Chemical modification of polydienes in latex medium: Study of epoxidation and ring opening of oxiranes

Abstract

Referring to previous work carried out in organic solvents, a study of the action of nucleophilic reagents on epoxidized units of 1,4-epoxidized polyisoprene (synthetic polyisoprene or natural rubber) was performed in latex medium. Among the considered reagents, dialkylphosphate and ammonium diethyldithiophosphate demonstrated the ability to add under these reaction conditions on epoxidized units according to a SN2 substitution with an oxirane ring-opening mechanism. A systematic study was performed with dibutylphosphate that was shown to be very reactive. Grafting of phosphorated groups along polyisoprene chains was carried out via reaction of the acidic function (P-OH) of the phosphate with oxirane rings previously created on a 1,4-polyisoprene backbone. The prominent role of latex pH on the reaction was shown.

Optimization of the process of obtaining epoxidized natural rubber for the development of new composite materials on its basis

“…The epoxidation reaction is a random process and, therefore, the addition of oxygen to double bonds occurs randomly, distributed along the polymer molecule. The rate of epoxidation increases with increasing rubber concentration [3].…”

A structural study of epoxidized natural rubber (ENR‐50) ring opening under mild acidic condition

“…[5][6][7][8] Epoxide or oxirane is an ether in which the oxygen atom is incorporated into the C@C bond to form a three-membered ring. [12][13][14] ENR is a pH sensitive polymer and favors neutral pH. The carbons in an epoxide are very reactive electrophile thus able to react with a variety of nucleophile.…”

Synthesis of Fluorescent Polyisoprene Nanoparticles and their Uptake into Various Cells

“…The emulsion polymerization of isoprene is of interest since the obtained particles can be modified during or after polymerization; for example, copolymerization with dimethylaminoethyl methacrylate will result in a “hairy layer” on the particle surface 24. The remaining double bonds in the PI latex can also be used to functionalize the polymeric particles, for example, in a two‐step reaction, first by epoxidation and then by a subsequent S N 2 reaction 25, 26…”