Polyimides based on Poly(4-furanyl-butan-2-one)

1992 ◽  
Vol 4 (1) ◽  
pp. 19-33 ◽  
Author(s):  
Hasmukh S. Patel ◽  
Harshad D. Patel
Keyword(s):  
Thermal Stability ◽  
Acetic Anhydride ◽  
Mechanical Strength ◽  
Elemental Analysis ◽  
Diels Alder ◽  
Spectral Studies ◽  
Good Thermal Stability ◽  
Glass Reinforcement

Polyimides were prepared by Diels-Alder (DA) reaction of furfuralacetone (FAC) resin [poly(4-furanyl-butan-2-one)] with various bismaleimides. The DA reaction was carried out in tetrahydrofuran (THF) as solvent as well as in bulk, followed by aromatization of the tetrahydrophthalimide intermediates in the presence of acetic anhydride. All the polyimides were characterized by elemental analysis, IR spectral studies and thermogravimetry. The results show that polyimides based on FAC resin exhibit good thermal stability. Preliminary tests for glass reinforcement of the polyimides indicate that laminates with good mechanical strength can be prepared.

Polyimides Based on Furfuryl-Disulphide

1992 ◽  
Vol 4 (4) ◽  
pp. 237-246 ◽  
Author(s):  
Harshad D. Patel ◽  
Hasmukh S. Patel
Keyword(s):  
Thermal Stability ◽  
Acetic Anhydride ◽  
Mechanical Strength ◽  
Spectral Data ◽  
Preliminary Test ◽  
Diels Alder ◽  
Elemental Analyses ◽  
Glass Reinforcement

Poly (disulphido-imides) were prepared by Diels-Alder (DA) reaction of furfuryl-disulphide (FDS) with various bismaleimides. The DA reaction was carried out in xylene as solvent, as well as in bulk, followed by aromatization of terrahydrophthalimide intermediates in the presence of acetic anhydride. All the poly (disulphido-imide)s were characterized by elemental analyses, IR spectral data and thermogravimetry. The poly (disulphido-imide)s exhibit moderate thermal stability. Preliminary test for glass reinforcement of the poly (disulphido-imide) indicate that laminates with good mechanical strength can be obtained.

Synthesis Characterization and Glass Reinforcement of Poly(urethane-imide)s-III

1992 ◽  
Vol 4 (4) ◽  
pp. 247-257 ◽  
Author(s):  
Hasmukh S. Patel ◽  
Vipul J. Shah ◽  
Hemant S. Vyas
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Chemical Resistance ◽  
Fibre Composite ◽  
Diels Alder ◽  
Spectral Studies ◽  
Intermolecular Reaction ◽  
Glass Reinforcement ◽  
Glass Fibre Composite

Poly(urethane-imide)s (PUIs) were prepared by the intermolecular Diels-Alder (DA) reaction of methylenedi-4,1-phenylenebis(2-furanyl-methylcarb-amate) (MPBFC) with various bismaleimides. The DA reaction was carried out in 1,4-dioxane as solvent as well as in bulk, followed by aromatization of tetrahydro-phthalimide intermediates in the presence of acetic anhydride. All the polymers were characterized by elemental analysis, IR spectral studies and thermogravfmetry. The PUts exhibit moderate thermal stability. MPBFC and bismaleimides were polymerized (at 145 + 10 C) by an in situ DA intermolecular reaction into moderately thermally stable PUls-glass fibre composite (i.e. laminates) and were characterized by their chemical resistance and mechanical properties.

scholarly journals Efficient Synthesis of PVDF/PI Side-by-Side Bicomponent Nanofiber Membrane with Enhanced Mechanical Strength and Good Thermal Stability

Nanomaterials ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 39 ◽  
Author(s):  
Ming Cai ◽  
Hongwei He ◽  
Xiao Zhang ◽  
Xu Yan ◽  
Jianxin Li ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Thermal Stability ◽  
Mechanical Strength ◽  
Polyvinylidene Fluoride ◽  
Chemical Structure ◽  
Electrospun Fiber ◽  
Nanofiber Membrane ◽  
Application Range ◽  
Good Thermal Stability ◽  
Filtration Properties

Bicomponent composite fibers, due to their unique versatility, have attracted great attention in many fields, such as filtration, energy, and bioengineering. Herein, we efficiently fabricated polyvinylidene fluoride/polyimide (PVDF/PI) side-by-side bicomponent nanofibers based on electrospinning, which resulted in the synergism between PVDF and PI, and eventually obtained the effect of 1 + 1 > 2. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the morphology and chemical structure of nanofibers, indicating that a large number of side-by-side nanofibers were successfully prepared. Further, the thermal stability, mechanical strength, and filtration properties of PVDF/PI were carefully investigated. The results revealed that the bicomponent nanofibers possessed both good mechanical strength and remarkable thermal stability. Moreover, the mechanical properties of PVDF/ PI were strengthened by more than twice after the heat treatment (7.28 MPa at 25 °C, 15.49 MPa at 230 °C). Simultaneously, after the heat treatment at 230 °C for 30 min, the filtration efficiency of PVDF/PI membrane was maintained at about 95.45 ± 1.09%, and the pressure drop was relatively low. Therefore, the prepared PVDF/PI side-by-side bicomponent nanofibers have a favorable prospect of application in the field of medium- and high-temperature filtration, which further expands the application range of electrospun fiber membranes.

Conductive Polyaniline and Paper Reinforced Composites

2014 ◽  
Vol 556-562 ◽  
pp. 123-126
Author(s):  
Jin Hua Yan ◽  
Ren Mei Xu ◽  
Na Yun
Keyword(s):  
Thermal Stability ◽  
Mechanical Strength ◽  
Interfacial Polymerization ◽  
Lower Surface ◽  
Paper Substrate ◽  
Oh Groups ◽  
Good Thermal Stability ◽  
Conductive Composites ◽  
Novel Method ◽  
Conductive Polyaniline

A novel method of direct aniline multi-interfacial polymerization on paper substrate is introduced in this paper. Cellulose base papers with and without PAE reinforced were discussed. The PANI-paper composites after more than 3 polymerizations had much lower surface resistivity. Their mechanical strength and thermal stability were analyzed by tensile test and GTA. FTIR results explained that there was strong interaction between NH groups in aniline monomers and OH groups in fibers. Conductive composites made with PAE treated paper had both good thermal stability and good mechanical strength with high conductivity.

scholarly journals Synthesis, Characterization and Antibacterial Application of Copolymers Based on N,N-Dimethyl Acrylamide and Acrylic Acid

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6191
Author(s):  
Ulantay Nakan ◽  
Shayahati Bieerkehazhi ◽  
Balgyn Tolkyn ◽  
Grigoriy A. Mun ◽  
Mukhit Assanov ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Acrylic Acid ◽  
Elemental Analysis ◽  
Three Dimensional ◽  
Antimicrobial Properties ◽  
Chemical Properties ◽  
Ammonium Persulfate ◽  
Copolymer Composition ◽  
Good Thermal Stability ◽  
Linearization Methods

Hydrogel copolymers based on N,N-dimethyl acrylamide (DMA) and acrylic acid (AAc) were synthesized using a solution polymerization technique with different monomer ratios and ammonium persulfate as an initiator. This paper investigates the thermal stability, physical and chemical properties of the hydrogel copolymer. Testing includes Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and elemental analysis (CHNS). The copolymer composition was determined by elemental analysis, and the reactivity ratios of monomers were calculated through linearization methods such as Fineman–Ross (FR), inverted Fineman–Ross (IFR), Kelen–Tudos (KT) and Mayo–Lewis (ML). Good agreement was observed between the results of all four methods. The ratio of r1 and r2 were 0.38 (r1) and 1.45 (r2) (FR), 0.38 (r1) and 1.46 (r2) (IFR), 0.38 (r1) and 1.43 (r2) (KT), and 0.38 (r1) and 1.45 (r2) (ML). Hydrogel copolymers exhibited good thermal stability, and SEM showed three-dimensional porous structures. Antibiotic-free and antibiotic-loaded hydrogels demonstrated antimicrobial properties against both Gram-positive and Gram-negative bacteria. As the ratio of DMA in hydrogel copolymer increased, the activity of copolymer against bacteria enhanced. The results indicated that these hydrogels have the potential to be used as antibacterial materials.

scholarly journals Furan Functionalized Polyesters and Polyurethanes for Thermally Reversible Reactive Hotmelt Adhesives

2021 ◽  
Author(s):  
Laxmisha M. Sridhar ◽  
Andrew T. Slark ◽  
James A. Wilson
Keyword(s):  
Thermal Stability ◽  
Creep Resistance ◽  
Diels Alder ◽  
Melt Viscosity ◽  
Good Thermal Stability ◽  
Similar Performance ◽  
Cure Rates ◽  
Processing Properties ◽  
Good Creep Resistance ◽  
Hot Melt

New reactive hotmelt (RHM) adhesives based on thermally reversible Diels-Alder networks comprising multifunctional furan and maleimide prepolymers are described. The prepolymer mixture is easy to apply in the bulk from the melt and after application to the substrates, the adhesive undergoes polymerization at room temperature resulting in crosslinked bonds. Due to their thermoplastic nature and low melt viscosity at hot melt application temperatures, the adhesives provide processing properties similar to moisture cured polyurethanes (PUR). The technology is isocyanate-free and does not require moisture to initiate the crosslinking. Bonding and tensile properties of the RHM adhesive can be readily tuned by prepolymer design and provide cure rates similar to PUR adhesives. The Diels-Alder adhesives provide versatile adhesion to a variety of substrates and good creep resistance up to the retro temperature. The adhesives show good thermal stability during application and can be recycled multiple times by simple heating/cooling of the bonds providing similar performance. Several furan and maleimide prepolymers were scaled up to multi-Kg quantities to demonstrate the potential for industrial scalability. The results demonstrate that furan-maleimide reversible chemistry can be used for RHM application as a more sustainable alternative to conventional moisture curing PURs which tend to contain harmful residual isocyanate monomers.

Low Potential Electrochemical Polymerization of 1-Hydroxy-2-Methoxybenzene and Characterization of its Polymer

2012 ◽  
Vol 466-467 ◽  
pp. 170-175 ◽  
Author(s):  
Yao Huang ◽  
Mu Lin Ma ◽  
Hou Ting Liu ◽  
Jing Kun Xu ◽  
Ge Zhang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Conducting Polymer ◽  
Electrochemical Polymerization ◽  
Saturated Calomel Electrode ◽  
Spectral Studies ◽  
Excitation Wavelength ◽  
Nmr Studies ◽  
Good Thermal Stability ◽  
Blue Emitters

The electrochemical polymerization of 1-hydroxy-2-methoxybenzene (HMOB) was performed in boron trifuoride diethyl etherate (BFEE) and a novel conducting polymer poly(1-hydroxy-2-methoxybenzene) (PHMOB) was easily electrodeposited. The oxidation onset of HMOB was initiated at 0.97 V versus a saturated calomel electrode (SCE). PHMOB films obtained from BFEE showed good thermal stability. NMR studies showed that the polymerization of HMOB occurred at C4 and C5 position. Fluorescent spectral studies indicated that doped and dedoped PHMOB were good blue emitters, with the same excitation wavelength maximum of 348 nm.

scholarly journals Synthesis, Characterization and Biocidal Activity of Some Schiff Base Metal(II) Complexes

2020 ◽  
Vol 15 (3) ◽  
pp. 137-143
Keyword(s):  
Thermal Stability ◽  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Benzoic Acid ◽  
Elemental Analysis ◽  
Molar Conductance ◽  
Bidentate Ligand ◽  
Schiff Base Complexes ◽  
Good Thermal Stability ◽  
Carboxylate Oxygen

A Schiff base, 2-[4-(N,N-dimethylamino)benzylidene]benzoic acid has been synthesized by the condensation of 4-(N,N-dimethylamino)benzaldehyde and 2-amino-benzoic acid in 1:1 molar stoichiometry. The Schiff base complexes were synthesized from the chloride salts of Fe(II), Cu(II) and Zn(II) in ethanolic medium and elucidated by infrared spectroscopy, CHN elemental analysis, atomic absorption spectroscopy as well as conductivity and magnetic susceptibility measurements. The solubility and thermal stability were also determined. The metal(II) complexes are coloured solids that are soluble in DMF and DMSO. The melting point of the Schiff base was found to be 177 oC, while the complexes decompose within a temperature range of 202–261 oC suggestive of rather good thermal stability. The molar conductance values were low, indicating non-electrolytic nature of the complexes. Elemental analysis revealed that the stoichiometries of the synthesized complexes are of 1:2 metal-to-ligand ratio. All complexes were hydrated. The spectroscopic and magnetic susceptibility data revealed that the complexes possess four- coordinate distorted square planar stereochemistry, whereas the Schiff base behaves as monoanionic bidentate ligand with the nitrogen atom of the azomethine (C=N) and carboxylate oxygen (COO-) as donor sites. The Schiff base and its corresponding metal(II) complexes were assayed against a number of bacterial and fungal strains to evaluate their inhibitory potentials. All the complexes showed significant bactericidal and fungicidal activities against the tested organisms.

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