A5102938188- Flame retardant materials and properties
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Synthesis and properties of polymers
- Epoxy Resin Curing Processes
- Organophosphorus compounds synthesis
- Fire dynamics and safety research
- Crystallography and molecular interactions
- Synthesis and Reactivity of Sulfur-Containing Compounds
- Synthesis and Biological Evaluation
- Synthesis of Organic Compounds
- Synthesis and Characterization of Heterocyclic Compounds
- Synthesis and Reactivity of Heterocycles
- Catalytic C–H Functionalization Methods
- Organometallic Complex Synthesis and Catalysis
- Chemical Reaction Mechanisms
- Synthesis and characterization of novel inorganic/organometallic compounds
- Phosphorus compounds and reactions
- Photopolymerization techniques and applications
- Chemical Synthesis and Reactions
- Carbon dioxide utilization in catalysis
- Silicone and Siloxane Chemistry
- Quinazolinone synthesis and applications
- Lanthanide and Transition Metal Complexes
- VLSI and FPGA Design Techniques
Fraunhofer Institute for Structural Durability and System Reliability
2012-2023
Fraunhofer Society
2014
Karlsruhe Institute of Technology
2002-2012
Adolphe Merkle Institute
2012
University of Fribourg
2012
FZI Research Center for Information Technology
2002-2011
FIZ Karlsruhe – Leibniz Institute for Information Infrastructure
2008-2009
University of Rochester
1982
Condensed-phase mechanisms play a major role in fire-retardant polymers. Generations of development have followed the concept charring to improve fire properties. Whereas principal reactions are believed be known, specific description for multicomponent systems is lacking, as picture across different systems. A two-step approach proposed general, and also presented greater detail. The second step covers controlling charring, whereas actual reactants provided preceding step. This model...
Abstract The pyrolysis of an epoxy resin and the fire behavior corresponding carbon fiber‐reinforced composites, both flame‐retarded with either 10‐ethyl‐9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene 10‐oxide or 1,3,5‐tris[2‐(9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene 10‐oxide‐10‐)ethyl]1, 3,5‐triazine‐2,4,6(1H,3H,5H)‐trione, are investigated. different retardancy mechanisms discussed, their influence on properties assessed, in particular for flammability (limiting oxygen index, UL 94) developing...
Abstract The pyrolysis and fire behavior of halogen‐free flame‐retarded DGEBA/DMC, RTM6 their corresponding 60 vol.‐% carbon fibers (CF) composites were investigated. A novel phosphorous compound (DOPI) was used. Its action is dependent on the epoxy matrix. DGEBA/DMC DOPI decompose independently each other. Only flame inhibition occurs in gas phase. shows a condensed phase interaction increasing charring. Both mechanisms decrease with irradiance, whereas RTM6‐CF charring suppressed at low...
Abstract 10‐Ethyl‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide ( 1 ) can be nitrated using acetic anhydride and fuming nitric acid. The nitro group is reduced palladium on charcoal hydrogen. These reaction conditions are used for the synthesis of an analogous DOPO‐based diaminic hardener 7 ). An evaluation curing behavior, mechanical properties flammability a neat resin made DGEBA (DGEBA + carbon fiber‐reinforced DGEBA, 4,4′‐diaminodiphenylsulfon (DDS) DDS shows potential this to lead...
This report presents the synthesis and use of novel derivatives 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO, 1 ) 5,5‐dimethyl‐1,3,2‐dioxaphosphorinan‐2‐one (DDPO, 2 as flame retardant additives for epoxy resins. DOPO‐based DDPO‐based compounds were synthesized via nucleophilic substitution with 1,3,5‐tris‐(2‐hydroxyethyl) isocyanurate (THIC, 3 subsequent oxidation (Schemes 2). Another trivalent DOPO derivative recently reported by our group was obtained transamination followed a...
Abstract Novel derivatives of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) were obtained by a simple synthetic route and incorporated in epoxy resins, consisting novolac (DEN 438), dicyandiamide (DICY), fenuron. The thermal fire‐retardant properties DICY‐cured DEN 438 samples containing the novel DOPO‐based additives investigated differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), UL 94 test. results compared to those specimens commercially available...
After complexation with copper(II) ions, Schiff bases 1a−d may undergo an oxidative ring closure using atmospheric oxygen to give a number of imidazo[1,5-a]pyridines 2, imidazo[1,5-a]imidazole 3, and imidazo[5,1-a]isochinoline 4. This ligand oxidation can be performed catalytic amounts copper ions in the reaction. A cycle for copper-catalyzed heterocyclization will presented together isolated complexes 1a,b intermediates 5 8 that were found by X-ray structure analyses which confirm this...
Abstract Summary: The decomposition of novel phosphorus‐containing poly(oxyphenylene‐sulfonyl‐phenylene‐oxy‐diphenyl phenylene phosphine oxide) (PSU_I), 2,5‐dihydroxy‐1‐biphenylene‐phosphine oxide based polysulfone (PSU_II), poly(sulfonyl‐diphenylphenylene phosphonate) (PSU_P) and bisphenol A‐based (PSU) is studied. influence the chemical structure, charring phosphorus release discussed on mass loss, kinetics products. pyrolysis fire behaviour blends with epoxy resin (EP) are For EP‐PSU_II,...
Starting from Schiff bases 1, a wide variety of heterobicycles, which can be applied as pharmaceuticals or ligands for catalysts, is accessible by copper-catalyzed oxidation with atmospheric oxygen. The scheme shows, example, the synthesis imidazo[1,5-a]pyridines 2 (R1=2-hydroxy-3-methoxyphenyl, tBu, 2-hydroxyphenyl, 2-aminophenyl; R2=2-pyridyl, Me, phenyl). Supporting information this article available on WWW under http://www.wiley-vch.de/contents/jc_2002/2002/z18417_s.pdf author. Please...
DOPO and its derivatives generally exhibit an outstanding performance as flame retardants in various polymers. Starting from trivalent 10-alkoxy-10H-9-oxa-10-phosphaphenanthrenes, a broad range of was synthesized via transesterification with aliphatic alcohols subsequent Michaelis-Arbuzov rearrangement using catalytic amounts p-toluenesulfonic acid methylester. Due to the considerable differences nature employed, several procedures for processing them are presented.
Abstract Summary: The synthesis of novel phosphorous‐containing aromatic polyethers P‐PEEK and P‐PSU, based on poly(ether ether ketone)s (PEEK) sulfone)s (PSU) was carried out successfully by using diols instead bisphenol A in the usual procedure. molecular weights P‐PEEKs P‐PSUs obtained reflect both influence different halogen components used lower thermal stabilities compared to A. However, polymers with sufficient could be obtained, having interestingly high T g s, as well modified flame...
Abstract A comparative evaluation of systematically tailored chemical structures various phosphorus‐containing aminic hardeners for epoxy resins was carried out. In particular, the effect oxidation state phosphorus in hardener molecule on curing behavior, mechanical, thermomechanical, and hot‐wet properties a cured bifunctional bisphenol‐A based thermoset is discussed. Particular attention paid to pyrolysis neat containing phosphine oxide, phosphinate, phosphonate, phosphate (with content...
Abstract 9,10-Dihydro-9,10-oxa-10-phosphaphenanthrene-10-oxide (DOPO) has been commercialized as a gas phase active flame retardant. Its P‒H bond allows its reactive incorporation into epoxy resins and formation of new additives via Michael-like addition. To better understand the role radicals in retardant mechanism, 9,10-dihydro-9-aza-10-phosphaphenanthrene-10-oxide (DAPO) 9,10-dihydro-9,10-oxa-10-phosphaphenanthrene-10-sulfide (DOPS) were synthesized. DAPO was found to undergo...