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Epoxide monomers may be cross linked with themselves, or with the addition of a co-reactant, to form epoxy; BPA is the monomer precursor for polycarbonate; Terephthalic acid is a comonomer that, with ethylene glycol, forms polyethylene terephthalate. Dimethylsilicon dichloride is a monomer that, upon hydrolysis, gives polydimethylsiloxane.
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.
In organic chemistry, functionality is often used as a synonym for functional group. For example, a hydroxyl group can also be called a HO-function. [1] [2] Functionalisation means the introduction of functional groups, for example the functionalisation of a surface [3] (e.g. silanization for the specific modification of the adhesion of a surface)
Where P is a proportionality constant, Q is the measure of reactivity of monomer via resonance stabilization, and e is the measure of polarity of monomer (molecule or radical) via the effect of functional groups on vinyl groups. Using these definitions, and can be found by the ratio of the terms. An advantage of this system is that reactivity ...
In polymer chemistry, a macromonomer (or macromer) is a macromolecule with one end-group that enables it to act as a reactive monomer and undergo further polymerization. Macromonomers will contribute a single repeat unit to a chain of the completed macromolecule. [2] [3] [4]
Another example of this is the relationship between oleic acid and elaidic acid; oleic acid, the cis isomer, has a melting point of 13.4 °C, making it a liquid at room temperature, while the trans isomer, elaidic acid, has the much higher melting point of 43 °C, due to the straighter trans isomer being able to pack more tightly, and is solid ...
In polymer chemistry, ring-opening polymerization (ROP) is a form of chain-growth polymerization in which the terminus of a polymer chain attacks cyclic monomers to form a longer polymer (see figure). The reactive center can be radical, anionic or cationic. Ring-opening of cyclic monomers is often driven by the relief of bond-angle strain.
As required by the above definition, these sheets have a periodic internal structure. A well-known example of a 2D polymer is graphene; whose optical, electronic and mechanical properties have been studied in depth. Graphene has a honeycomb lattice of carbon atoms that exhibit semiconducting properties.