaction time of 3 h were used. These condition provided a graft copolymer with 25.00% add‐on, 81.40% monomer conversion, 54.30% homopoly(methyl methacrylate) formed, 45.70% grafting efficiency, 37.20% grafting ratio, and 95.54% yield. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4083–4089, 2006     

Poly(methyl methacrylate)/POSS hybrid networks by type II photoinitiated free radical polymerization

A new strategy for organic–inorganic hybrid networks is presented through in‐situ Type II photoinitiated polymerization of methyl methacrylate with diethanolamino‐functionalized polyhedral oligomeric silsesquioxanes (POSS‐DEA). The diethanolamino groups are simply incorporated onto POSS nanoparticles by nucleophilic ring‐opening reaction of commercially available epoxycyclohexyl POSS and diethanol amine. The photoinitiated polymerization of methyl methacrylate in the presence of benzophenone as photosensitizer and POSS‐DEA as hydrogen donor leads to poly(methyl methacrylate) (PMMA)/POSS hybrid networks under UV light irradiation. The morphology and thermal properties of hybrid networks are investigated by using Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and transmission electron microscopy. The morphology results confirm that POSS cages are homogeneously distributed in PMMA matrix at the molecular levels, whereas the thermal analyses shows that the obtained hybrid networks have higher glass transition temperatures and better thermal stabilities compared to parent PMMA homopolymer. POLYM. COMPOS., 35:1614–1620, 2014. © 2013 Society of Plastics Engineers     

Stereoregular poly(alkyl methacrylate)s: polymer-polymer and copolymer-polymer blends

Amorphous blends of isotactic and syndiotactic poly(methyl methacrylate) were found to be compatible. To evaluate the interaction between these tactic polymers, random copolymers of isotactic poly(methyl/ethyl methacrylate) were blended with syndiotactic poly(methyl methacrylate). Only the copolymers with an ethyl methacrylate content below 45% were compatible with syndiotactic poly(methyl methacrylate). Using a Flory-Huggins type treatment of copolymer mixtures, the segmental interaction parameters for poly(methyl methacrylate) with poly(ethyl methacrylate) and for isotactic with syndiotactic poly(methyl methacrylate) were calculated. The interaction parameter for the tactic poly(methyl methacrylate) pair was found to be small and negative.     

Causes of secondary gel particles in production of polyacrylonitrile fibres

Ternary copolymers of methacrylate, methyl methacrylate, and acrylic acid mix with caprylic acid from the upper critical temperature of dissolution, which increases with an increase in the molecular weight of the copolymer. When the copolymers react with monocarboxylic acids having a long hydrocarbon radical, homogeneous mixing is not observed in the 238–443 K temperature region and the Gibbs energy of mixing increases. The Gibbs energy of mixing increases with a decrease in the concentration of acrylic acid in the molecules of the copolymer and an increase in the number of methyl groups in the molecules of the acid.Ural University, Ekaterinburg. Scientific-Research Institute of Polymers, Dzerzhinsk. Translated from Khimicheskie Volokna, No. 3, pp. 10–12, May–June, 1995.     

Synthesis and characterization of microencapsulated sodium phosphate dodecahydrate

Microcapsules loaded with sodium phosphate dodecahydrate (DSP) were prepared according to the solvent evaporation method. The microencapsulated phase‐change materials (MEPCMs) possessed methyl methacrylate crosslinked with ethyl acrylate generated poly(methyl methacrylate) (PMMA) as the coating polymer. The influences of the polymerization time, polymerization temperature, and organic solvent types on the performances of the MEPCMs were studied in this report. The results indicate that the polymerization time and temperature had barely any effect on the size but a significant effect on the surface morphology of the microphase‐change materials. The solubility of the shell material varied in different organic solvents, and this to different phase‐transition enthalpies. In addition, DSP could be encapsulated well by PMMA, and the as‐prepared MEPCMs were equipped with a good morphology and a small particle size. When toluene and acetone were used as organic solvents, the MEPCMs had an interesting energy storage capacity of 142.9 J/g at 51.51°C, and this made them suitable for different applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1516–1523, 2013     

Effect of 2-Chloro-1,3,2-dioxaphospholane on the radical polymerisation of acrylonitrile,styrene and methyl methacrylate

The effect of 2-Chloro-1,3,2-dioxaphospholane on the AIBN initiated polymerisation of acrylo — nitrile , methyl methacrylate and styrene was investigated kinetically in benzene at 60 – 80°C. With acrylonitrile normal kinetic orders with respect to monomer and AIBN could be observed with the phospholane behaving as a chain transfer agent. With methyl methacrylate and styrene it was observed that the phospholane causes enhancement of the rates due to concurrent radical and ionic polymerisation besides functioning as a chain transfer agent.