Introduction of carboxyl groups into crosslinked polystyrene

Abstract

Carboxyl groups can be introduced into crosslinked polystyrene by a two step process involving 2-chlorobenzoylation and cleavage of the product using a mixture of potassium tert-butoxide and water. The reaction yields can be estimated easily by the change in weight of the resin and by chlorine analysis. Carboxyl groups can also be introduced via benzoylation. The previously described method of introducing carboxyl groups, in which crosslinked polystyrene is chloromethylated and the product oxidized to a formyl resin, which is then oxidized to a carboxyl resin, can be improved by using peracetic acid in methanesulphonic acid as the oxidant in the last step. ZUSAMMENFASSUNG:Carboxylgruppen konnen in vernetztes Polystyrol uber einen ZweistufenprozeD durch 2-Chlorbenzoylierung und Aufspaltung des Reaktionsproduktes mit einer Mischung von Kalium-tert-butoxid und Wasser eingefuhrt werden. Den Umsatz kann man durch die Gewichtsanderung des Harzes und durch Chloranalyse leicht abschatzen. Carboxylgruppen konnen auch durch Benzoylierung eingefuhrt werden. Das bereits beschriebene Verfahren, um Carboxylgruppen einzufiihren, indem man vernetztes Polystyrol chlormethyliert, das erhaltene Produkt zu einem Formylharz oxidiert und dieses Produkt zu einem Carboxylharz weiteroxidiert, kann durch die Verwendung von-Peressigsaure in Methansulfonsaure als Oxidationsmittel im letzten Schritt verbessert werden.

Oxidation of Stereo‐regular Poly(styrene‐co‐4‐methylstyrene) by Cobalt(II) Acetate Tetrahydrate/Sodium Bromide Catalyst

“…The polymer solutions were prepared by dissolving them in C 2 D 2 Cl 4 at 75°C. The styrene tacticity was determined from the (mm), (mr) and (rr) triad concentrations by the 13 Glass fiber (30 wt%) was used to reinforce the starting sPS-PMS copolymer and a 7.3% oxidized sample. Both composites were made by a Newbury injection molder equipped with a ASTM cluster mold.…”

“…The second method basically involved the use of Lewis acid (i.e. AlCl 3) to promote Friedel-Craft acylation, [13][14][15] followed by saponification to generate carboxylated PS and derivatives. This technique lies in its simplicity of execution and availability of the starting materials.…”

“…Cobalt catalyst (cobalt acetate tetrahydrate, Co(CH 3 CO 2 ) 2 .4H 2 O) was then applied to the resulting sPS-PMS to oxidize the benzylic methyl group to generate the oxidized product. In this report, the molecular micro-structure of the oxidized products was characterized by solution 13 C NMR. 15 Physical properties such as molecular weight and its distribution and thermal properties are confirmed by GPC, NMR and DSC.…”

Functionalization of Polystyrene with Cyclic Anhydrides and their Spectroscopic, Adhesive and Corrosive Characterizations

“…The synthesis of new polymeric materials can be carried out by either the polymerization of new monomers or the chemical modification of polymers with an appropriate technique (Gaylord et al, 1989;Harrison et al, 1975). During recent years, polymer chemists have increasingly focused on the need to maximize efficacy because of the widespread use of polymers in high physicomechanical materials and the interest in improving their performance, adhesion, and photosensitivity.…”

Characterization and dual functionalization of polystyrene with propionic anhydride and cyanate derivatives

“…Accordingly, it has become a promising material for various applications in the automotive, electronics, and packaging industries, too. 15,16 With the chemical modification, substances that have high molecular weights react chemically, like the low ones, and new kids of polymers can be synthesized. 3 However, PS without additional functional groups has limited properties such as thermal stability, mechanical strength, adhesion capability, corrosion resistance, and photosensitivity.…”