PMMA: The full form of PMMA is Poly methyl methacrylate. It is a most important commercial high polymer. It comes from the acrylic class. It is also known as transparent plastic or acrylic glass. Its IUPAC name is Poly(methyl 2-methylpropenoate). Other names are Poly(methyl methacrylate) (PMMA) and methyl methacrylate resin.
At high temperature the components of the long chain backbone of the polymer can begin to separate and react with one other to change the properties of the polymer this is the mechanism of degradation which has so many causes. It is of 4 types that are Heat or thermal degradation which is also of 2 types that are thermal degradation and thermal oxydative degradation causes in the presence of oxygen, light degradation called photodegradation, oxygen i.e oxydative degradation and weathering degradation generally known as UV degradation. Thermal degradation reduces the ductility and belittlement it affects on chalking, colour changes, cracking etc. For the neurotoxic designer drug PMMA, commonly sold as MDMA.
Properties: The molecular formula of PMMA or Poly methyl methacrylate is (C5O2H8)n .
It is an amorphous in nature, linear polymer valued for its hardness, rigidity in nature. it is totally visible means transparency and have properties of weathering resistance. Its molecular mass always varies and it’s density is 1.18 g/cm3. The environmental stability of PMMA is superior to most other plastics such as polystyrene and polyethylene so it has out order application. The refractive index value of PMMA is 1.4914 at 587.6 nm. 160 °C is it’s melting point in Fahrenheit scale it is 320 °F. The standard state of PMMA is 25 °C at 100 Kpa. Other notable trade names are Lucite, acrylite, Plexiglas optix, Altuglas, Oroglas, Perspex. This is a strong and light weight material. It has good impact strength and it’s density varies in 1.17–1.20 g/cm3 which is less than the half of the glass. PMMA gives reflection of about 4% from each of its surfaces on account of it’s refractive index 1.4914 at 587.6 nm and transmits upto 92% of visible light. PMMA smells and dissolved in many organic solvents and also it is poor resistance to many other chemicals. It has maximum water absorption ratio of 0.3 to 0.4 in weight, tensile strength increases with increase in water absorption. It has relatively high coefficient of thermal expansion i.e., (5–10)×10−5K−1
Application:
It exploit good impact resistance and dull shards formed upon fracture that is its glazing application. Some of its major applications are it used in the commercial purpose like making basins, birth room fixtures, sinks used in acrylic sheet birth tubes It has an wide application in automotive industry i.e., used in rear lamps, light fixtures … etc. It also has application in road lines. It gives a big application in case of medical. It made the medical instrument more advance i.e it has wide use some of that example are used in contact lenses , bone cements, it also uses in membrane dialysis. Dentists are uses this in dental restoration. Due to this wide range of application in medical we can say that it made the medical science more advance. It has good degree of compatibility with human tissue and this was discovered by WWII RAF pilots, whose eyes had riddled with PMMA splinters coming from the side windows of their Super-marine spit-fire.
Some important questions related to PMMA or high polymer:-
Q1: Molecular formula of High polymer PMMA?
Ans: (C5O2H8)n
Q2: Density of PMMA is?
Ans: 1.18 g/cm3.
Q3: IUPAC name of PMMA is?
Ans: Poly(methyl 2-methylpropenoate
Q4: Two other names of PMMA?
Ans: Poly(methyl methacrylate) (PMMA) and methyl methacrylate resin.
Q5: Example of one medical science application?
Ans: Contact lenses.