Monomers


Also found in: Dictionary, Thesaurus, Medical.

Monomers

 

low-molecular-weight substances composed of molecules that interact with one another (polymerization or polycondensation) or with the molecules of other substances to form a polymer. Most of the monomers that take part in polymerization processes belong to one of two classes: (1) compounds that undergo polymerization because of the scission of multiple bonds—for example, C=C, O≡C, C=O, and C≡N (olefins, diene and acetylene hydrocarbons, aldehydes, and nitriles); and (2) compounds that polymerize because of scission of ring groups (for example, olefinic oxides, lactames, and lactones).

The monomers that take part in polycondensation reactions may be any compounds that contain no fewer than two reactive (functional) groups per molecule—for example, diamines, dicarboxylic acids, amino acids, and glycols. During polycondensation, bifunctional compounds form linear polymers, whereas compounds with more than two functions produce branched and reticular polymers.

References in periodicals archive ?
Kim and White [28] have conducted the bulk polymerization of CL monomer in a twin-screw extruder using aluminum triisopropoxide initiator under a range of processing conditions, including barrel temperature profiles, throughput, and screw speed.
Stupp and James Hulvat, also at Northwestern, have created a novel template for organizing thiophene monomers into more highly aligned arrangements.
COLUMBUS, Ohio -- In an effort to help coatings manufacturers continue to reduce residual monomer and volatile organic compounds (VOCs) in their products, Bruggemann Chemical and Hexion Specialty Chemicals have collaborated on a process that greatly enhances monomer conversion.
Copolymers of vinyl esters and crotonic acid present as film-forming agents or binders in hair sprays and hair setting lotions very frequently present the drawback that they still contain residual unreacted monomers and impurities.
The Japanese facility, scheduled to be operational last month, features a newly installed bulk tank for storage of glycidal methacrylate (GMA) monomer and direct storage facilities for hyroxyethyl acrylate (HEA) and hydroxypropyl acrylate (HPA) monomers.
Russell and co-worker Darrell Williams converted the enzyme subtilisin into a "biomonomer" that can link up with other monomers.
The commercial Catalloy process is similar in concept to Himont's developmental Hivalloy technology except that where Catalloy is an olefinic alloying process, Hivalloy products are made by co-reacting the base PP spherule with up to 50-60% by weight of non-olefinic monomers.
However, commercially available phosphonate monomers are generally very expensive and have poor reactivity (for example, vinyl phosphonic acid).
Sartomer Company has introduced 19 new monomers and oligomers for UV/EB cure systems.
Sartomer reports that its method of partial or total replacement of styrene with multifunctional acrylic monomers allows composites manufacturers to meet EPA emissions guidelines while maintaining excellent performance properties.
The template is able to control the chain propagation if it has the capability of binding the original monomers or the macroradicals which are growing in the reacting solution.