Synthesis and characterization of poly(methyl methacrylate) obtained by ultrasonic irradiation

e-Polymers ◽  
2005 ◽  
Vol 5 (1) ◽  
Author(s):  
Cristina Parra ◽  
Gema González ◽  
Carmen Albano
Keyword(s):  
Methyl Methacrylate ◽  
Cationic Surfactant ◽  
Anionic Surfactant ◽  
Average Particle Size ◽  
Monomer Concentration ◽  
Average Particle ◽  
Lauryl Sulfate ◽  
Scanning Calorimetry ◽  
Absorption Bands ◽  
Poly Methyl Methacrylate

AbstractWe have studied the influence of surfactant nature and concentration, and monomer concentration on the synthesis of poly(methyl methacrylate) (PMMA) using high-frequency ultrasound. Polymerization was carried out via free radicals from aqueous solutions with several concentrations of an anionic (sodium lauryl sulfate, SLS) or a cationic surfactant (cetyltrimethylammonium bromide, CTAB) and different concentrations of the insoluble monomer methyl methacrylate (MMA) as the dispersed phase. The polymer particles obtained were characterized by FTIR, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The IR spectra show the presence of the characteristic absorption bands for PMMA when SLS was used. When CTAB was employed, for all surfactant concentrations and high monomer concentration (14% v/v), PMMA was obtained. However, bands of the surfactant were present for lower monomer concentrations. The glass transition temperature measured by DSC was in the range 106 - 126°C characteristic of PMMA. Maximum conversion was obtained when the anionic surfactant was employed. SEM studies show the formation of sub-micrometric PMMA latex spheres with average particle size from 65 to 100 nm when the anionic surfactant was used and 65 nm - 0.3 μm for the cationic surfactant.

Encapsulation of silica nanoparticles by poly(methyl methacrylate-co-styrene) via emulsion polymerization using dimethylaminoethyl methacrylate

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Mohammad Barari ◽  
Naser Sharifi-Sanjani
Keyword(s):  
Methyl Methacrylate ◽  
Silica Nanoparticles ◽  
Emulsion Polymerization ◽  
Monomer Concentration ◽  
Molar Ratio ◽  
Average Particle ◽  
Scanning Calorimetry ◽  
Potential Measurement ◽  
Emulsion Copolymerization ◽  
Dimethylaminoethyl Methacrylate

AbstractEncapsulation of silica nanoparticles was performed by emulsion copolymerization of methyl methacrylate (MMA) and styrene (St) using dimethylaminoethyl methacrylate (DM) as an auxiliary monomer. The emulsion polymerization was performed in the presence of silica nanoparticles as the seed to obtain encapsulated silica nanoparticles with polymer content and average particle sizes ranged from 35 wt. % to 85 wt. % and 114 to 272 nm respectively. Electrostatic attraction between anionic surface of silica beads and cationic amino groups of DM is the main driving force for the encapsulation of the silica nanoparticles. The influence of MMA, St and DM concentration on the coating of the silica nanoparticles was studied. It was demonstrated that DM has an important role in stabilizing the system. Transmission electron microscopy showed that coreshell structures with silica particles as core were coated with the polymer, of which the amount and morphology were influenced by the total monomer concentration and molar ratio of MMA to St. Zeta potential measurement confirmed the presence of DM on the surface of composite particles. Thermogravimetric analysis showed that the incorporation of silica in polymer matrix results in an enhancement of thermal stability in the encapsulated products. Differential scanning calorimetry studies indicated that the glass transition temperature of encapsulated particles can be either higher or lower than those of the pure terpolymer counterpart, depending on the DM content of the polymer shell. The products were also characterized by FT-IR spectroscopy.

Preparation and Characterization of CuO/Co3O4/ Poly(Methyl Methacrylate) Nanocomposites Films for Optical and Dielectric Applications

2021 ◽  
Author(s):  
S. El-Sayed ◽  
Adel El Sayed
Keyword(s):  
Methyl Methacrylate ◽  
Transition Metal Oxides ◽  
Sol Gel ◽  
Average Particle Size ◽  
Nanocomposite Films ◽  
Average Particle ◽  
Optical Parameters ◽  
Face Centered Cubic ◽  
Poly Methyl Methacrylate ◽  
Control Film

Abstract Composites of transition metal oxides (TMOs)/Polymers have many modern technological, industrial, and biological applications. Co3O4 and CuO nanoparticles (Nps) were synthesized by sol-gel. Then they doped into poly(methyl methacrylate) (PMMA) via solution casting method. The obtained Nps and nanocomposite films were then investigated using several techniques. XRD and HR-TEM indicated the high purity of Co3O4 and CuO Nps of face-centered cubic (fcc) with 58 nm average particle size (Dav), and monoclinic structure with Dav = 35 nm, respectively. The amorphous nature of PMMA was influenced after mixing with these Nps. SEM and FTIR confirmed the interaction between Nps and the polymer chains. The pure film showed transparency of about 90% and Nps addition narrowed the optical bandgap effectively while keeping the films with high transmittance. CuO is more effective than Co3O4 on the optical parameters of the films. The dielectric constant improved after adding the Nps, while all films have a low dielectric loss. Additionally, the effects of Co3O4 and CuO on the ac conductivity, Argand plots, and the dielectric modulus are reported. Our nanocomposites are considered a promising candidate for nanotechnology-based devices such as electric stress control, film capacitors and anti-reflective coating for solar cell applications.

Plasticizer effect on dielectric properties of poly(methyl methacrylate)/titanium dioxide composites

2021 ◽  
pp. 096739112110147
Author(s):  
Ufuk Abaci ◽  
H Yuksel Guney ◽  
Mesut Yilmazoglu
Keyword(s):  
Dielectric Constant ◽  
Titanium Dioxide ◽  
Dielectric Properties ◽  
Methyl Methacrylate ◽  
Pure Pmma ◽  
Segmental Mobility ◽  
Scanning Calorimetry ◽  
Poly Methyl Methacrylate ◽  
Casting Technique ◽  
Lcr Meter

The effect of plasticizer on dielectric properties of poly(methyl methacrylate) (PMMA)/titanium dioxide (TiO2) composites was investigated. Propylene carbonate (PC) was used as plasticizer in the samples which were prepared with the conventional solvent casting technique. Scanning Electron Microscopy with Energy Dispersive X-Ray Analysis (SEM-EDX) and Differential scanning calorimetry (DSC) analyses and LCR Meter measurements (performed between 300 K and 400 K), were conducted to examine the properties of the composites. With the addition of plasticizer, the thermal properties have changed and the dielectric constant of the composite has increased significantly. The glass transition temperature of pure PMMA measured 121.7°C and this value did not change significantly with the addition of TiO2, however, 112°C was measured in the sample with the addition 4 ml of PC. While the dielectric constant of pure PMMA was 3.64, the ε′ value increased to 5.66 with the addition of TiO2 and reached 12.6 with the addition of 4 ml PC. These changes have been attributed to increase in amorphous ratio that facilitates polymer dipolar and segmental mobility.

Synthesis of Emulsion for Water-Based Pigment Ink Jet

2011 ◽  
Vol 380 ◽  
pp. 81-84
Author(s):  
Li Ming Zhang ◽  
Xiu Lan Xin ◽  
Wei Jiang
Keyword(s):  
Particle Size ◽  
Water Resistance ◽  
Average Particle Size ◽  
Average Particle ◽  
Scanning Calorimetry ◽  
Reactive Surfactant ◽  
Potential Value ◽  
Ink Jet ◽  
Water Based ◽  
Pigment Ink

The water-based pigment ink jet emulsion whose particle size was less than 100nm was synthesized by the polymerization of methyl methacrylate, butyl acrylate and ethylhexyl acrylate, and anionic reactive surfactant and nonionic surfactant were used as the emulsifiers. The effects of particle size and water resistance were studied. The glass transition temperature was tested by differential scanning calorimetry. The average particle size of emulsion was range from 60nm to70nm, zeta potential value was less than -60mv; viscosity was 3.5mps; water absorption was 5.9%.

scholarly journals FORMULATION AND EVALUATION OF DOXORUBICIN CONTAINING NANOGELS FOR DELIVERY TO CANCER CELLS

2018 ◽  
Vol 8 (5) ◽  
pp. 178-183
Author(s):  
Manish Kumar ◽  
Hemant K. Sharma
Keyword(s):  
Average Particle Size ◽  
Gellan Gum ◽  
Cross Linking ◽  
Average Particle ◽  
Scanning Calorimetry ◽  
Green Method ◽  
X Ray ◽  
Oppositely Charged ◽  
Chemical Cross Linking

The objective of this study is to prepare nanogels were prepared via charged gellan gum. It was prepared by in situ cross linking reaction between two oppositely charged materials by green method without use of chemical cross linking agents. The prepared nanogels were characterized by Dynamic light scattering, scanning electron microscopy, differential scanning calorimetry and X- Ray diffractometry. The prepared formulation had average particle size of 226 nm with polydispersity index of 0.3. The doxorubicin loaded nanogel demonstrated sustained release for 20 h. The prepared nanogels were hemocompatible and cyctocompatible as revealed by hemocompatibility and MTT assay respectively. All results confirmed that these nanogels can be used for cancer treatment. Keywords: Nanogel, Chitosan, Gellan gum, Doxorubicin, Cancer.

scholarly journals Adhesive Performance of Acrylic Pressure-Sensitive Adhesives from Different Preparation Processes

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2627
Author(s):  
Irene Márquez ◽  
Núria Paredes ◽  
Felipe Alarcia ◽  
José Ignacio Velasco
Keyword(s):  
Average Particle Size ◽  
Gel Permeation Chromatography ◽  
Shear Resistance ◽  
Deformation Energy ◽  
Average Particle ◽  
Scanning Calorimetry ◽  
Pressure Sensitive Adhesives ◽  
Pressure Sensitive ◽  
Monomeric Composition ◽  
Adhesive Performance

A series of pressure-sensitive adhesives (PSAs) was prepared using a constant monomeric composition and different preparation processes to investigate the best combination to obtain the best balance between peel resistance, tack, and shear resistance. The monomeric composition was a 1:1 combination of two different water-based acrylic polymers—one with a high shear resistance (A) and the other with a high peel resistance and tack (B). Two different strategies were applied to prepare the adhesives: physical blending of polymers A and B and in situ emulsion polymerization of A + B, either in one or two steps; in this last case, by polymerizing A or B first. To characterize the polymer, the average particle size and viscosity were analyzed. The glass transition temperature (Tg) was determined by differential scanning calorimetry (DSC). The tetrahydrofuran (THF) insoluble polymer fraction was used to calculate the gel content, and the soluble part was used to determine the average sol molecular weight by means of gel permeation chromatography (GPC). The adhesive performance was assessed by measuring tack as well as peel and shear resistance. The mechanical properties were obtained by calculating the shear modulus and determination of maximum stress and the deformation energy. Moreover, an adhesive performance index (API) was designed to determine which samples are closest to the requirements demanded by the self-adhesive label market.

Influence of acrylonitrile butadiene rubber on recyclability of blends prepared from poly(vinyl chloride) and poly(methyl methacrylate)

2018 ◽  
Vol 36 (6) ◽  
pp. 495-504 ◽  
Author(s):  
Sunil S Suresh ◽  
Smita Mohanty ◽  
Sanjay K Nayak
Keyword(s):  
Methyl Methacrylate ◽  
Vinyl Chloride ◽  
Butadiene Rubber ◽  
Scanning Calorimetry ◽  
Elongation At Break ◽  
Poly Methyl Methacrylate ◽  
Impact Performance ◽  
Acrylonitrile Butadiene Rubber ◽  
Poly Vinyl Chloride ◽  
Spectroscopy Studies

The current investigation deals with the recycling possibilities of poly(vinyl chloride) and poly(methyl methacrylate) in the presence of acrylonitrile butadiene rubber. Recycled blends of poly(vinyl chloride)/poly(methyl methacrylate) are successfully formed from the plastic constituents, those are recovered from waste computer products. However, lower impact performance of the blend and lower stability of the poly(vinyl chloride) phase in the recycled blend restricts its further usage in industrial purposes. Therefore, effective utilisation acrylonitrile butadiene rubber in a recycled blend was considered for improving mechanical and thermal performance. Incorporation of acrylonitrile butadiene rubber resulted in the improvement in impact performance as well as elongation-at-break of the recycled blend. The optimum impact performance was found in the blend with 9 wt% acrylonitrile butadiene rubber, which shows 363% of enhancement as compared with its parent blend. Moreover, incorporated acrylonitrile butadiene rubber also stabilises the poly(vinyl chloride) phase present in the recycled blend, similarly Fourier transform infrared spectroscopy studies indicate the interactions of various functionalities present in the recycled blend and acrylonitrile butadiene rubber. In addition to this, thermogravimetric analysis indicates the improvement in the thermal stability of the recycled blend after the addition of acrylonitrile butadiene rubber into it. The existence of partial miscibility in the recycled blend was identified using differential scanning calorimetry and scanning electron microscopy.

Al2O3-Water Nanofluids for Heat Transfer Application

MRS Advances ◽  
2019 ◽  
Vol 4 (28-29) ◽  
pp. 1611-1619 ◽  
Author(s):  
Lakshita Phor ◽  
Tanuj Kumar ◽  
Monika Saini ◽  
Vinod Kumar
Keyword(s):  
Heat Transfer ◽  
Heat Load ◽  
Volume Fraction ◽  
Average Particle Size ◽  
Power Input ◽  
Experimental Investigations ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
External Power

AbstractThis manuscript aims at synthesizing Al2O3-de-ionized water nanofluid and constructing a practical design of self-cooling device that does not require any external power input. Crystalline phase of powder was confirmed by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) showed the various functional groups and absorption bands and average particle size was calculated to be 58.608 nm by Field Emission Scanning Electron Microscopy (FESEM) annealed at 900K. Experimental investigations were carried out to determine the effect of volume fraction of Al2O3 nanoparticles in the nanofluid on the rate of heat transfer from heat load to heat sink. Temperature of heat load was taken as 80° C. According to our results, cooling by 15°C, 13°C and 12°C was attained when volume fraction of nanoparticles was 1.5%, 1% and 0.5% respectively. The thermal conductivity was also measured and found to be increasing with the concentration of nanoparticles in nanofluid. Hence, indicating the use of nanofluids with suitable concentration in various cooling applications.

A Calcination Technology for Ultrafine La3NbO7 Powder Prepared by Sol-Gel Process

2011 ◽  
Vol 412 ◽  
pp. 271-274
Author(s):  
Ying Li ◽  
Qiang Xu ◽  
Ling Dai
Keyword(s):  
Single Phase ◽  
Sol Gel ◽  
Average Particle Size ◽  
Complex Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Acid Complex ◽  
Calcination Process ◽  
Sol Gel Process

In order to prepare ultrafine La3NbO7 powder, a potential material for thermal barrier coatings, the calcination process of La3NbO7 was studied in this paper.The precursor of La3NbO7 was synthesized by using a citric acid complex method. A calcination process had been systematically investigated. The reaction temperature was determined by differential scanning calorimetry (DSC). The phase composition of powders was characterized by X-ray diffraction (XRD), and the morphology was obtained by scanning electron microscope (SEM). The results revealed that the single-phase La3NbO7 powder could be successfully prepared while the calcination temperature exceeded 800°C and a better morphology could be maintained at 800°C for 4 hours. Considering all above, an optimum calcination scheme was adopted at 800°C for 4 hours. The as-prepared La3NbO7 powders had a grain size of about 50nm and an average particle size of about 300nm.

Sign in / Sign up

Export Citation Format

Share Document