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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.
Taking star polymers as an example, RAFT differs from other forms of living radical polymerization techniques in that either the R- or Z-group may form the core of the star (See Figure 10). While utilizing the R-group as the core results in similar structures found using ATRP or NMP, the ability to use the Z-group as the core makes RAFT unique.
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 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.
Composition drift in some degree will occur unless the reactivity ratios for both monomers are equal to 1. In this case, each monomer prefers reaction with itself and the other monomer equally. This causes equal rates of consumption for copolymer formation and leads to random copolymerization. [3]
A colorless liquid, it is a common monomer for the preparation of acrylate polymers. [1] It is typically polymerized under free-radical conditions. [2] Ethyl methacrylate was first obtained by treating ethyl 2-hydroxyisobutyrate with phosphorus pentachloride in a dehydration reaction. [3]
However, in the event of crosspolymerization adding the other monomer, the chain-end will continue to add the new monomer and form a block copolymer.. If both ratios are near 1, a given monomer will add the two monomers with comparable speeds and a statistical or random copolymer is formed.
For example, it would be unwise to choose completely hydrophobic monomers to be imprinted with a highly hydrophilic substrate. These considerations need to be taken into account before any new MIP is created. Molecular modelling can be used to predict favourable interactions between templates and monomers, allowing intelligent monomer selection.