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In polymer chemistry, cationic polymerization is a type of chain growth polymerization in which a cationic initiator transfers charge to a monomer, which then becomes reactive. This reactive monomer goes on to react similarly with other monomers to form a polymer .
Polyelectrolytes that bear both cationic and anionic repeat groups are called polyampholytes. The competition between the acid-base equilibria of these groups leads to additional complications in their physical behavior. These polymers usually only dissolve when sufficient added salt screens the interactions between oppositely charged segments.
In polymer chemistry, ionic polymerization is a chain-growth polymerization in which active centers are ions or ion pairs. [2] It can be considered as an alternative to radical polymerization, and may refer to anionic polymerization or cationic polymerization. [3] As with radical polymerization, reactions are initiated by a reactive compound.
Ion-exchange resin beads. An ion-exchange resin or ion-exchange polymer is a resin or polymer that acts as a medium for ion exchange, that is also known as an ionex. [1] It is an insoluble matrix (or support structure) normally in the form of small (0.25–1.43 mm radius) microbeads, usually white or yellowish, fabricated from an organic polymer substrate.
Non-linear polymers and copolymers, and polymer assemblies are named using the italicized qualifiers in Table 2. [5] The qualifier, such as branch, is used as a prefix (P) when naming a (co)polymer, or as a connective (C), e.g., comb, between two polymer names.
An example of a widely used polymer of this class is SU-8. SU-8 was one of the first polymers used in this field, and found applications in wire board printing. [17] In the presence of a cationic photoinitiator photopolymer, SU-8 forms networks with other polymers in solution. Basic scheme shown below. SU-8 photopolyermization
Hydrocarbon-based surfactants are an example group of amphiphilic compounds. Their polar region can be either ionic , or non-ionic. Some typical members of this group are: sodium dodecyl sulfate ( anionic ), benzalkonium chloride ( cationic ), cocamidopropyl betaine ( zwitterionic ), and 1-octanol (long-chain alcohol, non-ionic).
General scheme ionic propagation. Propagating center can be radical, cationic or anionic. 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.