Surface modification on PMMA : PVDF polyblend: hardening under chemical environment

Abstract

The influence of chemical environment on polymers include the surface alteration as well as other deep modifications in surface layers. The surface hardening, as an effect of organic liquids on poly(methyl methacrylate): poly(vinylidene fluoride) (PMMA: PVDF), which is one of the few known miscible blends, has been detected using microhardness testing. Organic liquids like acetone, toluene, xylene and benzene were introduced on the surface of blend specimens for different durations. Vickers microhardness (H v) was measured for treated and untreated specimens. The study reveals both hardening and plasticization of specimens at different exposure times. The degree of surface hardening is maximum under acetone treatment. All the specimens exhibit surface hardening at an exposure time of 1 h with all the four liquids. This feature is prominent with longer exposures for specimens with increasing content of PVDF. However, the degree of hardening decreases with the time of exposure in the respective environments. In general, acetone and toluene impart surface hardening, whereas, xylene and benzene soften the specimen. PMMA: PVDF (83 : 17) blend exhibits surface hardening under all the four treatments when compared with the respective untreated specimens.

Structural, morphological and micromechanical studies on fly ash reinforced PMMA composites

“…The sol-gel method (Celik et al 2008;Chand and Vashishtha 2008;Bajpai et al 2002Bajpai et al , 2003aGupta et al 2007;Ramrakhiani et al 2005) has been utilized to prepare the composite films of pure Poly(methyl methacrylate) and fly ash based composite films, dimethylformamide has been taken as solvent. Fly ash and Poly(methyl methacrylate) solution were mixed with the help of an electric motor operating at 200 rpm in air atmosphere at 60°C for 6 h. A Known quantity of the homogeneous solution poured in glass mould of size 4 9 4 cm 2 and kept in an electronic oven at 110°C temperature for 3 h. The oven was then switched off and the glass mould along with the solution was given sufficient time to cool down (nearly 24 h).…”

“…In the recent years the micro indentation technique of determining the microhardness has increasing use for the characterization of polymer, homopolymer, polymer blends, composite, biopolymer, copolymer (Dubey et al 2008;Bajpai et al 2002Bajpai et al , 2003aGupta et al 2007;Mishra et al 2007). The microhardness studies has been carried out on pure Poly(methyl methacrylate) polymer and fly ash reinforced Poly(methyl methacrylate) composite films with the help of mhp160 micro hardness tester, equipped with the Vicker's diamond pyramidal indenter having a square base and 136°pyramidal angle attached to the Carl Zeiss NU2 Universal Research Microscope.…”

Polymerization of Vinylidene Difluoride in Supercritical Carbon Dioxide

“…Since PMMA is miscible with PVDF [82,83] a PMMA block of a block copolymer ensures strong interactions between the PVDF and the CO 2 -phobic segments of the potential stabilizer. The second block was made of PF8H2A, for this polymer is known to be well soluble in sc-CO 2 [43].…”

Design and fabrication of piezoelectric nanocomposite structures for microdevice applications

“…5 It is widely used in engineering applications due to its favorable chemical and mechanical properties, high-piezoelectric coefficient, good flexibility, and biocompatibility. [6][7][8] Thus, ceramic nanoparticles of barium titanate oxide (BaTiO 3 ) are of great interest for microsystem applications, where high-electromechanical performance is required. [9][10][11] Combination of ferroelects, piezoelectric, and thermoelectric properties of BaTiO 3 make it interesting in electro-ceramic industry, nonlinear optics, miniaturized electronic devices, etc.…”