Reactive oligomers

Certain polymeric stmctures can also be blended with other coreactive polymers or multifunctional reactive oligomers that affect curing reactions when exposed to ir radiation. These coreactive polymers and cross-linking oligomers undergo condensation or addition reactions, which cause the formation of network stmctures (Table 9) (4,5,47). 

Shutov, F. A. Foamed Polymers Based on Reactive Oligomers, Vol. 39, pp. 1-64. 

Shimidzu, I. Cooperative Actions in the Nucleophile-Containing Polymers. Vol. 23, pp. 55-102. Shutov, F. A. Foamed Polymers Based on Reactive Oligomers, Vol. 39, pp. 1-64. 

It can be arranged that these oligomers contain a reactive end group, e.g., hydroxyl, carboxyl, allowing subsequently further polymerisation with a different reactant monomer to take place. These reactive oligomers are called macromers. 

There is a current drive in microlithography to define submicron features in bilevel resist structures. The introduction of organometallic components, most notably organosilicon substituents, into conventional resists is one promising approach. To this end, organosilicon moieties have been primarily utilized in starting monomers (1-4) or in post-polymerization functionalization reactions on the polymer (5,6). Little work has been done on the reaction of preformed reactive oligomers to synthesize block copolymer systems. 

The reactive oligomer which is an important ingredient in the present research can be obtained by the polycondensation of an alkylol derivative of urea or alkalation alkylol derivative with N-alkylolacrylamide in the presence of acid or its salt. 

Epoxies - The term "reactive oligomer" is relatively new but the concept is fairly old. This concept has been used for many years with systems such as epoxies, phenolics, unsaturated esters, cyanates, isocyanates and many other crosslinked systems. An example of a 177°C curing epo y system (Narmco s 5208) which was introduced into the marketplace about 1971 is shown in Eq. 1. 

Cyanamides - Cyanamides also represent a class of materials where reactive oligomers have been prepared. A representative example of the type of modification done to cyanamides to moderate the initial reaction to obtain linear soluble melt-processable oligomers 1s shown in Eq. 2. A bis(aryl sulfonyl cyanamide) was initially reacted with two moles of a bis (cyanamide) to yield an oligomeric mixture (ideally represented in Eq. 2 as a simple compound). These fire-resistant materials have shown promising properties as composite resin matrices (6). 

Other Reactive Oligomers - In the mid 1960 s, a reactive oligomeric precursor to a polybenzimidazole (PBI) was available as... 

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