Hydroformylation of high polymers

Abstract

SynopsisA new class of polymeric materials has been prepared and subjected to preliminary These materials were obtained by hydroformylation of diene-based poly-evaluation. mers. The olefinic bonds were saturated and aldehyde groups attached:The extent of reaction may be varied a t will up to 100% double bond conversion. The properties of these polymers are dominated by the active aldehyde groups. One of the chief characteristics of simple aldehydes is their ability to polymerize forming mainly aldehyde trimers and tetramers. This same phenomenon has been shown to occur with polymeric aldehydes with consequent gel formation. The gelling tendency has been closely related to the aldehyde content per unit volume which may be conveniently varied by (1) the concentration of the initial polymer, (2) the degree of unsaturation in the polymer, and (3) the extent of double bond conversion. Any combination which gives a free aldehyde concentration in excess of 1 X 10-4 mole/ml. is very prone to gel. The loose gels can be readily reversed by conditions which depolymeriae aldehydes. The propensity of the aldehyde polymers to crosslink upon evaporation of the solvent was used to form films. These films were not discolored by ultraviolet light but under such treatment became quite brittle. The products may be stmabilked by conversion of the aldehyde groups to more stable derivative, in particular the acetal. The extent of acetal formation has been shown to be controlled by steric factors. Complete polyacetal formation was possible only when the aldehyde groups were well dispersed along the polymer chain. Certain aldehyde derivatives (metals, oximes) are thermoplastic. They soften at lower temperature than commercial plastics.

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

“…The hydroformylation of alkenes using syngas (carbon monoxide and hydrogen) is a well-known transformation that has been used for a long time in many industrial processes. The first application of this methodology for the introduction of formyl groups into olefinic polymers was reported in 1966 . The hydroformylation of different diene-based polymers was performed with the dicobalt octacarbonyl complex as catalyst, requiring harsh conditions.…”

“…The first application of this methodology for the introduction of formyl groups into olefinic polymers was reported in 1966. 33 The hydroformylation of different diene-based polymers was performed with the dicobalt octacarbonyl complex as catalyst, requiring harsh conditions. Complete conversions were achieved at 180 °C for 3 h, with an initial H 2 :CO pressure of 2400 psi (Scheme 5A).…”

Hydroformylation of high‐molecular‐weight cis‐1,4‐polybutadiene catalyzed by HRH(CO)(PPh3)3

“…The catalytic hydroformylation of unsaturated polymers is a process by which aldehyde groups are introduced into the backbone polymer by a treatment with H 2 and CO in the presence of a catalyst. The common catalyst generally used for this process is a Co or Rh complex 2–10. The most effective catalysts for the hydroformylation of CC are rhodium complexes.…”

“…Most studies of the hydroformylation of diene polymers, that is, polybutadiene (PBD) and poly(styrene butadiene) (SBR), were carried out in the presence of rhodium catalysts. However, the earliest study showed that the hydroformylation of 1,4‐PBD and high‐styrene SBR could be achieved at high pressures and temperatures with a cobalt catalyst,2 but there was considerable gel formation during this process. The first report of the use of HRh(CO)(PPh 3 ) 3 in the hydroformylation of a polypentenamer was by Sanui et al,3 and the reaction was carried out under moderate conditions with no gel formation.…”

Catalytic Hydrocarboxylation and Hydroesterification Reactions of 1,2-Polybutadiene

“…Functional polymers are generally prepared by the polymerization of monomers containing the desired functional groups. As these polymerizations are sometimes associated with potential problems, much attention has been paid to the development of the catalytic functionalization of diene-based elastomers. − The production of polymers with carboxylated backbones is of particular interest due to potential applications of such polymers in films and surface coating…”