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MMA is a raw material for the manufacture of other methacrylates. These derivatives include ethyl methacrylate (EMA), butyl methacrylate (BMA) and 2-ethyl hexyl methacrylate (2-EHMA). Methacrylic acid (MAA) is used as a chemical intermediate as well as in the manufacture of coating polymers, construction chemicals and textile applications.
Methacrylic acid, abbreviated MAA, is an organic compound with the formula CH 2 =C(CH 3)CO 2 H. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor.
The mass-average molecular mass, M w, is also related to the fractional monomer conversion, p, in step-growth polymerization (for the simplest case of linear polymers formed from two monomers in equimolar quantities) as per Carothers' equation: ¯ = + ¯ = (+), where M o is the molecular mass of the repeating unit.
It is applied to alkylated methacrylate monomers and the initiator is a silyl ketene acetal. New monomer adds to the initiator and to the active growing chain in a Michael reaction. With each addition of a monomer group the trimethylsilyl group is transferred to the end of the chain.
Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...
The degree of polymerization, or DP, is the number of monomeric units in a macromolecule or polymer or oligomer molecule. [1] [2] [3]For a homopolymer, there is only one type of monomeric unit and the number-average degree of polymerization is given by ¯ ¯ = ¯, where ¯ is the number-average molecular weight and is the molecular weight of the monomer unit.
Bulk polymerization or mass polymerization is carried out by adding a soluble radical initiator to pure monomer in liquid state. The initiator should dissolve in the monomer. The reaction is initiated by heating or exposing to radiation. As the reaction proceeds the mixture becomes more viscous.
To determine approximate molecular weight, the elution volumes of compounds with their corresponding molecular weights are obtained and then a plot of “K av ” vs “log(Mw)” is made, where = / and Mw is the molecular mass. This plot acts as a calibration curve, which is used to approximate the desired compound's molecular weight.