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.

Cross-Linked Polyamides

2002 ◽  
Vol 10 (4) ◽  
pp. 315-324
Author(s):  
H.S. Patel ◽  
V.C. Patel
Keyword(s):  
Diels Alder ◽  
Spectral Studies ◽  
Reinforced Composites ◽  
Intermolecular Reaction ◽  
Glass Fibre Reinforced ◽  
Ft Ir ◽  
Glass Fibre Reinforced Composites ◽  
By Products ◽  
Fibre Reinforced Composites

Cross linked polyimides containing a s-triazine ring have been synthesized via the Diels-Alder intermolecular polymerization of 2,4,6-tris(2-furanyl methyl imino)-1,3,5-triazine with various bis(maleimide) compounds, followed by the aromatization of the corresponding Diels-Alder products. All the poly(imino- s-triazine imide)s were characterized by elemental analysis, FT-IR spectral studies and thermogravimetry. Glass fibre reinforced composites were prepared via an in-situ Diels-Alder intermolecular reaction between 2,4,6-tris(2-furanyl methyl imino)-1,3,5-triazine and various bis(maleimide) compounds without evolution of by-products. The resulting composites were characterized by mechanical properties.

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 Containing an s-Triazine Ring

2000 ◽  
Vol 12 (1) ◽  
pp. 225-235 ◽  
Author(s):  
H S Patel ◽  
V C Patel
Keyword(s):  
Diels Alder ◽  
Spectral Studies ◽  
Reinforced Composites ◽  
Intermolecular Reaction ◽  
Glass Fibre Reinforced ◽  
Glass Fibre Reinforced Composites ◽  
By Products ◽  
Fibre Reinforced Composites ◽  
Chemical Resistivity

A series of new polyimides containing an s-triazine nucleus were prepared via Diels–Alder (DA) intermolecular polymerization of 2,6-bis(2-furanyl methyl imino)-4-ethoxy-1,3,5-triazine with different bis(maleimide) compounds. The DA reaction was carried out in tetrahydrofuran as solvent, as well as in bulk followed by aromatization of poly(tetrahydrophthalimido)-intermediates in the presence of acetic anhydride. All the poly(imino- s-triazine imide)s were characterized by elemental analysis, IR spectral studies and thermogravimetry. Glass fibre reinforced composites were prepared via in situ Diels–Alder intermolecular reaction between 2,6-bis(2-furanyl methyl imino)-4-ethoxy-1,3,5-triazine and different bis(maleimide) compounds without evolution of by-products. The prepared composites were characterized by chemical resistivity and mechanical properties.

Effect of Heat Treatment on the Properties of Polyetheretherketone and its Composite

2021 ◽  
Vol 1167 ◽  
pp. 23-33
Author(s):  
Alaa A. Mohammed
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Thermal Stability ◽  
Bioactive Glass ◽  
Glass Powder ◽  
Chemical Resistance ◽  
Positive Influence ◽  
Thermoplastic Polymer ◽  
High Chemical ◽  
High Chemical Resistance

Polyetheretherketone (PEEK) is a semicrystalline thermoplastic polymer with high chemical resistance, thermal stability and excellent mechanical properties. In the present work, neat PEEK and 3% bioactive glass/PEEK composites were annealed at various temperatures (100 °C, 200 °C and 300 °C) for (30 and 60) min and characterized with mechanical and density tests, differential scanning calorimetery and Fourier transform infrared spectroscopy. Results manifested bioactive glass powder enhanced the properties of the PEEK matrix. Thermal annealing at (200 and 300 °C) had a positive influence on the mechanical properties and density owing to increase in the level of crystallinity, whereas annealing at (100 °C) had not effect on the properties.

In situ polymerization approach to functionalized MoS2/polyethylene nanocomposites with enhanced thermal stability and mechanical properties

RSC Advances ◽  
2016 ◽  
Vol 6 (113) ◽  
pp. 112429-112434 ◽  
Author(s):  
Hao Zhang ◽  
Young-Kwon Moon ◽  
Xue-Quan Zhang ◽  
He-Xin Zhang ◽  
Keun-Byoung Yoon
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Transition Metal ◽  
In Situ Polymerization ◽  
Transition Metal Dichalcogenide

The in situ polymerization approach proposed here will open a new and exciting avenue for the development of transition metal dichalcogenide reinforced polyethylene nanocomposites.

scholarly journals Novel tanning agent based on silica-nanocomposite emulsion polymers

2020 ◽  
Vol 49 (4) ◽  
pp. 283-294
Author(s):  
Abd El-Wahab H. ◽  
Farouk Abd El-Monem ◽  
Naser M.A. ◽  
Hussain A.I. ◽  
El-Shahat H.A. Nashy ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Butyl Acrylate ◽  
Solid Content ◽  
Nano Silica ◽  
Drying Time ◽  
Content Type ◽  
Chrome Tanning ◽  
Emulsion Polymers

Purpose The purpose of this paper is devoted to application of the emulsion polymer of poly(methyl methacrylate-co-butyl acrylate) prepared with in situ nano-silica as a novel tanning agent of hide to partly or totally replace chrome salt and to improve physical, thermal and mechanical properties of the tanned leather and to reduce the environmental impact of chrome tanning effluent. Design/methodology/approach Polymer/nano-silica hybrid emulsions were prepared via in situ seed emulsion polymerisation. The prepared polymers were characterised for solid content, molecular weight, viscosity, drying time, minimum film-forming temperature (MFFT) and microstructures (via transmission electron microscopy). The mechanical, thermal and surface morphological (by scanning electron microscope) properties of the treated samples were also investigated. The influences of the increase in the content of organic nano-silica on the properties of the tanned leather are discussed. Findings It was found that the viscosity, the particle size and the solid content of the prepared polymers increased as the content of the nano-silica increased while gloss and drying time of the resulting polymer film decreased. Tanning buffalo hide by Polymer F (containing a high content of nano-silica) gave desirable properties in terms of tensile strength, thermal stability and shrinkage temperature. Research limitations/implications This paper discusses the preparation and the characterisation of emulsion polymers with in situ nano-silica and their application in tanning process to enhance and improve the leather quality, as well as reduce the use of chrome tanning materials and consequently chrome tanning waste. Practical implications The tanned leather showed an improvement of physico-mechanical properties and enhancement of thermal stability. Furthermore, the tanned leather has uniform colour, softness and firmness of grain. All these promising results provide evidence to support the applicability of the prepared co-polymer/nano-silica emulsions as an efficient tanning agent that also provides lubricating properties for leather. Originality/value Since May 2015, REACH Annex XVII restricts Cr(VI) in leather articles or leather parts of articles that come into contact with skin to a concentration of less than 3 mg/kg. Cases of discovery of Cr(VI) in leather papers have been reported by the European rapid alert system on dangerous consumer products (RAPEX). The emulsion poly (methyl methacrylate-co-butyl acrylate) with in situ nano-silica that has been developed via the study reported in this paper is one of the better technologies for the reduction of chromium ratio used in tanning industry.

scholarly journals Combined Chemical Modification of Bamboo Material Prepared Using Vinyl Acetate and Methyl Methacrylate: Dimensional Stability, Chemical Structure, and Dynamic Mechanical Properties

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1651 ◽  
Author(s):  
Saisai Huang ◽  
Qiufang Jiang ◽  
Bin Yu ◽  
Yujing Nie ◽  
Zhongqing Ma ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Chemical Modification ◽  
Methyl Methacrylate ◽  
Vinyl Acetate ◽  
Dimensional Stability ◽  
Chemical Structure ◽  
In Situ Polymerization ◽  
Dynamic Mechanical Properties

Acetylation and in situ polymerization are two typical chemical modifications that are used to improve the dimensional stability of bamboo. In this work, the combination of chemical modification of vinyl acetate (VA) acetylation and methyl methacrylate (MMA) in situ polymerization of bamboo was employed. Performances of the treated bamboo were evaluated in terms of dimensional stability, wettability, thermal stability, chemical structure, and dynamic mechanical properties. Results show that the performances (dimensional stability, thermal stability, and wettability) of bamboo that was prepared via the combined pretreatment of VA and MMA (VA/MMA-B) were better than those of raw bamboo, VA single-treated bamboo (VA-B), and MMA single-treated bamboo (MMA-B). According to scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analyses, VA and MMA were mainly grafted onto the surface of the cell wall or in the bamboo cell lumen. The antiswelling efficiency and contact angle of VA/MMA-B increased to maximum values of 40.71% and 107.1°, respectively. From thermogravimetric analysis (TG/DTG curves), the highest onset decomposition temperature (277 °C) was observed in VA/MMA-B. From DMA analysis, the storage modulus (E’) of VA/MMA-B increased sharply from 15,057 Pa (untreated bamboo) to 17,909 Pa (single-treated bamboo), and the glass transition temperature was improved from 180 °C (raw bamboo) to 205 °C (single-treated bamboo).

Polyimide foams with outstanding flame resistance and mechanical properties by the incorporation of noncovalent bond modified graphene oxide

2020 ◽  
Vol 44 (28) ◽  
pp. 12068-12078 ◽  
Author(s):  
Hongtao Liu ◽  
Huafeng Tian ◽  
Yuanyuan Yao ◽  
Aiming Xiang ◽  
Haisong Qi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Graphene Oxide ◽  
Flame Resistance ◽  
Noncovalent Bond ◽  
Composite Foams ◽  
Modified Graphene Oxide ◽  
Modified Graphene

PI composite foams were in situ generated by incorporating modified GO to further improve flame resistance, thermal stability and mechanical properties.

Synthesis and Properties of Melamine-Formaldehyde/Montmorillonite Nanocomposites

2008 ◽  
Vol 8 (4) ◽  
pp. 1775-1781 ◽  
Author(s):  
Haitao Wang ◽  
Xiangfu Meng ◽  
Zhongzhong Qian ◽  
Hu Zhou ◽  
Yanfen Ding ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Raman Spectroscopy ◽  
Chemical Resistance ◽  
Formaldehyde Resin ◽  
Polycondensation Reaction ◽  
Melamine Formaldehyde ◽  
Formaldehyde Content ◽  
Acetyl Acetone ◽  
Modified Montmorillonite

In this paper, intercalated and partially exfoliated melamine-formaldehyde (MF)/montmorillonite (MMT) nanocomposites have been synthesized successfully via in-situ polymerization based on pristine montmorillonite, acidified montmorillonite and organic modified montmorillonite respectively. The obtained nanocomposites were characterized by XRD, TEM, TGA, and Raman spectroscopy. Free formaldehyde content of those composites was also determined by acetyl acetone technique. It was found that acidified montmorillonite and organic modified montmorillonite could catalyze the polycondensation reaction of methylolmelamines. The thermal stability and chemical resistance of those two nanocomposites were also improved dramatically compared to pure melamine-formaldehyde resin.

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