Synthesis and properties of polydiene and polypentenamer having formyl or hydroxymethyl groups and their photosensitive derivatives

Abstract

cis‐1,4‐Polybutadiene and polypentenamer having pendant functional groups such as formyl, aldoxime, hydroxymethyl, or cinnamoyloxymethyl groups have been prepared, and some of their properties were investigated in terms of structural effect on physical properties of these polymers. cis‐1, 4‐Polybutadiene and polypentenamer having a different content of formyl group were prepared by the hydroformylation reaction with rhodium catalyst under mild conditions. The pendant formyl group was reduced to a hydroxymethyl group by using various reducing agents such as sodium borohydride or sodium trimethoxyborohydride which were effective to avoid a crosslinking reaction among the formyl groups. Glass transition temperature of polypentenamer having hydroxymethyl groups increased with increasing the content of the hydroxymethyl groups in the polymer. Cinnamoyl group was introduced into the polypentenamer having hydroxymethyl groups by reacting with cinnamoyl chloride so as to prepare a photosensitive rubber. The relationships between the photosensitivity of the cinnamoylated polypentenamer and the mobility of polymer main chains have been elucidated. A linear relationship between the photodimerization rate constant and the difference between ultraviolet (UV) irradiation temperature and the glass transition temperature of the polymer was found. It has become apparent that the photosensitivity of cinnamoylated polypentenamer can be estimated by the glass transition temperature of the original polymer, UV irradiation temperature, activation energy of the dimerization, and γ, which is a coefficient of the relationship between the photosensitive group concentration and the glass transition temperature of the polymer.

Metal-Catalyzed Postpolymerization Strategies for Polar Group Incorporation into Polyolefins Containing C–C, C═C, and Aromatic Rings

“…After that initial report, many studies on the hydroformylation of different polybutadiene (PBD) systems and styrene–butadiene block copolymers (SBR) were reported using rhodium catalysts under similar conditions . As an example, Mills and co-workers studied , the hydroformylation of low-molecular-weight 1,2-PBD and 1,4-PBD in the presence of that Wilkinson’s catalyst and an excess of triphenylphosphine.…”

“…After that initial report, many studies on the hydroformylation of different polybutadiene (PBD) systems and styrene− butadiene block copolymers (SBR) were reported using rhodium catalysts under similar conditions. 37 As an example, Mills and co-workers studied 38,39 the hydroformylation of lowmolecular-weight 1,2-PBD and 1,4-PBD in the presence of that Wilkinson's catalyst and an excess of triphenylphosphine. They showed that hydroformylation of 1,2-syndiotactic polybutadiene resulted in the selective formation of terminal-branched aldehydes as the major product with a trace amount of the iso(secondary)-branched product (Scheme 5C).…”

Novel polymeric alcohols by controlled catalytic polymer functionalization

“…It was found that for EPDM polymers Rh(acac)(CO), (acac = acetylacetonate) was as effective a catalyst for hydroformylation as was HRh(CO(PPh3)3/PPh3. Rh(a~ac)(CO)~ could be used to hydroformylate EPDM polymers with as little as 10 up step is often not necessary to remove such small quantities of catalyst from the reaction mixture. The polymer can often be taken on to the next reaction without any interference from the residual catalyst.…”

UV-light induced crosslinking reaction of cinnamate natural rubbers: Effect of the spacer length, counter-ion nature, and content

“…The maleic residues were then esterified behavior with chemical structure. [3][4][5] One of the with glycol cinnamates, giving rise to half-esters, features required to improve reactivity seems to in which the cinnamate groups were separated be chain mobility. In this regard, polydienes have from the main chain by segments of different lengths.…”