Synthesis and Characterization of Stereoregular Ethylene-Vinyl Alcohol Copolymers Made by Ring-Opening Metathesis Polymerization

Copolymers of ethylene and ethyl acrylate have been widely used as commodity materials in many fields. In this article, a general synthetic strategy toward fine tuning the ethyl acrylate content and facile control over the monomer sequence regularity of this important type of copolymer via acyclic diene metathesis (ADMET) polymerization followed by hydrogenation is demonstrated. Three structurally symmetric diene monomers (M1–M3) were synthesized in good yields via a three‐step synthetic approach; each of the monomers contains two tail‐to‐tail linked ethyl acrylate units connected to the terminal alkenes by a methylene spacer with specific length. ADMET homopolymerization of M1–M3 and copolymerization of these monomers with 1,9‐decadiene were conducted, and after hydrogenation, a family of periodic and random copolymers of ethylene and ethyl acrylate were obtained. All the polymer samples were characterized by gel permeation chromatography and nuclear magnetic resonance, and the thermal properties of the saturated copolymers were investigated with thermal gravimetric analysis and differential scanning calorimetry. The glass transition and melting behaviors of this family of ethylene and ethyl acrylate copolymers were found to be dependent on the ethyl acrylate content and the primary structure regularity in copolymers. Copolymers with low ethyl acrylate content and periodic microstructures exhibited better crystallinity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2900–2909

Section: Resultssupporting

confidence: 86%

Ethylene–ethyl acrylate copolymers via ADMET polymerization: Effect of sequence distribution on thermal properties

Deng

et al. 2013

“…30%). We had thought that this may be due to lower ring strain, but calculations (similar to recent results) showed that monomer 13 had a ring strain energy of 13.8 kcal/mol while monosubstituted 6 has 11.8 kcal/mol (Table S3, Supporting Information). Interestingly though, 13 could be successfully polymerized under more typical ROMP conditions (strict oxygen‐free conditions in CH 2 Cl 2 with [ 13 ] = 0.6 M) and higher initiator loading ([ 13 ]:[ 7 ] = 50:1) to provide polymer 14 as a gummy solid by precipitation into methanol in 75% yield.…”

Section: Resultssupporting

confidence: 67%

“…This would potentially allow for the installation of 2 phosphorus moieties per monomer unit through 2 click reactions. Although there is less literature precedence for the use of such monomers (possibly due to lower ring strain), we were able to accomplish this. First, we subjected diol 11 (prepared from the same general starting materials as 4 , according to literature procedures) to the same conditions used for the preparation of ester 6 .…”

Section: Resultsmentioning

confidence: 92%

Ring opening metathesis polymerization (ROMP) and thio‐bromo “click” chemistry approach toward the preparation of flame‐retardant polymers

Grubb¹,

Carosio

Vasireddy³

et al. 2017

This contribution describes our recent efforts geared toward the use of a general, thio-bromo "click" reaction as a post-polymerization method for the preparation of flameresistant polymeric materials. a-bromo ester-containing polymers could easily be prepared using ROMP and a subsequent, facile thio-bromo click reaction was used for the installation of a phosphorus-moiety that was shown to impart flame-resistant/self-extinguishing properties to these polymers. The extent of their flame resistance was then ascertained by treating paper (previously coated with polymer) to standard burn tests as well as measuring the limiting oxygen index (LOI). V C 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 645-652

“…If a fully saturated backbone is desired, the polymer can be readily hydrogenated. The reader is directed to several excellent examples of olefin reduction following ROMP …”

Section: Considerations Of Ed‐rompmentioning

confidence: 99%

“…The reader is directed to several excellent examples of olefin reduction following ROMP. [54][55][56][57] ED-ROMP bears resemblance to ADMET in that the polymers obtained can share similar features with respect to the final polymer microstructure. In both cases, the structure of the repeating unit can be precisely programmed through the structure of the monomer.…”

Section: Considerations Of Ed-rompmentioning

confidence: 99%

Recent developments in entropy‐driven ring‐opening metathesis polymerization: Mechanistic considerations, unique functionality, and sequence control

Pearce

Foster

O’Reilly

2019

Entropy‐driven ROMP (ED‐ROMP) involves polymerization of olefin‐containing macrocyclic monomers under entropically favorable conditions. Macrocycles can be prepared from a variety of interesting molecules which, when polymerized, impart unique functionality to the resulting polymer backbone such as degradable linkages, biological moieties, crystallizable groups, or supramolecular hosts. In addition, the sequence of atoms in the cyclic monomer is preserved within the polymer repeating units, allowing for facile preparation of sequence‐defined polymers. In this review article, we consider how the mechanism of ROMP applies to ED polymerizations, how olefinic macrocycles are synthesized, and how polymerization conditions can be tuned to maximize conversion. Recent works in the past 10 years are highlighted, with emphasis on methods which can be employed to achieve fast polymerization kinetics and/or selective head‐to‐tail regiochemistry, thus improving polymerization control. ED‐ROMP, with its unique capability to produce polymers with well‐defined polymer backbone microstructure, represents an essential complement to other, well‐established, metathesis methodologies such as ROMP. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1621–1634