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The footprints of a macromolecular synthetic chemist were left on the sands of time. Novel anionic addition polymerization of fluorinated vinyl monomers, which generally show poor homopolymerization reactivity, has been developed. Anionic polyaddition has been achieved by the double Michael addition of bis(2-trifluoromethylacrylate)s to active methylene compounds. Radical addition of fluorinated vinyl monomers with many organic compounds possessing carbon–hydrogen bonds has been accomplished and amplified to the polyaddition reaction to incorporate fluorinated vinyl monomers into polymer main chains. The facile carbon–carbon bond formation reactions have been accomplished by the aid of fluorine substituents.
Chiral itaconimides bearing amino-acid esters at side chain (MRII), such as phenylglycine-, phenylalanine- and leucine-methyl ester, were polymerized with organometal-chiral ligand complexes to obtain optically active polymers. The effects of the polymerization conditions on the optical activity and structure of poly(MRII)s were investigated with gel permeation chromatography, circular dichroism, specific rotation and 13C nuclear magnetic resonance measurements.
The polysilsesquioxane containing 3-aminopropyl and phenyl groups was used as the macroinitiator for the graft polymerization of 1,3-trimethylene carbonate and L-(-)-lactide. The ring-opening polymerizations of the monomers by the use of 1-trimethylsilylimidaozle catalyst proceeded effectively to afford the grafted polysilsesquioxanes. In the obtained polysilsesquioxanes, the effects of polysiloxane main chain on the thermal properties of the grafted polymers were observed.
A series of free-standing poly(1,12-bis(carbazolyl)dodecane-co-3,4-ethylenedioxythiophene) (P(2Cz-D-co-EDOT)) films with crosslinking structure were synthesized electrochemically from 1,12-bis(carbazolyl)dodecane and 3,4-ethylenedioxythiophene. The obtained P(2Cz-D-co-EDOT) films show good redox activity and high electrochemical stability. Compared with those of poly(1,12-bis(carbazolyl)dodecane) and poly(3,4-ethylenedioxythiophene), the mechanical properties, electrical conductivities, thermoelectric properties and thermal stability of as-formed copolymer films are all improved in varying degrees.
Poly (vinylidene fluoride) (PVdF) dissolved in organic solvents containing lithium tetrafluoroborate (LiBF4) forms stable gels when the solution is cooled to room temperature. This paper describes the effects of LiBF4 concentrations and gelation solvents on the gelation process and the structural morphology. Gel-melting temperatures (Tmg) increased with an increase in LiBF4 concentrations (C), indicating that PVdF gels in the presence of LiBF4 would have increased thermal stability.
Two dry processings, atmospheric pressure plasma jet exposure and ultraviolet excimer light irradiation, were carried out using poly(ethylene terephthalate) film. The wettability change in the poly(ethylene terephthalate) surface was recorded by the Wilhelmy technique. After the processings, the drastic decreases in the advancing and receding contact angles of water were observed. The advancing angle increased by rinsing with water or aging in air, whereas the receding one remained almost the same. The wettability behavior obtained was discussed on the basis of the X-ray photoelectron spectroscopy and atomic force microscopy data.
A mixture of acrylated epoxidized soybean oil (AESO) with N-carbobenzyloxy-L-isoleucylaminooctadecane (CIA) or (R)-12-hydroxystrearic acid (HSA) containing photoinitiators was heated to 130 °C and gradually cooled to room temperature to give a bio-based gelatinous material. The photocuring of the AESO/CIA gel afforded a supramolecular composite composed of crosslinked AESO (cAESO) and self-assembled CIA fibers, whereas HSA crystallized in case of the photocuring of the AESO/HSA gel. Tensile strength and modulus for cAESO/CIA increased with CIA content, whereas those of cAESO/HSA decreased with HSA content.
High-performance all-cellulose nanocomposite was made from canola straw as a low-value agricultural residue through a cheap and fast method of downsizing (grinding) followed by a short partial dissolution process (10 min) in N,N-dimethylacetamide/lithium chloride solvent.
Vegetable oil-modified hyperbranched polyster was developed and used as a matrix for the preparation of nanocomposites with 0–5 wt% organically modified montmorillonite by ex situ technique, which showed the potentiality as advanced materials.
Thermal-dependent six-membered cyclic anhydrides were formed in the Eudragit E and polyvinyl alcohol (PVA) copolymer via intramolecular ester condensation by using differential scanning calorimeter (DSC)-Fourier transform infrared microspectroscopy. The temperature for intramolecular ester condensation was started from 180 °C for Eudragit E, but from 167 °C for PVA copolymer. The amount of intramolecular anhydride formed in the film of Eudragit E was found to be higher than that formed in the film of PVA copolymer during the heating process.
