Effect Of Methyl Methacrylate Research Articles

The effect of acrylate on the properties and machinability of alumina ceramics

Effect of methyl methacrylate (MMA) as a binder and heating treatment were investigated to improve green alumina compacts machinability. Properties of green compacts and their corresponding sintered samples prepared with and without MMA were compared. Investigation of green and sintered properties was performed on samples compacted at applied pressures up to 150 MPa. After pressing, samples with MMA were thermally treated at 115oC. The intention was to enhance the polymerization of MMA at a temperature a little higher than the glass transition temperature (Tg = 103oC) of poly (methyl methacrylate). Green compacts with MMA had higher green density values than those without MMA. Sintered samples with MMA had lower values of sintered density and higher values of total porosity; after sintering, relative linear shrinkage was around 15 % for the whole range of applied pressures. The possibility of easily machining the green compacts with MMA produces great possibilities for application in many fields

Application of Spectroscopic Analysis for Plasma Polymerization Deposition onto the Inner Surfaces of Silicone Tubes

In the current study, plasma-polymerized methyl methacrylate (PP-MMA) generation on the inner surface of a silicone tube was performed in a capacitively coupled discharge reactor. The possibility of generating plasma inside the tube was analyzed and calculated by using optical emission spectroscopy (OES). A hollow cathode model was first proposed to determine whether plasma discharge would be generated inside the tube in the low-pressure regime. Since the ignition of plasma inside the tube is necessary for the initiation of polymerization processes, the sheath thickness was calculated analytically. To achieve the goal, the electron temperature and density of plasma should be determined beforehand. In this study, the electron temperature and plasma density were measured and calculated according to OES spectra using both the modified Boltzmann plot and the line-ratio method. The results reveal that the occurrence of plasma inside the tube can be achieved if the tube’s inner diameter is greater than two times the thickness of the sheath. The effect of methyl methacrylate (MMA) monomer concentration on sheath thickness, and, hence, plasma generation and deposition, was investigated in the presence of argon plasma and MMA monomer. According to the study, one could control the ignition of plasma discharges inside the tube followed by plasma polymerization deposition. The OES method was also applied to identify the presence of the excited species related to the fragmented monomer. The deposition of PP-MMA films on the inner surface of the tube was confirmed via attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy.

THE EFFECT OF METHYL METHACRYLATE ON THE PROPERTIES OF SYNTHESIZED ACRYLATE EMULSIONS

The effect of methyl methacrylate (MMA) addition on the properties of synthesized acrylate emulsions based on butyl acrylate (BA) and 2-ethylhexyl acrylate (EHA) was investigated. The samples were synthesized by addition of MMA in copolymer structure, ranging from 10 to 50 wt% of the total mass of BA and EHA. Fourier transformation infrared (FTIR) spectroscopy was used to analyze the molecular structure of synthesized acrylate emulsions and the results confirmed that a quantitative polymerization reaction occurred. The analysis of thermal properties showed that the addition of methyl methacrylate increases the glass transition temperature of the acrylate films obtained by drying the synthesized emulsions. The tensile strength and elongation at break increased proportionally with the increase of the content of MMA in the synthesized samples. Since the obtained acrylate materials can be used to improve the water impermeability of paper and other materials, the obtained emulsion was applied in a thin layer on a sheet of paper and the resistance of the paper to water and oil was investigated. The results showed that all emulsions were impermeable both to water and oil.

Effect of methyl methacrylate on the properties of transparent flame retardant unsaturated phosphate ester copolymer

The effect of methyl methacrylate (MMA) on the properties of transparent flame retardant unsaturated phosphate ester copolymer (poly[UPE‐co‐MMA]) prepared by bulk polymerization technique was investigated. Fourier transform infrared spectra, gel fraction (G) test, and dynamic mechanical analysis revealed the structure and crosslinking density of poly(UPE‐co‐MMA) copolymers. The thermal degradation and flame retardancy of copolymers were indicated by thermogravimetric analysis, limiting oxygen index (LOI), and microscale combustion calorimeter (MCC) test. Besides, the mechanical properties and transparency were tested with testing machines and solid ultraviolet absorption spectra. As the MMA content increased to 50%, the copolymer contained 50 wt% MMA showed the maximal G (88.93%) and transmittance was up to 91.72%. From the poly(UPE‐co‐MMA) copolymers, the tensile strength increased from 14.62 to 26.95 MPa, assigned to the increase of crosslinking density of copolymers. The char yield of poly(UPE‐co‐MMA) was up to 21.18 wt%, which was a result of decomposition of phosphate groups, producing a phosphorus‐rich layer that increased the thermal stability of the residues. LOI and MCC results confirm that the introduction of MMA can retain the flame retardancy of copolymer remarkably. POLYM. ENG. SCI., 59:2103–2109, 2019. © 2019 Society of Plastics Engineers

Synthesis and Characterization of Poly(Glycerol Sebacate)-co-Lactic Acid via Gamma Irradiation

The gamma irradiation was utilized to facilitate the synthesis of poly (glycerol sebacate)-co-lactic acid (PGS-co-LA). The effect of methyl methacrylate (MMA) crosslinker and varying dosage of irradiation to the structural composition and thermal properties of the synthesized PGS-co-LA was investigated. Compositional analyses of the polymer materials using infrared spectroscopy confirm the covalent formation of ester linkage. The use of methyl methacrylate enhances the formation of the characteristic bonds in the polymer structure. The intensity of these peaks increases with increasing irradiation dosage and high amount of crosslinker. The melting temperature of the PGS-co-LA becomes more negative with the incorporation of high amount of MMA.

Effect of methyl methacrylate and butyl methacrylate copolymer on the physico-mechanical properties of acryl syrup for paints

The present study deals with the physico-mechanical properties of acryl syrups paint, which are made from copolymer powder and methyl methacrylate (MMA) monomer. Copolymer powders were used based on MMA and butyl methacrylate (BMA). The effect of copolymer powder to MMA- monomer ratio on the physico-mechanical properties acryl syrup mixes for paint applications was investigated. Testing included pot-life, curing time, viscosity, tensile strength, elongation, water absorption and hardness shore A. The results showed that, not only monomer composition of the copolymer but also the ratio of copolymer to MMA-monomer affected the physico-mechanical properties of acrylic films. The tensile strength, hardness, pot-life, curing time and hardness of the acrylic film increased with the increase of the MMA ratio in copolymer and decrease content of copolymer in acrylic syrup mixes. In conclusion, low copolymer content and high MMA ratio in copolymer (MMA/BMA) powders are desired to produce paint with physico-mechanical properties.

Mechanical performance, water absorption behavior and biodegradability of poly(methyl methacrylate)-modified starch/SBR biocomposites

Natural corn starch was modified by surface grafting with poly(methyl methacrylate) (PMMA) through emulsion copolymerization and then compounded with styrene-butadiene rubber (SBR) latex in order to prepare PMMA-modified starch/SBR biocomposites. The effect of methyl methacrylate (MMA) and starch concentration on the mechanical properties, morphology, toluene swelling behavior, water absorption behavior and biodegradabil- ity of PMMA-modified starch/SBR biocomposites was investigated. Results showed that the optimum mechanical properties were achieved when the concentrations of MMA and starch were 10 and 30 phr, respectively, which could be also confirmed through the observations from FE-SEM micrographs and equilibrium welling test. Guth-Gold and Halpin-Tsai models were employed to predict the modulus of PMMA-modified starch/SBR biocomposites. Halpin- Tsai model was better fitted with the experimentally measured data than Guth-Gold model. The water absorption ratio of PMMA-modified starch/SBR biocomposites was strongly influenced by the immersion time and the starch concentration, which further caused a significant effect on the biodegradability of biocomposites.

Gamma‐induced polymerization and grafting of a novel phosphorous‐, nitrogen‐, and sulfur‐containing monomer on cotton fabric to impart flame retardancy

AbstractDiethyl (acryloyloxy) ethylthiophosphoramidate (DEAETPN), a novel phosphorus‐, nitrogen‐, and sulfur‐containing monomer, was synthesized in a two‐step reaction. The monomer was polymerized and grafted onto cotton fabric by gamma radiation method. Effect of methyl methacrylate (MMA) on percentage grafting (Pg) of DEAETPN on cotton fabric was studied, and it was found that small amount of MMA increases Pg on cotton fabric. The monomer, polymer, and the grafted cotton fabric were characterized by spectroscopic and thermogravimetric techniques. Flame retardant property of the modified cotton fabric was studied by the Shirley Manual Flammability Tester. The flame retardancy of cotton‐g‐DEAETPN by gamma radiation method and living radical polymerization method was compared. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Effect of Methyl Methacrylate– Acrylonitrile -Butadiene–Styrene (MABS) on the Mechanical and Thermal Properties of Poly (Methyl Methacrylate) (PMMA)-Fly Ash Cenospheres (FAC) Filled Composites

With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by preparation of polymer blends gives rise to new materials with tailored properties. More complex, three-component systems, obtained by the addition of polymeric modifier to polymer filled composites may be of interest. Use of Fly ash cenospheres is very attractive because it is inexpensive and its use can reduce the environmental pollution to a significant extent. In the present study, Poly (Methyl Methacrylate) (PMMA)-Fly ash cenospheres composites were prepared using extrusion followed by Injection molding. The effect of matrix modification with Methyl methacrylate– acrylonitrile -butadiene–styrene (MABS) on the performance of PMMA- Fly ash cenospheres compositions was also, studied. It was found that with the addition of Fly ash cenospheres particulate as filler in PMMA showed marginal reduction in Tensile Strength, % Elongation and Impact strength and improvement in Flexural Strength, Heat Deflection Temperature and Vicat Softening Point. Compared with PMMA-cenospheres composites, the notched Impact Strength of the PMMA/MABS/cenospheres composites showed marginal enhancement in values at higher loading of cenospheres. The optimum performances in mechanical and thermal properties were obtained when the ratio of MABS to cenospheres was 1:2.

Flavouring Group Evaluation 5, Revision 1 (FGE.05Rev1):Esters of branched‐ and straight‐chain aliphatic saturated primary alcohols and of one secondary alcohol, and branched‐ and straight‐chain unsaturated carboxylic acids from chemical groups 1, 2, and 5 (Commission Regulation (EC) No 1565/2000 of 18 July 2000) ‐ Opinion of the Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in contact with

Flavouring Group Evaluation 5, Revision 1 (FGE.05Rev1):Esters of branched‐ and straight‐chain aliphatic saturated primary alcohols and of one secondary alcohol, and branched‐ and straight‐chain unsaturated carboxylic acids from chemical groups 1, 2, and 5 (Commission Regulation (EC) No 1565/2000 of 18 July 2000) ‐ Opinion of the Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in contact with

Reduction of Toxic Effect of Methyl Methacrylate on Human Cells in Culture Containing Sodium Hypochlorit

The effect of sodium hypochlorite (SH) upon toxic response of cultured human fibroblasts to methyl methacrylate (MMA) which is a part of bone cement «Polacris» has been studied. Toxic effect of MMA in clinically adequate concentrations demonstrated dose-dependant suppression of total activity of mitochondrial enzymes and that was one of the showings of stress at the cellular level. MMA:SH mixture in volume ratio 1:1 and 10:1 caused reliable reduction of toxic effect on cultured cells as compared with pure MMA of the similar concentration. On the contrary, MMA: SH mixture in volume ratio 1:10 resulted in true decrease of fibroblasts viability as compared with the state of cells in presence of pure MMA. Thus it was shown that chemical experimental in vitro inactivation of MMA could be achieved only when MMA concentration was either higher or equal to SA concentration. That provided the reduction of metabolic disturbances in cells.

DIFFERENTIAL REGULATION OF IN VITRO CYTOKINE PRODUCTION BY HUMAN BLOOD CELLS IN RESPONSE TO METHYLMETHACRYLATE

The effect of methylmethacrylate (MMA) on human whole blood cultures (WBC) obtained from healthy donors was investigated. Lymphocyte transformation and cytokine production, that is, interleukin 6 (IL-6), interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha), were used to evaluate the immunological activities of MMA. Primary cytotoxicity testing of MMA in Jurkat cells showed that this compound decreased the cell proliferation to 50% at a concentration of >60 mmol/L. Similarly, MMA significantly decreased lymphocyte transformation in either phytohemagglutinin (PHA) or Staphylococcus aureus protein A (SpA) activated WBC at 100 mmol/L. In contrast to activated WBC, MMA had no observed effect on resting blood cells. Cytokine expression in WBC seemed differentially modulated by MMA. There was a tendency for IL-6 production in both resting and PHA-stimulated WBC to be upregulated, while IL-6 induced in SpA stimulated cultures was downregulated. TNF-alpha was slightly increased by MMA in resting WBC at early incubation periods, and it was slightly downregulated in response to PHA or SpA activation. Suppression of IFN-gamma secretion was observed in WBC with or without PHA or SpA stimulation. The overall results demonstrated that MMA at physiological levels could influence the cytokine production in normal human blood cells in vitro. Alterations of cytokine production patterns by MMA indicate that this compound has multiple regulatory effects on immune reactions in normal human blood.

Structure and properties of styrene–divinylbenzene–methylmethacrylate terpolymers—I. effect of methylmethacrylate as third comonomer

A series of macroporous terpolymer beads were synthesized by suspension polymerization of styrene–divinylbenzene and variable content of methylmethacrylate. A DVB content of 20 wt% and a mixture of 80/20 vol% n-heptane/2-ethyl-1-hexanol as diluent were used throughout this study. The influence of methylmethacrylate on mean droplet diameter and porous structure and swelling in toluene and cyclohexane was investigated. The porosity of the terpolymers increases with increasing MMA concentration.

Effect of methyl methacrylate on mitochondrial function and structure

1. 1. Treatment of isolated rat liver mitochondria with methyl methacrylate (MM) produced membrane disruption as evidenced by the release of citrate synthase, and changes in the ultrastructure of mitochondria. 2. 2. At concentration 0.1%, MM uncoupled oxidative phosphorylation as evidenced by stimulation of state 4 respiration supported either by pyruvate plus malate or succinate (+rotenone) and ATP-ase activity in intact mitochondria. 3. 3. At concentration 1% MM stimulated ATP-ase activity in intact mitochondria and succinate (+rotenone) oxidation at state 4 and was without effect on this substrate oxidation at state 3. 4. 4. MM inhibited pyruvate plus malate oxidation either at state 3 or in the presence of uncoupling agents. 5. 5. MM inhibited the NADH oxidase of electron transport particles at a concentration which failed to inhibit either succinic oxidase or the NADH-ferricyanide reductase activity. 6. 6. The data presented suggest that in the isolated mitochondria MM inhibits NADH oxidation in the vicinity of the rotenone sensitive site of complex I. 7. 7. The general conclusion is that MM may block an electron transport and to uncouple oxidative phosphorylation in rat liver mitochondria. The overall in vitro effect would be to prevent ATP synthesis which could result in cell death under in vivo conditions.

Effect of methyl methacrylate on isolated atria and interaction with isoproterenol, atropine and calcium chloride

1. 1. Spontaneous rate and contractile force of isolated rat and rabbit atria suspended in a tissue bath were recorded before and after drugs. Methyl methacrylate monomer (MMA) alone both decreased force and increased rate dose-dependently. 2. 2. Concentrations of calcium chloride or isoproterenol that alone increased both rate and force of rat atrial contraction were fully and only partially able, respectively, to restore force to normal after MMA. 3. 3. Atropine prevented changes in rat atrial function from low-effective doses of MMA, but not higher ones; it also failed to prevent the reduction of contractile force by a calcium channel blocker, verapamil. 4. 4. There are similarities but also differences between actions of MMA and verapamil on rat atria.

Effect of methyl methacrylate on selected lipids in rat brain and sciatic nerve.

Effect of methyl methacrylate on selected lipids in rat brain and sciatic nerve.

The effect of methylmethacrylate on bacterial phagocytosis and killing by human polymorphonuclear leukocytes.

The phagocytic and bactericidal activities of human polymorphonuclear leukocytes in the presence of methylmethacrylate were determined by in vitro techniques. It was found that methylmethacrylate in concentrations as low as 0.156 per cent significantly decreased the ability of leukocytes to phagocytose and kill strains of Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli. The evidence indicates that methylmethacrylate impairs the killing more than the phagocytosis by the leukocytes.

The effect of methylmethacrylate on chemotaxis of polymorphonuclear leukocytes.

The effect of methylmethacrylate on chemotaxis of polymorphonuclear leukocytes was evaluated by an in vitro method that involved migration of human leukocytes under agarose. Chemotactic factors produced during growth of Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli remained chemotactically active in the presence of a methylmethacrylate concentration of 1.25 per cent, which was the highest tested. The methylmethacrylate also did not alter the activity of the chemotactic factor produced by zymosan activation of normal human serum. However, when methylmethacrylate was added to normal human serum prior to zymosan activation, a methylmethacrylate concentration of 0.312 per cent significantly depressed the subsequent zymosan-induced chemotactic activity and concentrations above 0.312 per cent abolished it. When methylmethacrylate was added to the polymorphonuclear leukocyte suspensions, there was significant depression of the migration of cells at a concentration of 0.312 per cent, and at concentrations of 0.625 and 1.25 per cent no leukocyte migration occurred.

The Effect of Methylmethacrylate on the Bacterial Inhibiting Properties of Normal Human Serum

In vitro evaluation of the effect of known concentrations of methylmethacrylate on the bacterial inhibiting properties of normal human serum has been carried out. In low concentrations, methylmethacrylate was found to abolish almost completely the growth inhibition of Staphylococcus epidermidis by normal human serum. Normal human serum did not have an effect on growth of Staphylococcus aureus. It did inhibit growth of Escherichia coli, but there was no reversal of this effect by methylmethacrylate.

The Effect of Methylmethacrylate on Complement Activity

The effect of methylmethacrylate on the activity of the complement sequence has been investigated in vitro by standard hemolysis techniques. It was demonstrated that concentrations of methylmethacrylate monomer as low as .25% inhibit the reactions of the complement sequence by 50%. Methylmethacrylate concentrations of 2.5 to 5.0% abolished all complement activity. This effect is on the late-acting components of the complement sequence which are important for chemotaxis of polymorphonuclear leukocytes, immune adherence of bacteria to polymorphonuclear leukocytes, phagocytosos of bacteria by polymorphonuclear leukocytes, and bacteriolysis.