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Flexible Films (flexible + film)
Selected AbstractsBenzoxazine containing polyester thermosets with improved adhesion and flexibilityJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 19 2010Alev Tuzun Abstract High molecular weight polyesters containing thermally curable benzoxazine units in the main chain have been synthesized. For this purpose, first the diol functional monomer is synthesized through the Mannich and subsequent ring closure reactions of bisphenol-A, paraformaldehyde, and 5-amino-1-pentanol. Polycondensation of the resulting benzoxazine and pyromellitic dianhydride or 4-4,-(hexafluoroisopropylidene) diphatalic anhydride with or without dibutyltin laurate yielded the corresponding polyesters with the molecular weights between 5800 and 7000 Da. The structures of the precursor diol monomer and the resulting polyesters are confirmed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy analysis. Curing behavior of both the monomer and polymers has also been studied by differential scanning calorimetry. Flexible films of the polyesters were obtained by solvent casting on tin plates and crosslinked by heating in the absence of any catalyst. The cured films exhibited high flexibility and adhesion on the tin plates as determined by ASTM and DIN tests. Thermal properties of the cured polymers were also investigated by thermogravimetric analysis (TGA). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4279,4284, 2010 [source] Novel Soluble Polyimide Containing 4- tert- Butyltoluene Moiety: Synthesis and CharacterizationCHINESE JOURNAL OF CHEMISTRY, Issue 11 2009Chenyi Wang Abstract Based on the synthesis of a rigid aromatic diamine, ,,, -bis(4-aminophenyl)-4-(t- butyl)toluene (1), a novel polyimide (PI) 3 was prepared from this diamine monomer and 4,4,-oxydiphthalic dianhydride via a one-step high-temperature polycondensation. FT-IR, 1H NMR and elemental analysis were used to investigate the chemical structures of 1 and 3. The results confirmed that they agreed with the proposed structures for both 1 and 3 completely. The obtained PI 3 showed excellent solubility in most common solvents such as N -methyl-2-pyrrolidinone, N,N -dimethylacetamide, N,N -dimethylformamide, chloroform, dichloromethane and tetrahydrofuran. The resulting strong and flexible film exhibited high thermal stability with the glass transition temperature at 317°C and the temperature at 10% weight loss beyond 519°C in both air and nitrogen atmospheres. Moreover, the film also showed high optical transparency, low dielectric constant (3.13 at 1 MHz), low water absorption (0.40%) and hydrophobic character. [source] Flexible Silk,Inorganic Nanocomposites: From Transparent to Highly ReflectiveADVANCED FUNCTIONAL MATERIALS, Issue 5 2010Eugenia Kharlampieva Abstract A novel type of all-natural, biocompatible, and very robust nanoscale free-standing biohybrids are reported. They are obtained by integrating a silk fibroin matrix with functional inorganic nanoplatelets using a spin-assisted layer-by-layer assembly. The organized assembly of the silk fibroin with clay (montmorillonite) nanosheets results in highly transparent nanoscale films with significantly enhanced mechanical properties, including strength, toughness, and elastic modulus, as compared to those for the pristine silk nanomaterials. Moreover, replacing clay nanoplatelets with a highly reflective Langmuir monolayer of densely packed silver nanoplates causes a similar enhancement of the mechanical properties, but in contrast to the materials above, highly reflective, mirror-like, nanoscale flexible films are created. This strategy offers a new perspective for the fabrication of robust all-natural flexible nanocomposites with exceptional mechanical properties important for biomedical applications, such as reinforced tissue engineering. On the other hand, the ability to convert silk-based nanoscale films into mirror-like biocompatible flexible films can be intriguing for prospective photonics and optical exploitation of these nanobiohybrids. [source] Synthesis and properties of novel organosoluble aromatic poly(ether ketone)s containing pendant methyl groups and sulfone linkagesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2008Shou-Ri Sheng Abstract Several novel aromatic poly(ether ketone)s containing pendant methyl groups and sulfone linkages with inherent viscosities of 0.62,0.65 dL/g were prepared from 2-methyldiphenylether and 3-methyldiphenylether with 4,4,-bis(4-chloroformylphenoxy)diphenylsulfone and 4,4,-bis (3-chloroformylphenoxy)diphenylsulfone by electrophilic Friedel,Crafts acylation in the presence of N,N -dimethylformamide with anhydrous AlCl3 as a catalyst in 1,2-dichloroethane. These polymers, having weight-average molecular weights in the range of 57,000,71,000, were all amorphous and showed high glass-transition temperatures ranging from 160.5 to 167°C, excellent thermal stability at temperatures over 450°C in air or nitrogen, high char yields of 52,57% in nitrogen, and good solubility in CHCl3 and polar solvents such as N,N -dimethylformamide, dimethyl sulfoxide, and N -methyl-2-pyrrolidone at room temperature. All the polymers formed transparent, strong, and flexible films, with tensile strengths of 84.6,90.4 MPa, Young's moduli of 2.33,2.71 GPa, and elongations at break of 26.1,27.4%. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Plasticizer Effect on Grease Barrier and Color Properties of Whey-protein Coatings on PaperboardJOURNAL OF FOOD SCIENCE, Issue 1 2003S.-Y. Lin ABSTRACT Whey protein concentrates with ,80% protein (WPC-80) plasticized with 0.64 M glycerol or sucrose, or with 0.34 or 0.64 M sorbitol or polyethylene glycol (PEG) 200, produced flexible films. WPC-80 with hydrolyzed lactose required addition of less sucrose to produce flexible films. WPC-80 films formed as coatings on paperboard gave a grease barrier comparable to WPI film-coatings. Long-term ambient storage of WPC-80 coated paperboard indicated that the use of sucrose as plasticizer imparted good grease resistance and minimized plasticizer migration. [source] Novel thermally stable poly(amine hydrazide)s and poly(amine-1,3,4-oxadiazole)s for luminescent and electrochromic materialsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2005Guey-Sheng Liou Abstract We describe the preparation, characterization, and luminescence of four novel electrochromic aromatic poly(amine hydrazide)s containing main-chain triphenylamine units with or without a para-substituted N,N -diphenylamino group on the pendent phenyl ring. These polymers were prepared from either 4,4,-dicarboxy-4,- N,N -diphenylaminotriphenylamine or 4,4,-dicarboxytriphenylamine and the respective aromatic dihydrazide monomers via a direct phosphorylation polycondensation reaction. All the poly(amine hydrazide)s were amorphous and readily soluble in many common organic solvents and could be solution-cast into transparent and flexible films with good mechanical properties. These poly(amine hydrazide)s exhibited strong ultraviolet,visible absorption bands at 346,348 nm in N -methyl-2-pyrrolidone (NMP) solutions. Their photoluminescence spectra in NMP solutions or as cast films showed maximum bands around 508,544 and 448,487 nm in the green and blue region for the two series of polymers. The hole-transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. All obtained poly(amine hydrazide)s and poly(amine-1,3,4-oxadiazole)s exhibited two reversible oxidation redox couples at 0.8 and 1.24 V vs. Ag/AgCl in acetonitrile solution and revealed excellent stability of electrochromic characteristics, changing color from original pale yellow to green and then to blue at electrode potentials of 0.87 and 1.24 V, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3245,3256, 2005 [source] Novel family of triphenylamine-containing, hole-transporting, amorphous, aromatic polyamides with stable electrochromic propertiesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2005Tzy-Hsiang Su Abstract We report the preparation and characterization of a series of novel electrochromic, aromatic poly(amine amide)s with pendent triphenylamine units. The synthesis proceeded via direct phosphorylation polycondensation between a novel diamine, N,N -bis(4-aminophenyl)- N,,N,-diphenyl-1,4-phenylenediamine, and various aromatic dicarboxylic acids. All the poly(amine amide)s were amorphous and readily soluble in many common organic solvents and could be solution-cast into transparent, tough, and flexible films with good mechanical properties. They exhibited good thermal stability and 10% weight-loss temperatures above 540 °C. Their glass-transition temperatures were 263,290 °C. These polymers in N -methyl-2-pyrrolidinone solutions exhibited strong ultraviolet,visible absorption peaks at 307,358 nm and photoluminescence peaks around 532,590 nm in the green region. The hole-transporting and electrochromic properties were studied with electrochemical and spectroelectrochemical methods. Cyclic voltammograms of poly(amine amide) films prepared by the casting of polymer solutions onto an indium tin oxide coated glass substrate exhibited two reversible oxidation redox couples at 0.65 and 1.03 V versus Ag/AgCl in an acetonitrile solution. All the poly(amine amide)s showed excellent stability with respect to their electrochromic characteristics; the color of the films changed from pale yellow to green and then blue at 0.85 and 1.25 V, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2085,2098, 2005 [source] Synthesis and characterization of phthalazinone containing poly(arylene ether)s via a novel N,C coupling reactionJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2003S. J. Wang Abstract High-molecular-weight poly(phthalazinone)s with very high glass-transition temperatures (Tg's) were synthesized via a novel N,C coupling reaction. New bisphthalazinone monomers (7a,e) were synthesized from 2-(4-chlorobenzoyl) phthalic acid in two steps. Poly(phthalazinone)s, having inherent viscosities in the range of 0.34,0.91 dL/g, were prepared by the reaction of the bis(phthalazinone) monomers with an activated aryl halide in a dipolar aprotic solvent in the presence of potassium carbonate. The poly(phthalazinone)s exhibited Tg's greater than 230 °C. polymer 8b synthesized from diphenyl biphenol and bis(4-flurophenyl) sulfone demonstrated the highest Tg of 297 °C. Thermal stabilities of the poly(phthalazinone)s were determined by thermogravimetric analysis. All the poly(phthalazinone)s showed a similar pattern of decomposition with no weight loss below 450 °C in nitrogen. The temperatures of 5% weight loss were observed to be about 500 °C. The poly(phthalazinone)s containing 4,4,-isopropylidenediphenol and 4,4,-(hexafluoroisopropylidene) diphenol and diphenyl ether linkage were soluble in chlorinated solvents such as chloroform. Other poly-(phthalazinone)s were soluble in dipolar aprotic solvents such as N,N,-dimethylacetamide. The soluble poly(phthalazinone)s can be cast as flexible films from solution. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2481,2490, 2003 [source] Synthesis and characterization of novel soluble triphenylamine-containing aromatic polyamides based on N,N,-bis(4-aminophenyl)- N,N,-diphenyl-1,4-phenylenediamineJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2002Guey-Sheng Liou Abstract A new triphenylamine-containing aromatic diamine, N, N,-bis(4-aminophenyl)- N, N,-diphenyl-1,4-phenylenediamine, was prepared by the condensation of N,N,-diphenyl-1,4-phenylenediamine with 4-fluoronitrobenzene, followed by catalytic reduction. A series of novel aromatic polyamides with triphenylamine units were prepared from the diamine and various aromatic dicarboxylic acids or their diacid chlorides via the direct phosphorylation polycondensation or low-temperature solution polycondensation. All the polyamides were amorphous and readily soluble in many organic solvents such as N, N -dimethylacetamide and N -methyl-2-pyrrolidone. These polymers could be solution cast into transparent, tough, and flexible films with good mechanical properties. They had useful levels of thermal stability associated with relatively high glass-transition temperatures (257,287 °C), 10% weight-loss temperatures in excess of 550 °C, and char yields at 800 °C in nitrogen higher than 72%. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2810,2818, 2002 [source] Preparation of aromatic polyimides highly soluble in conventional solventsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 2 2002Wei Huang Abstract Several highly soluble polyimides were synthesized from various aromatic tetracarboxylic dianhydrides and an aromatic diamine containing tert -butyl pendent groups [4,4,-methylenebis(2- tert -butylaniline)]. All the polyimides showed excellent solubility in common solvents such as chloroform, tetrahydrofuran, and dioxane at room temperature. The number-average molecular weight ranged from 3.6 × 104 to 1.3 × 105 according to gel permeation chromatography relative to a polystyrene standard, and the polydispersity index was between 1.9 and 2.5. The glass-transition temperatures of the resulting polyimides ranged from 213 to 325 °C, as measured by differential scanning calorimetry, and little weight loss was observed up to 450 °C in N2 by thermogravimetric analysis. These experimental data indicated that the tert -butyl pendent groups reduced the interactions among polymer chains to improve their solubility in organic solvents without the loss of thermal stability. Transparent and flexible films of these polyimides were obtained via casting from solution. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 229,234, 2002 [source] Organosoluble and transparent polyimides derived from alicyclic dianhydride and aromatic diaminesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 1 2002J. G. Liu Abstract Organosoluble polyimides were synthesized with the alicyclic dianhydride 1,8-dimethylbicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and aromatic diamines. The polyimides possessed good solubility both in strong dipolar solvents and in common solvents; the thermal decomposition temperature of the polyimides exceeded 420 °C. Strong and flexible films of the polyimides, with the cutoff of ultraviolet,visible absorption lower than 310,320 nm, exhibited good features as the alignment layers for nematic liquid crystals with pretilt angles of 1.5,2.9°. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 110,119, 2002 [source] Liquid Crystalline Ordering and Charge Transport in Semiconducting MaterialsMACROMOLECULAR RAPID COMMUNICATIONS, Issue 14 2009Wojciech Pisula Abstract Organic semiconducting materials offer the advantage of solution processability into flexible films. In most cases, their drawback is based on their low charge carrier mobility, which is directly related to the packing of the molecules both on local (amorphous versus crystalline) and on macroscopic (grain boundaries) length scales. Liquid crystalline ordering offers the possibility of circumventing this problem. An advanced concept comprises: i) the application of materials with different liquid crystalline phases, ii) the orientation of a low viscosity high temperature phase, and, iii) the transfer of the macroscopic orientation during cooling to a highly ordered (at best, crystalline-like) phase at room temperature. At the same time, the desired orientation for the application (OLED or field-effect transistor) can be obtained. This review presents the use of molecules with discotic, calamitic and sanidic phases and discusses the sensitivity of the phases with regard to defects depending on the dimensionality of the ordered structure (columns: 1D, smectic layers and sanidic phases: 2D). It presents ways to systematically improve charge carrier mobility by proper variation of the electronic and steric (packing) structure of the constituting molecules and to reach charge carrier mobilities that are close to and comparable to amorphous silicon, with values of 0.1 to 0.7,cm2,·,V,1,·,s,1. In this context, the significance of cross-linking to stabilize the orientation and liquid crystalline behavior of inorganic/organic hybrids is also discussed. [source] | |||||||||||||