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Laminated film composite was fabricated by stacking the surface-modified poly(ethylene terephthalate) films using the initiated chemical vapor deposition (iCVD) method, with a ultraviolet (UV)-curable methacrylate-polyhedral oligomeric silsesquioxane (POSS) inorganic polymer interlayer binder to develop an alternative glass material. The 11-layered PET film/POSS composites were consolidated by UV exposure, and it increased modulus and maintained transmittance and haze.
In this paper, we have provided the first conclusive evidence that the Ni particle dispersed poly(methylmethacrylate) (PMMA) composites, which do not exhibit melting phenomenon, exhibit the positive temperature coefficient (PTC) effect when Ni content were 20 and 25vol.%. In particular, the composite with Ni content of 25vol.% exhibited PTC effect comparable to that of composites composed of crystalline polymer, and it demonstrated conductor/insulator transition. We assumed that these composites have few conductive paths, and so disconnection of conductive path occurred from slight volume expansion of PMMA by temperature rising.
STEP Isodiametric design space based deposition of polymeric micro/nanofibers in hierarchical multi-layer assemblies with control on fiber diameter, spacing and orientation.
A number of biomaterials have been proposed, including hydrophilic, phase-separated and zwitterionic polymers. It has not been clearly elucidated which mechanisms are responsible for biocompatibility on a molecular level. Water interactions have been recognized as a fundamental part of the biological response to contact with biomaterials. We have proposed the ‘intermediate water’ concept; the water exhibited both clear peak for cold crystallization in differential scanning calorimetry chart and a strong peak at 3400 cm−1 in a time-resolved infrared spectrum. We found the localized hydration structure consisting of the three hydrated water in poly(2-methoxyethyl acrylate) (PMEA).
The electrostatic self-assembly and covalent fixation (ESA-CF) process, in conjunction with click chemistry and olefin metathesis, was used to construct selectively a variety of unprecedented polymer architectures, such as manacle-shaped and tandem multicycles, as well as doubly fused tricyclic and triply fused tetracyclic topologies. Moreover, the self-assembly of a cyclic amphiphilic block copolymer, which was prepared by intramolecular metathesis, produced a micelle with an approximately 50 °C increase in thermal stability compared with the one from the linear prepolymer. Single-molecule spectroscopic studies also revealed different diffusion modes for cyclic and linear polymers.
Addition and ring-opening metathesis polymerizations of new monomers (Me3Si- and Me3Ge-substituted tricyclononene and tricyclononadienes) were carried out on Pd- or Ni-catalyst systems and Grubbs first-generation catalyst, respectively. New addition polymers were obtained with good yields up to 70% and molecular weight (Mw) up to 5.6 × 105. The yields of the first obtained metathesis polymers were higher than 80% and Mw were up to 8.8 × 105. It was shown that the novel addition polymer poly[(3-trimethylgermyl)tricyclononene-7] possesses high gas-transport parameters and solubility-controlled permeation of gaseous hydrocarbons.
Ab initio statistical mechanics based on the rotational isomeric state scheme and molecular orbital calculations has been applied to poly((R)-3-hydroxybutyrate)(PHB) to elucidate its conformational characteristics and configurational properties. This article presents fully consistent interpretations on its bond conformations, solution properties, crystal structure, thermal properties and interactions with a PHB depolymerase in terms of the conformational characteristics.
Composite polyether electrolytes filled with oriented MMT layers in perpendicular (M⊥) or parallel (M//) to the film surface were successfully obtained by the application of strong magnetic field. The ionic conductivity of the M⊥ composite with 5 wt% of Li-MMT was 1.2 × 10−5 S cm−1 at 30 °C, and the value was more than six times greater than that of the original electrolyte (PMEO10LiClO4). We concluded that the ionic migration on the layer of oriented MMT has a crucial role to increase the conductivity with lower activation energy.
A series of maleimide–thiophene copolymers presenting pendent 2-hydroxyethyl and 6-hydroxyhexyl units were synthesized. The maleimide–thiophene copolymers containing different contents of OH groups were then reacted with 3,3′-dimethoxy-4,4′-biphenylene diisocyanate in solution to form the interchain-linked polymers. The photovoltaic performances of the PSCs incorporating the interchain-linked copolymers were superior to those of the corresponding PSCs based on the OH-containing copolymers.
4,4′-Bismaleimidediphenylmethane (BMI) was cured finally at 250 °C with cardanol (CD) or CD novolac (CDN) prepared by the reaction of CD and paraformaldehyde with CD/maleimide unit ratios 1/2, 1/4 and 1/6. The obtained cured resins with CD/maleimide ratio lower than 1/2 did not show glass transition until 300°C and had 5% weight loss temperature higher than 450°C. The curing mechanism was elucidated by means of the proton nuclear magnetic resonance (1H-NMR) and Fourier transform infrared spectroscopy (FTIR) analyses of the model reaction products of CD and N-phenylmaleimide (PMI) and the cured resins.
Bis-pyrrolidone-type monomers (obtained from itaconic acid, which is a renewable chemical identified in the top 12 value-added chemicals from biomass) with alkylidene spacers of variable size were synthesized and polycondensed with various diamines. The resulting polycondensates were used as compatibilizers to improve interfacial adhesion in poly (butylene succinate) (PBS)/plasticized starch blends. The interfacial adhesion between PBS and plasticized starch was improved using these polycondensates.
Pentaerythritol-zinc (Penzinc) has been synthesized and its thermal stability, especially its synergism with β-diketone and calcium stearate, was characterized. Experimental results show that PVC stabilized with complex of Penzinc and β-diketone has an excellent initial color and long-term thermal stability. Moreover, the thermal stability mechanism of Penzinc and β-diketone are also discussed with the help of quantum chemical calculations. Results indicate that both α-H atom of β-diketone and zinc atom of Penzinc, having low electron density, can easily react with labile chloride atom of PVC, which has high electron density.