Abstract Poly( L ‐lactide) (PLA) was melt‐blended with four rubber components—ethylene–propylene copolymer, ethylene–acrylic rubber, acrylonitrile–butadiene (NBR), and isoprene (IR)—in an effort to toughen PLA. All the blend samples exhibited distinct phase separation. Amorphous PLA constituted a topologically continuous matrix in which particles were dispersed. According Izod impact testing, toughening achieved only when blended NBR, showed smallest particle size its samples. In agreement...

ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTThemoreversible Cross-Linking Rubber Using Supramolecular Hydrogen-Bonding NetworksKeisuke Chino and Makoto AshiuraView Author Information Research & Development Center, The Yokohama Rubber, Co. Ltd., 2-1 Oiwake, Hiratsuka, Kanagawa 254-8601, Japan Cite this: Macromolecules 2001, 34, 26, 9201–9204Publication Date (Web):November 10, 2001Publication History Received17 July 2001Published online10 November inissue 1 December...

A novel intrinsically stretchable ABA triblock copolymer can be synthesized where and B are poly(3-hexylthiophene) (P3HT) polyisobutylene (PIB) segments, respectively. The deformation of the self-assembled hierarchical nanostructure block thin film was clearly observed by grazing incidence small- wide-angle X-ray scattering.

The substituent effect on the polymerization of o-quinodimethanes generated by thermal isomerization benzocyclobutenes and reaction obtained polymer is described. Polymerizations 1-methoxybenzocyclobutene (1), 1-acetoxy benzocyclobutene (2), 1-hydroxybenzocyclobutene (3), 1-((trimethylsilyl)oxy)benzocyclobutene (4) as bearing electron-donating groups were examined. Although 2 3 did not afford any polymer, 1 4 in presence a radical initiator gave MeOH-insoluble (Mn = 5000−11000) moderate...

Abstract Thermoreversible crosslinking rubber (TRC-IR) was easily synthesized by modification of isoprene (IR) with maleic anhydride followed the addition 3-amino-1,2,4-triazole (ATA), in solid phase. The mechanical properties resulting were more similar to sulfur-vulcanized than general thermoplastic elastomers (ex. SEBS). Although tensile strength and elongation at break lower those a corresponding rubber, moduli as high sulfur-cured rubber. Re-molding TRC-IR could be repeated 10 times...

Abstract The first radical polymerization of 1‐methoxy‐ o ‐quinodimethane (2) generated by thermal ring‐opening isomerization 1‐methoxybenzocyclobutene (1) is described. 1 in the presence a initiator afforded an MeOH‐insoluble polymer (3) moderate yield at temperatures above 90°C. structure obtained consistent with polymerization. increased amount initiator. Radical copolymerization methyl acrylate was carried out. Treatment 3 acid gave poly(o‐phenylenevinylene), quantitatively.

The substituent effect on the radical polymerization of o-quinodimethanes, generated by thermal isomerization benzocyclobutenes, was investigated. Polymerizations three benzocyclobutenes bearing electron-withdrawing groups were studied, namely 1-cyanobenzocyclobutene (1), 1-chlorobenzocyclobutene (2), and 1-bromobenzocyclobutene (3). While polymerizations 2 3 did not afford any polymer, 1 afforded n-hexane-insoluble polymer(Mn = 5000) in moderate yields at temperatures above 120°C. structure...

Bezocyclobutenes are useful compounds as precursors to o-quinodimethanes, which highly reactive dienes. However, the thermal isomerization temperatures(IT) of substituted benzocyclobutenes o-quinodimethanes have not been predictable based on simple substituent effect. In this paper, we provide a method predict IT by calculation activation energies using semi-empirical molecular orbital calculation. ITs various were estimated method. Keywords: Bezocyclobutene, o-quinodimethane, temperature,...

Abstract 4‐Vinylbenzocyclobutene ( 1 ) was prepared by the nickel‐catalyzed coupling reaction of 4‐bromobenzocyclobutene with vinylbromide in 70% yield. Radical homopolymerization at 60°C for 24 h afforded poly(4 vinylbenzocyclobutene) [poly( )] 89% yield and radical copolymerizations styrene (St) or methyl methacrylate (MMA) were carried out to obtain corresponding copolymers. The Q = 1.07, e 0.046. As a model polymer poly( poly(4‐vinylbenzocyclobutene‐co‐styrene) [copoly( ‐St)]...

Abstract The ionic polymerization of substituted o ‐quinodimethanes via thermal isomerization benzocyclobutenes is described. In the cationic polymerizations 1‐methoxy‐ ‐quinodimethane in presence various initiators at 110 °C for 12 h, chain transfer reactions also considerably underwent besides polymerization. Meanwhile, 1‐trimethylsilyloxy‐ under same conditions gave good yields corresponding polymer. Anionic 1‐cyano‐ anionic such as n ‐BuLi or t ‐BuOK were performed temperatures h. Good...

Abstract We investigated improvement of workability (viscosity), storage stability, and curing ability thiirane resin for adhesive applications. The viscosity bisphenol‐F was lower than that bisphenol‐A resin, especially at low temperatures, thus improving ease handling. Addition diphenyl decyl phosphite improved its stability to a level similar epoxy resin. increased three times faster by adding 2,4,6‐tris(dimethylaminomethyl)phenol (DMP‐30) as tertiary amine. In applications this new civil...

A high-performance elastomer was obtained by a multinetworking system of covalent bond, hydrogen and clay plane bond. By taking advantage the characteristics each cross-linking, thermoplastic shows excellent compression set resistance, good flowability, high tensile properties. The bond gives flowability due to cleavage under heating. contributes low prevention polymer chain flow. Moreover, affects properties de-localization entire cross-link increase hysteresis energy between surface other...

The detailed morphological studies of poly(3-hexylthiophene)(P3HT)-b-polyisobutylene(PIB)-b-P3HT:P3HT blend thin films by grazing incidence X-ray scattering (GIXS) were reported. results GIXS experiments indicated the formation phase separation between P3HT and PIB domains even after blending homopolymer below 30 wt%. change in d-spacing values phase-separated under strains was suppressed increasing weight ratio homopolymer, probably due to disruption microphase separation. induced edge-on...

1-Benzocyclobutenyl vinyl ether (1) was easily prepared by the elimination reaction of hydrogen bromide from 1-benzocyclobutenyl 1-bromoethyl obtained 1-bromobenzocyclobutene and ethylene glycol via two steps in a good yield. Cationic polymerizations 1 carried out at −78°C for 2 h toluene presence BF3OEt2 as an initiator to give quantitatively corresponding polymers (2) white solids. As model polymer with dienophiles, Diels–Alder reactions 1-methoxybenzocyclobutene maleic anhydride (MA)...

Abstract Reaction of 1-trimethylsilyloxybenzocyclobutene(1) with carbonyl compounds catalyzed by tris(dimethylamino)sulfur (trimethylsilyl)difluoride (TASF) at room temperature gave 1-isochromanol derivatives as corresponding hetero Diels-Alder adducts in good yields.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRadical Polymerization of .alpha.-Methylenebenzocyclobutene, A Cyclic Analog .alpha.-MethylstyreneKeisuke Chino, Toshikazu Takata, and Takeshi EndoCite this: Macromolecules 1995, 28, 17, 5947–5950Publication Date (Print):August 1, 1995Publication History Published online1 May 2002Published inissue 1 August 1995https://pubs.acs.org/doi/10.1021/ma00121a035https://doi.org/10.1021/ma00121a035research-articleACS PublicationsRequest reuse...

Thermoreversible crosslinking rubber (TRC-IR) was easily synthesized by modification of isoprene (IR) with maleic anhydride followed the addition 3-amino-1, 2, 4-triazole(ATA), in solid phase. The mechanical properties resulting were more similar to sulfur-vulcanized than general thermoplastic elastomers (ex. SEBS). Although tensile strength and elongation at break lower those a corresponding sulfurcured rubber, moduli as high sulfur-cured rubber. Re-forming TRC-IR could be repeated 10 times...

In general, since rubber has a weak interaction between molecular chains, if it is not crosslinked, will flow and cannot withstand actual use. Covalent crosslinked high mechanical properties due to the strong bonding force of crosslinking, but difficult be reshaped recycled because difficulty cleave crosslink. On other hand, thermoplastic elastomers use physical interactions chains (physical crosslinking) suppress fluidity express properties. Therefore, although can by disconnecting...

Abstract A novel group transfer polymerization via hetero‐Diels‐Alder reaction is described. When 1‐trimethylsiloxybenzocyclobutene ( 1 ) was treated with a catalytic amount of p ‐anisaldehyde (4‐methoxybenzaldehyde) and TASF (tris(dimethylamino)sulfonium difluorotrimethylsilanide) at room temperature for 0.5 h, poly[1,2‐phenylene‐1‐(trimethylsiloxy)ethylene] obtained quantitatively. The number‐average molecular weight the polymer M̄ n = 2000 distribution narrow (ratio weight‐to weights w...

The radical polymerization behavior of 1-cyano-o-quinodimethane generated by thermal isomerization 1-cyanobenzocyclobutene in the presence 2,2,6,6-tetramethylpiperidine-N-oxide (TEMPO) and block copolymerization obtained polymer with styrene are described. was carried out a sealed tube at temperatures ranging from 100 to 150 °C for 24 h di-tert-butyl peroxide (DTBP) as initiator two equivalents TEMPO trapping agent propagation end obtain hexane-insoluble above 130 °C. Polymerization 5 mol %...

Thermoreversible Hydrogen-bond crosslinking isoprene rubber (THC-IR) was synthesized by modification of (IR) with maleic anhydride followed the addition 3-amino-1, 2, 4-triazole(ATA), in solid phase. The mechanical properties resulting were more similar to sulfur-vulcanized than general thermoplastic elastomers (ex. SEBS). Although tensile strength and elongation at break lower those a corresponding sulfur-cured rubber, moduli as high rubber. Reforming could be repeated 10 times without...