
Taking on a new house project? Wondering what kinda plastic to use for your windows or light fixtures? Buzzle gives you a detailed account of polycarbonate plastics vs. acrylic plastics in order to help you make a choice between the two.
Read the Label!
Most polycarbonate plastics with the label 7 or 07 may contain BPA. This chemical is capable of leaching into foods when stored in containers made from BPA-containing polycarbonate. It can disrupt normal hormone levels, increase the risk of cancer, and cause various neurological and heart problems.
The word ‘plastic’ is derived from the Greek word plastikos, i.e., capable of being molded. Plastics are organic polymers of high molecular weight. They can be natural, semisynthetic, or synthetic in nature. They are light in weight, economical to produce, highly versatile, impervious to water, and have great strength. For these reasons, plastics have become the modern-day choice for the production of say, about anything!
Plastics can be classified into two types, thermosets and thermoplastics. Thermosets set irreversibly when solidified after heating; thermoplastics, on the other hand, can be molded again after heating. Polycarbonate plastics and acrylic plastics are thermoplastics. Both these plastics are clear in texture and have distinct physical and chemical properties as a result of which they have a variety of different applications.
Polycarbonate Plastics Vs. Acrylic Plastics
Synthesis | |
✮ Polycarbonate plastics are synthesized by reacting bisphenol (BPA) and phosgene in the presence of sodium hydroxide or by transesterification of BPA and diphenyl carbonate. | ✮ Acrylic plastics are synthesized by the conversion of propylene to acetone followed by the conversion of acetone to methyl 2-methylpropenoate, which is later polymerized. |
Trade Names |
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✮ They are marketed under the names Lexan, Makrolon, MakroClear, etc. | ✮ They are marketed under the names Plexiglas, Acrylite, Lucite, etc. |
Physical Properties | |
a. Strength |
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Both are much lighter, yet stronger than glass. |
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✮ In its unmodified form, this plastic is almost unbreakable; it has an impact strength that is almost 250 times greater than that of glass. It has a tensile strength of 80 N/mm2. | ✮ Acrylic plastics are twice as thick as polycarbonate plastics in order to withstand the same impact force. They have a tensile strength of 69 N/mm2. |
b. Scratch Resistance |
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Although they have a greater impact resistance as compared to glass, they both suffer scratches. | |
✮ These plastics get scratched easily and need to be modified a little in order to develop scratch resistance. | ✮ These have greater scratch resistance as compared to polycarbonate plastics. |
c. Resistance to Ultraviolet Rays | |
✮ Resistance to ultraviolet rays is not very high in these plastics, and they may turn yellow after prolonged exposure. | ✮ Resistance to ultraviolet rays is much greater than polycarbonate plastics, and they can filter ultraviolet rays below 300nm. |
d. Transparency | |
✮ Transparency is about 88 percent for these plastics. | ✮ These plastics allow 92 percent transmission of light through them. |
e. Glass Transition Temperature | |
The temperature at brittle plastic transforms into a molten rubber-like state, which is called its glass transition temperature. | |
✮ These plastics have a glass transition temperature of 310°F and are flame-retardant in nature. | ✮ These plastics have a glass transition temperature of 190°F and are flame-retardant to some extent. |
f. Workability | |
✮ These plastics can be formed and processed at room temperature without cracking, unlike other thermoplastics. | ✮ These plastics can be formed and processed only at temperatures above 195°F. |
g. Cutting and Drilling of Plastics | |
✮ These plastics are less brittle as compared to acrylic plastics and can be drilled using a standard drill bit. Due to its higher tensile strength, this plastic shows some resistance to cutting. | ✮ These plastics are quite brittle and need a special type of drill bit. These plastics tend to crack when drilled near the edges. They can be cut with ease as compared to polycarbonate plastics. |
4. Chemical Resistance | |
Both these plastics show poor resistance to organic solvents like benzene, carbon tetrachloride, toluene, etc. | |
✮ These are seen to be damaged on exposure to acetone and alkalis. They show resistance to dilute acids. | ✮ These show less resistance to dilute acids as compared to polycarbonate plastics. |
5. Uses | |
✮ Due its good insulation properties and flame-retardant capability, it can be used in the manufacturing of insulating parts in electrical fittings. ✮ With certain modifications, this plastic can be used in the manufacture of headlights for cars. ✮ Due to its high impact resistance, this plastic can be used in the manufacture of bulletproof glass and Teller windows in banks. ✮ This plastic is usually used for eye protection gears like the ones used in viewing under ultraviolet lights, making of swimming goggles, sunglasses, and eye lenses. ✮ It is used in the manufacture of safety gears like helmets. ✮ The screen of mobile devices is usually made of this plastic. |
✮ Due to its low cost and greater impact resistance, this plastic has become a popular choice as a substitute for glass and is used in the construction of stages (it is made to look like glass) and aquariums. ✮ Due to its biocompatibility (does cause an immune response), it is used in the manufacture of lens implants as well as in the manufacture of contact lenses and dentures. ✮ It is used in the manufacture of plastic optical fibers for telecommunication. ✮ This plastic is used in the manufacture of lighting fixtures and also roofing materials. ✮ It is used as a filler in many cosmetic treatments. |
Although plastics have a variety of applications, more than 30 million tons of plastic are generated every year, and it can take up to a hundred years to break them down into simpler compounds. It, thus, becomes our responsibility to use plastics wisely, reuse them as much as possible, and recycle them so that a greener earth can be provided for the generations to come.