Synthesis of ABA Triblock Copolymers via a Tandem Ring-Opening Metathesis Polymerization:  Atom Transfer Radical Polymerization Approach

Abstract

The synthesis of poly(styrene)-b-poly(butadiene)-b-poly(styrene) (SBS) and poly(methyl methacrylate)-b-poly(butadiene)-b-poly(methyl methacrylate) (MBM) triblock copolymers with poly-(butadiene) (PBD) segments containing 100% 1,4-microstructure is described. Bis(allyl chloride) and bis-(2-bromopropionate) terminated telechelic PBD's were synthesized by the ring-opening metathesis polymerization (ROMP) of 1,5-cyclooctadiene in the presence of the corresponding difunctional chain transfer agents. These telechelic PBDs were subsequently used as difunctional macroinitiators for the heterogeneous atom transfer radical polymerization (ATRP) of styrene and methyl methacrylate to form SBS and MBM triblock copolymers. Triblock structure was confirmed by selective PBD degradation. In addition, the tandem ROMP-ATRP approach was successfully extended to a "one-pot" synthesis.

A Modular Approach toward Block Copolymers

“…Additionally, this methodology allows for complete control of the molecular weight of the desired polymer through the control of the CTA to monomer ratio thereby allowing for unprecedented control over end-group functionalization, homopolymer properties, and ultimately block copolymer properties. [27][28][29][30] Following the CTA-based preparation of homopolymers possessing complementary recognition units at the chain termini, rapid self-assembly through the exploitation of noncovalent interactions allows for rapid preparation of a large variety of block copolymers.…”

“…[26] Most CTAs reported in the literature are based on cis-2-butenediol derivatives. [27][28][29][30] However, we hypothesized that the large terminal recognition units employed in our investigations would be sterically demanding requiring a long alkyl spacer situated between the olefin and recognition unit. Accordingly, a series of novel CTAs (6-11) containing nonylalkyl spacers were chosen as synthetic targets.…”

Block Copolymers by the Conversion of Living Lithium Initiated Anionic Polymerization into Living Ruthenium ROMP

“…Previously reported methods for synthesizing block copolymers by combining well-defined ruthenium initiated ROMP and PS, have produced materials that possess a rather broad molecular weight distribution. 28,13 For instance the ROMP of norbornene derivatives b a initiated by ruthenium initiators was used to create macroinitiators that initiated the ATRP of styrene, resulting in the synthesis of block copolymers of styrene with a PDI of 2.70. 29 The molecular weight distributions of the block copolymer synthesized with our methodology thus compare very favourably with PS-PNB block copolymers synthesized via other routes.…”

Polyisobutylene-b -Poly(N,N -diethylacrylamide) well-defined amphiphilic diblock copolymer: Synthesis and thermo-responsive phase behavior

“…[6][7][8][9] The "sequential feeding" method is the simplest way to gain PIB-based block copolymer. Because PIB can only be achieved by living cationic polymerization, monomers suitable for living cationic polymerization including styrene 10,11 and alkyl vinyl ether 12 can be chosen as the second monomer.…”