Thermoplastics polymethylmethacrylate

In comparison to bulk plastics, thermoplastic polymethylmethacrylate (PMMA) is much more expensive. Its particular characteristics are clarity, hardness, low absorbance and resistance to aqueous solutions, acids, alkalis, carbon dioxide and fat. It is attacked or dissolved by polar organic solvents. The world-wide use of PMMA in 1997 was ca. 1.2 x 106 t, principaly for optical articles in cars and buildings and glazing material in aircraft. Typical food contact articles are dishes, cups and silverware. In addition it has orthopedic and denture uses. 

Polymethylmethacrylate (Lucite, Plexiglas, Crystallite or PMMA)., A thermoplastic translucent resin of the acrylate resin family. The monomer, methylmethacrylate ... 

Some thermoplastics can also be used in casting processes in these cases polymerisation takes place in the mould which is filled with the monomer. Examples are polystyrene, polymerised from styrene, and polymethylmethacrylate from its monomer. These reactions can take place quite easily in the presence of suitable catalysts. In this way thick sheets can be produced, but also large articles such as PA-6 ship propellers or gear wheels, as polymerisation products from caprolactam. 

Acrylates. Polymethylmethacrylate (Lucite, Plexiglas, Perspex) is easily machined and is widely used with dilute aqueous solutions. Acrylates are resistant to nonoxidizing acids and weak alkalies, but are attacked by concentrated oxidizing acids and strong alkalies. They will withstand petroleum oils and most alcohols, but are generally unsuitable for use in contact with organic solvents. They are dissolved by ketones, esters, and aromatic and chlorinated hydrocarbons. They are thermoplastic and cannot be used continuously above 75 °C. The acrylates are perfectly clear and transparent and often are used to make shields or inert atmosphere enclosures. The materials bum slowly when ignited. 

A number of different polymers have been used in the production of microchip electrophoretic devices. One class of polymers is thermoplastics, which melt above a certain temperature but are hard at room temperature. Materials from this class that have been used in the formation of microchip devices include polymethylmethacrylate, polycarbonate, polyethylene, polystyrene, and a number of others. An excellent review on the fabrication and use of polymeric materials in microchips was presented by Becker and Gartner. The second class of materials is elastomeric polymers, the most widely used of which is poly(dimethylsiloxane) (PDMS). Use of this material was covered in a review by McDonald et al. ... 

Polymethylmethacrylate (POL-ee-meth-uhl-meth-AK-rill-ate) is a clear thermoplastic resin used to make windshields, visors, coatings for baths, advertising signs, and contact lenses. It is also widely used in dentistry and medicine. A thermoplastic resin is one that becomes soft when heated and hard when cooled. It can be converted back and forth any number of times between the solid and liquid states by further heating and cooling. 

Nonolefinic thermoplastic polymers that in principle may be blended with polyolefins include polyamides (nylons) such as polyamide 6, polyamide 66, polyphenylene sulfide (PPS), polyphenylene ether (PPF), and polyphenylene oxide (PPO) polyesters such as polyethylene terephthalate (PET), polybutylene terephtha-late (PBT), polyethylene naphthalate (PEN), polytrimethylene terephthalate (PTT), polycarbonates, polyethers, and polyurethanes vinyl polymers such as polystyrene (PS), polyvinyl chloride (PVC), polymethylmethacrylate (PMMA), and ethylene... 

Some Thermoplastic Construction Materials (PVC, Polymethylmethacrylate (PMMA), Polyolefins and PC) used Indoors... 

Typical thermoplastic binders which are found in literature for injection molding of ceramic bodies are, styrene-butadiene, polyethylene, polypropylene, polybutene, ethylene vinyl acetate, polymethylmethacrylate and polyoxymethylene. When selecting one of these binders for thermoplastic extrusion of ceramic bodies, it should be noted that the shrinkage of par-tially-crystalline polymers is higher than for amorphous polymers, and hence warping during cooling is more critical in the former case. This is, however, not the only criterion for selection price and processability at adequate temperatures are also important factors to consider. 

Polymethyl methacrylate themioplastic, barrier vinyl topcoats Polymethyl methacrylate thermoplastic, coatings Nucrel Resins Polymethylmethacrylate thermoplastic, extrusion coatings Eastar Bio Copolyester 14766 thermoplastic, extrusion coatings food... 

In a thermoplastic, the macromolecules are not cross-linked so that the material can melt, i.e., above the glass transition temperature, the material begins to soften. Thermoplastics can be amorphous or semicrystalline. In microfluidics, amorphous polymers are often preferred because of their optical transparency. Amorphous polymers include polymethylmethacrylate (PMMA), polycarbonate (PC), polystyrene (PS), and cyclic olefin polymers (COP) and copolymers (COC). COP and COC, unlike most other polymers, are also transparent for UV Ught... 

Hard, glassy, brittle thermoplastics such as polystyrene (PS) and polymethylmethacrylate (PMMA) have low attenuations, of order 6-10 dB/cm at 10 MHz, and in the case of PS, a low acoustic impedance. Ductile polymers such as polycarbonate (PC), many polyolefins and impact-modified thermoplastics generally have high absorption coefficients, in the range 20-40 dB/cm. The same molecular structures and mobiUty, which contribute to ductihty, may also contribute to absorption of ultrasonic energy. Not surprisingly, rubbers and, by extension, any polymer above its... 

Name given to plastics produced by the polymerization of acrylic acid derivatives, usually including methyl methacrylate. An amorphous thermoplastic material. In technological jargon polymethylmethacrylate (PMMA) or polyacrylonitrile fiber with at least 85 wt% of PAN. A mechanical reducing mechanism between the barrel and either a nozzle or a die. 

Hot-gas welding can be used to join most thermoplastics including polypropylene, polyethylene, acrylonitrile butadiene styrene, polyvinyl chloride, thermoplastic polyurethane, high-density polyethylene, polyamide, polycarbonate, and polymethylmethacrylate. For polyolefins and other plastics that are easily oxidized, the heated gas must be inert (e.g., nitrogen or argon) because hot air will oxidize the surface of the plastic. 

In this group, there are acrylics, polymethylmethacrylate (PMMA) acrylonitrile butadiene styrene (ABS), aromatic polyamides (PI), cellulosics (CA, CAB, CAP, CN), ethylene vinyl acetate (EVA), fluoroplastics (Teflon, PTFE and FEP), Nylons - polyamides - (PA), polyacetals (POM), polyethylethylketone (PEEK), polybutene-1 (PB-1), polycarbonate (PC), polyesters - thermoplastic - (PETP, PBT, PET),... 

Figure 1 Cost-related (specific) flexural strength of major thermoplastics, versus cost-related (specific) thermal tolerance. The unit cost is the market price in US cents (1992) of 1 cm plastics. The thermal tolerance is the temperature difference (AT) over room temperature (AT — T - room T), by which temperature (7 ) the flexural modulus is equal to 1 GPa. Designations, abbreviations WFRP-S, wood fiber reinforced PP (S type) of AECL, Canada (See Table 1) PMMA, polymethylmethacrylate PVC, pol)winyl chloride PS, polystyrene PP, polypropylene UP, unsaturated polyesters PA-GF, glass fiber (35%) reinforced polyamide PHR, phenolic resin EP, epoxy resin ABS, acrylonitrile/butadiene/styrene copolymer UF, urea/formaldehyde LDPE, low density polyethylene PC, polycarbonate POM, polyoxymethylene CAB, cellulose acetate butyrate LCP, liquid crystal polymers PEEK, polyether-etherketone PTFE, polytetrafluorethylene.

Thermoforming. The thermoforming process is applicable only to thermoplastic materials. In this process, a sheet of solid thermoplastic material, such as Plexiglas (polymethylmethacrylate) or polystyrene, is placed in a mold or form and heated to a temperature at which the material becomes highly pliable but does not melt. This allows the sheet to deform and adopt the shape of the mold, assisted by changing the pressure on one side of the sheet of material. The method is most suitable for designs that are relatively flat or low profile. 

A polymer is a material composed of large macromolecules. These macromolecules are formed by chains of hundreds or thousands of connected (polymerized) monomer molecules. The three main classes of polymers are thermoplastics, elastomers and thermosets. They differ in the degree of cross-linking of their macromolecules -from no cross-linking (thermoplastics) to moderate cross-linking (elastomers, rubbers) to high cross-linking (thermosets). Thermoplastics commonly used in microfluidics include materials like polymethylmethacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET) or cyclic olefin copolymers (COC). Silicones (like poly-dimethylsiloxane, PDMS) are a typical class of elastomers. Thermosets include photoresist materials like SU-8 and others. 

Several thermoplastics, both of the commodities kind [polystyrene (PS), polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), polypropylene (PP), polyvinylchloride (PVC) etc.] and engineering pol)uners [polyamides (PA), polyesters (PE), polycarbonates (PC), polyimides (PI), polysulfones (PSF), polyoxymethylene (POM), polyphenylene oxide (PPO) etc.] exhibit glass transition temperatures (Tg) higher than or close to room temperature (R.T.). As a consequence they show, at R.T. or below it, the shortcoming of brittle impact behaviour, which limits their commercial end-uses. 

Polymethylmethacrylate (PMMA) is another polymeric material frequently employed for microfluidics and micro fuel cells [4]. PMMA is one of the thermoplastic polymers that is usually linearly linked and can be softened by applying heat at above the glass transition temperature [8]. PMMA has a noncrystalUne structure with 92% light transmittance in the visible spectrum. This material also has other excellent properties such as low frictional coefficient, high chemical resistance, and good electrical insulation. All these features and properties make PMMA a good substrate for microfluidic devices, especially for those involved in chemical applications [8]. 

Acrylic resins thermoplastic material produced by polymerisation of an acrylic resin. Can be extremely clear, eg Perspex (polymethylmethacrylate). 

Two different materials were chosen for the stiffer component (Material 2), polymethylmethacrylate (PMMA) and polycarbonate (PC). They were bonded to a much softer thermoplastic elastomer (TPE) (Material 1). The bulk mechanical... 

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