A high-performance polycyanurate network derived from 4,4′-biscyanato-2,2′-trifluoromethylbiphenyl

2020 ◽  
Vol 11 (4) ◽  
pp. 784-788
Author(s):  
Jingfeng Liu ◽  
Qingjie Meng ◽  
Liying Li ◽  
Gewu Lu ◽  
Hang Yuan ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Bisphenol A ◽  
High Performance

Polycyanurates with excellent thermal, mechanical, and dielectric properties were derived from 4,4′-biscyanato-2,2′-trifluoromethylbiphenyl, and their properties were systematically compared with those of polycyanurates derived from bisphenol A dicyanate.

scholarly journals Micromorphology and Mechanical and Dielectric Properties of Bismaleimide Composite Modified by Multiwalled Carbon Nanotubes and Polyethersulfone

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Yufei Chen ◽  
Chengbao Geng ◽  
Yang Han ◽  
Mingzhuo Chai ◽  
Hongyuan Guo ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electron Microscope ◽  
Dielectric Properties ◽  
Bisphenol A ◽  
Multiwalled Carbon Nanotubes ◽  
High Performance ◽  
Sol Gel ◽  
Alder Reaction ◽  
Multiwalled Carbon ◽  
The Impact

Multiwalled carbon nanotubes (MWCNTs) were modified by oxidizing agent to obtain O-MWCNTs, and the surface of it was coated with active group. 4,4′-Diaminodiphenylmethane bismaleimide (MBMI) was used as matrix, 3,3′-diallyl bisphenol A (BBA) and bisphenol-A diallyl ether (BBE) were used as reactive diluent, polyethersulfone (PES) as toughening agent, and O-MWCNTs as modifier; OMWCNT/PES-MBAE composite was prepared through in situ sol-gel method. The effect of PES and OMWCNTs on the mechanical and dielectric properties of composite was analyzed, and the microstructure was examined by transmission electron microscope (TEM) and scanning electron microscope (SEM). The mechanism of composite toughened by PES and OMWCNTs was observed and analyzed. The results showed that Diels-Alder reaction between MBMI and allyl compounds occurred completely and unsaturated double bond disappeared. O-MWCNTs and PES resin dispersed smoothly in polymer matrix and were used as reinforcement, and PES resin and O-MWCNTs could synergistically improve the properties of the composite and exhibited a typical ductile fracture. The impact and bending strengths were 16.09 kJ/m2 and 153.57 MPa, which were 74.32% and 53.08% higher than those of the MBAE matrix, respectively, and the dielectric constant and the dielectric loss were 3.76 (100 Hz) and 2.79 × 10−3 (100 Hz), when the content of PES was 2 wt% and O-MWCNTs was 0.02 wt%. The outstanding properties of the material made it play an important role in high-performance insulating material applications.

Determination of Bisphenol A in Milk and Dairy Products by High-Performance Liquid Chromatography with Fluorescence Detection

2003 ◽  
Vol 66 (8) ◽  
pp. 1439-1443 ◽  
Author(s):  
JEONG-HUN KANG ◽  
FUSAO KONDO
Keyword(s):  
Bisphenol A ◽  
Dairy Products ◽  
High Performance ◽  
Solid Phase ◽  
Skim Milk ◽  
The European Union ◽  
Condensed Milk ◽  
Oasis Hlb ◽  
Milk And Dairy Products

This study was conducted to develop a selective and sensitive method for the determination of bisphenol A (BPA) levels in milk and dairy products. A method based on solvent extraction with acetonitrile and solid-phase extraction (SPE) was developed for the analysis of BPA in milk, yogurt, cream, butter, pudding, condensed milk, and flavored milk, and a method using two SPE cartridges (OASIS HLB and Florisil cartridge) for skim milk was also developed. The developed methods showed good recovery levels (77 to 102%) together with low detection limits (1 μg/liter for milk, yogurt, pudding, condensed milk, flavored milk, and skim milk and 3 μg/liter for cream and butter). These methods are simple, sensitive, and suitable for the analysis of BPA in milk and dairy products. When 40 milk and dairy products were analyzed by the proposed methods, BPA was not identified in noncanned products, but its levels ranged from 21 to 43 μg/kg in canned products, levels that were 60- to 140-fold lower than the migration limits in the European Union and Japan.

Research on In Situ Anionic Polymerization of PA6/PI Alloy

2011 ◽  
Vol 295-297 ◽  
pp. 21-25
Author(s):  
Hong Kai Zhao ◽  
Li Guang Xiao ◽  
Hong Jie Wang
Keyword(s):  
Molecular Weight ◽  
Bisphenol A ◽  
High Performance ◽  
Hot Spot ◽  
Microscopic Analysis ◽  
Infrared Analysis ◽  
Elongation At Break ◽  
System Temperature ◽  
Lamellar Crystals

High performance trend of plastics has become a hot spot of current research. Select bisphenol A dianhydride and bisphenol A diamine with excellent water resistance as the reactant monomers to obtain anhydride-terminated polyimide with very high molecular weight by two-step polymerization, graft the active radicals of acyl caprolactam using the activity of anhydride and obtain PI modified nylon resin by polymerization.When the system temperature is above 160 °C and the added modifiers are greater than 10%, the system viscosity increases very fast; when the system temperature reaches 140 °C and the added modifiers are at 5%, the system viscosity increases very slowly. It is proved that the reaction in each above step is successful through infrared analysis. The mechanical properties of modified PI nylon increases with the increase of consumption and molecular weight of polyimide, when the molecular weight is selected to be about 8000~10000 and the adding amount is 10wt%~15 wt%, the tensile strength reaches over 85MPa, the notch impact strength is increased to 19.6kJ.m-2 and the elongation at break reaches 18%, which are remarkably better than general engineering plastics.Through microscopic analysis, the molecules of polyimide does not enter crystallization phase of nylon resin, but forms compact lamellar crystals existing in nylon matrix.

scholarly journals Microstructure and Properties of SCE-Al2O3/PES-MBAE Composite

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Yufei Chen ◽  
Qiwang Dai ◽  
Xiwang Zhang ◽  
Tao Feng
Keyword(s):  
Dielectric Properties ◽  
Bisphenol A ◽  
Heat Resistance ◽  
Bending Strength ◽  
Sol Gel ◽  
Harmful Effect ◽  
Decomposition Temperature ◽  
Two Phase ◽  
Allyl Compound

SCE-Al2O3was the nano-Al2O3modified by supercritical ethanol and the surface of SCE-Al2O3was coated with active group. 4,4′-diaminodiphenylmethane bismaleimide (MBMI) was used as matrix; 3,3′-diallyl bisphenol A (BBA) and bisphenol-A diallyl ether (BBE) were used as reactive diluent, polyethersulfone (PES) as toughening agent, and SCE-Al2O3as modifier; SCE-Al2O3/PES-MBAE nanocomposite was prepared through in situ sol-gel method. The mechanism of composite toughened by PES was observed and analyzed. FTIR indicated that the reaction between MBMI and allyl compound occurred and SCE-Al2O3had doped into the polymer matrix. SEM showed that PES particle was inlaid in matrix and presented as a two-phase structure in matrix. The heat resistance, dielectric properties, and mechanical properties of SCE-Al2O3/PES-MBAE nanocomposites were evaluated. The results showed that with the incorporation of PES, although the toughness of the material improved, the heat resistance and dielectric properties of material declined, meanwhile. The adulteration of SCE-Al2O3could remedy the harmful effect caused by PES, while the content of SCE-Al2O3was reasonable. The decomposition temperature, dielectric constant, and dielectric loss of composite were 441.23°C, 3.63 (100 Hz), and 1.52 × 10−3(100 Hz); the bending strength and impact strength were 129.22 MPa and 13.19 kJ/mm2, respectively, when the content of SCE-Al2O3was 3 wt% and PES was 5 wt%.

Higher Serum Bisphenol A Levels in Diabetic Hemodialysis Patients

2016 ◽  
Vol 42 (1) ◽  
pp. 77-82 ◽  
Author(s):  
Faruk Turgut ◽  
Sana Sungur ◽  
Ramazan Okur ◽  
Mustafa Yaprak ◽  
Muge Ozsan ◽  
...  
Keyword(s):  
Bisphenol A ◽  
High Performance ◽  
Patient Characteristics ◽  
Hemodialysis Patients ◽  
Chronic Hemodialysis ◽  
Dialysis Session ◽  
Laboratory Parameters ◽  
Hemodialysis Session ◽  
Before And After ◽  
Patients With Diabetes

Background: Bisphenol A (BPA) has been implicated as an ‘endocrine disruptor'. We aimed at exploring the association between serum BPA levels and patient characteristics, particularly the presence of diabetes mellitus, and laboratory parameters in hemodialysis patients. Methods: This study included 47 chronic hemodialysis patients. Patient characteristics were recorded. Blood was drawn before and after hemodialysis session. Serum BPA levels were measured by the high-performance-liquid-chromatography and laboratory parameters were measured by using standard methods. Results: In hemodialysis patients, postdialysis serum BPA levels were significantly higher than predialysis after a single hemodialysis session (5.57 ± 1.2 vs. 4.06 ± 0.73, p < 0.0001). Predialysis serum BPA levels were significantly higher in patients with diabetes than non-diabetics (4.4 ± 0.6 vs. 3.9 ± 0.7, p = 0.025). No association was found between serum BPA levels and patient characteristics, and particularly laboratory parameters. Conclusion: Serum BPA levels were rising significantly after a single dialysis session. Diabetic hemodialysis patients had higher predialysis serum BPA levels.

BPA-Free High-Performance Sustainable Polycarbonates Derived from Non-Estrogenic Bio-Based Phenols

2021 ◽  
Author(s):  
Michael Garrison ◽  
Perrin Storch ◽  
William S. Eck ◽  
Valerie Adams ◽  
Patrick Fedick ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Epoxy Resins ◽  
High Performance ◽  
High Volume ◽  
Endocrine Disrupter

Bisphenol A (BPA) is a versatile petrochemical used in the preparation of high volume polymers including polycarbonates and epoxy resins. Unfortunately, BPA is also an endocrine disrupter and has been...

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