Study on Synthesis of Cyclotriphosphazene Containing Aminopropylsilicone Functional Group as Flame Retardant

2013 ◽  
Vol 683 ◽  
pp. 25-29 ◽  
Author(s):  
Lan Lan He ◽  
Yi Zhang ◽  
Zhao Lu Qin ◽  
Yan Hua Lan ◽  
Ding Hua Li ◽  
...  

A novel non-halogen flame retardant APESP, cyclotriphosphazene containing six aminopropyltriethoxysilicone functional groups N3P3[NH(CH2)3Si(OCH2CH3)3]6, was synthesized by menas of SN2 nucleophilic substitution reaction, using hexachlorocyclotriphosphazene(HCCP) and 3-aminopropyltriethoxy-silane (KH550) as material. Firstly the industrial grade HCCP was purified through recrystallization and sublimation. Then the reaction process was investigated to prompt the yield, and the optimum reaction conditions were as follows: triethylamine as acid-binding agent, tetrahydrofuran as solvent, HCCP/KH550/triethylamine molar ratio 1:7.2:7.2, dripping time: 1 hour, temperature: 67°C and reaction time: 20h. Maximum APESP yield reached 94.3%. The chemical structure and purity was characterized by element analysis, Fourier-transformed infrared spectroscopy (FTIR), mass spectrum, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) analysis. The results showed that the structure of synthesized product is consistent with the theoretical structure, in which the chlorine atoms were completely substituted. The charge distribution calculation of HCCP and KH550 confirmed the reaction mechanism.

2011 ◽  
Vol 396-398 ◽  
pp. 2411-2415 ◽  
Author(s):  
Ping Lan ◽  
Li Hong Lan ◽  
Tao Xie ◽  
An Ping Liao

Isoamyl acetate was synthesized from isoamylol and glacial acetic acid with strong acidic cation exchanger as catalyst. The effects of reaction conditions such as acid-alcohol ratio, reaction time, catalyst dosage to esterification reaction have been investigated and the optimum reaction conditions can be concluded as: the molar ratio of acetic acid to isoamylol 0.8:1, reaction time 2h, 25 % of catalyst (quality of acetic acid as benchmark). The conversion rate can reach up to 75.46%. The catalytic ability didn’t reduce significantly after reusing 10 times and the results showed that the catalyst exhibited preferably catalytic activity and reusability.


2012 ◽  
Vol 506 ◽  
pp. 158-161 ◽  
Author(s):  
A. Jaidee ◽  
Pornchai Rachtanapun ◽  
S. Luangkamin

N,O-Carboxymethyl chitosans were synthesized by the reaction between shrimp, crab and squid chitosans with monochloroacetic acid under basic conditions at 50°C. The mole ratio of reactants was obtained from various reaction conditions of shrimp chitosan polymer and oligomer types. The mole ratio 1:12:6 of chitosan:sodium hydroxide:monochloroacetic acid was used for preparing carboxymethyl of chitosan polymer types while carboxymethyl of chitosan oligomer types were used the mole ratio 1:6:3 of chitosan:sodium hydroxide:monochloroacetic acid. The chemical structure was analyzed by fourier transformed infrared spectroscopy (FT-IR) and proton nuclear magnatic resonance spectroscopy (1H-NMR). The FT-IR was used for confirm the insertion of carboxymethyl group on chitosan molecules. The 1H-NMR was used for determining the degree of substitution (DS) of carboxymethylation at hydroxyl and amino sites of chitosans. Carboxymethyl chitosan samples had the total DS of carboxymethylation ranging from 1.0-2.2. The highest of DS of carboxymethylation was from shrimp chitosan oligomer type.


Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1357
Author(s):  
Ronaldo Rodrigues de Sousa ◽  
Ayla Sant’Ana da Silva ◽  
Roberto Fernandez-Lafuente ◽  
Viridiana Santana Ferreira-Leitão

The adoption of biocatalysis in solvent-free systems is an alternative to establish a greener esters production. An interesting correlation between the acid:alcohol molar ratio and biocatalyst (immobilized lipase) loading in the optimization of ester syntheses in solvent-free systems had been observed and explored. A simple mathematical tool named Substrate-Enzyme Relation (SER) has been developed, indicating a range of reaction conditions that resulted in high conversions. Here, SER utility has been validated using data from the literature and experimental assays, totalizing 39 different examples of solvent-free enzymatic esterifications. We found a good correlation between the SER trends and reaction conditions that promoted high conversions on the syntheses of short, mid, or long-chain esters. Moreover, the predictions obtained with SER are coherent with thermodynamic and kinetics aspects of enzymatic esterification in solvent-free systems. SER is an easy-to-handle tool to predict the reaction behavior, allowing obtaining optimum reaction conditions with a reduced number of experiments, including the adoption of reduced biocatalysts loadings.


2010 ◽  
Vol 88 (10) ◽  
pp. 1046-1052 ◽  
Author(s):  
Aman Khan ◽  
Robert A. Gossage ◽  
Daniel A. Foucher

The quantitative conversion of the tertiary stannane (n-Bu)3SnH (2) into (n-Bu)6Sn2 (4) was achieved by heating the neat hydride material under low pressure or under closed inert atmosphere conditions. A 31% conversion of Ph3SnH (3) to Ph6Sn2 (5) was also observed under low pressure; however, under closed inert atmosphere conditions afforded Ph4Sn (6) as the major product. A mixed distannane, (n-Bu)3SnSnPh3 (7), can also be prepared in good yield utilizing an equal molar ratio of 2 and 3 and the same reaction conditions used to prepare 4. This solvent-free, catalyst-free route to distannanes was extended to a secondary stannane, (n-Bu)2SnH2 (8), which yielded evidence (NMR) for hydride terminated distannane H(n-Bu)2SnSn(n-Bu)2H (9), the polystannane [(n-Bu)2Sn]n (10), and various cyclic stannanes [(n-Bu)2Sn]n=5,6 (11, 12). Further evidence for 10 was afforded by gel permeation chromatography (GPC) where a broad, moderate molecular weight, but highly dispersed polymer, was obtained (Mw = 1.8 × 104 Da, polydispersity index (PDI) = 6.9) and a characteristic UV–vis absorbance (λmax) of ≈370 nm observed.


2014 ◽  
Vol 1033-1034 ◽  
pp. 7-11
Author(s):  
Yan Bai ◽  
Xuan Tang ◽  
Kui Zhou ◽  
Cun She Zhang

bis(2-chloroethoxy)methane was synthesized by the reaction of ethylene chlorohydrin and Oligopolyformaldehyde under sulfuric acid catalysis. optimum reaction conditions obtained were as follows: the molar ratio of Oligopolyformaldehyde and ethylene chlorohydrin of 1.2:2, catalyst dosage was 5‰mass fraction of ethylene chlorohydrin, toluene were chose as water-carrying agent, All reactant were refluxed on temperature of 110°C until no water generated. Under the optimum conditions the yield of bis(2-chloroethoxy)methane was 97.7%. The structure of bis(2-chloroethoxy)methane were conformed by ATR IR. The purity of bis(2-chloroethoxy)methane were 99% by gas chromatographic detection.


2013 ◽  
Vol 781-784 ◽  
pp. 190-193
Author(s):  
Mei Xu ◽  
Hua Yuan ◽  
Wei Liu ◽  
Jian Wang ◽  
Feng Zhen Yang

The synthesis of isoamyl acetate with ammonium 9-molybdate manganese heteropolyacid salt supported activated carbon as catalyst was studied. The optimum reaction conditions are obtained as follows: isoamyl alcohol to acetic acid molar ratio = 1.646, the weight of catalyst is 40% of total weigh, m (acidulate catalyst)=0.2g, m (water carrying reagent toluene) = 3ml, reaction time is about 63 minutes. Selectivity is 100% and conversion rate is 89.48%.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Subrata Das ◽  
Ashim Jyoti Thakur ◽  
Dhanapati Deka

Biodiesel was produced from high free fatty acid (FFA)Jatropha curcasoil (JCO) by two-stage process in which esterification was performed by Brønsted acidic ionic liquid 1-(1-butylsulfonic)-3-methylimidazolium chloride ([BSMIM]Cl) followed by KOH catalyzed transesterification. Maximum FFA conversion of 93.9% was achieved and it reduced from 8.15 wt% to 0.49 wt% under the optimum reaction conditions of methanol oil molar ratio 12 : 1 and 10 wt% of ionic liquid catalyst at 70°C in 6 h. The ionic liquid catalyst was reusable up to four times of consecutive runs under the optimum reaction conditions. At the second stage, the esterified JCO was transesterified by using 1.3 wt% KOH and methanol oil molar ratio of 6 : 1 in 20 min at 64°C. The yield of the final biodiesel was found to be 98.6% as analyzed by NMR spectroscopy. Chemical composition of the final biodiesel was also determined by GC-MS analysis.


Author(s):  
Ganapati D. Yadav ◽  
Jyoti B. Sontakke

Optically active 1-phenylethanol is used as a chiral building block and synthetic intermediate in pharmaceutical and fine-chemical industries. Lipase - catalyzed kinetic resolution of (R,S)-1-phenylethanol with vinyl acetate as an acyl donor and Candida antarctica immobilized lipase as a biocatalyst in a batch reactor was optimized using Response Surface Methodology (RSM). Four-factor-five-level central composite rotatable design (CCRD) was employed to evaluate the effect of synthesis parameters such as speed of agitation, enzyme loading, temperature and acyl donor/alcohol molar ratio, on conversion, enantiomeric excess (ee), enantioselectivity and initial rate. Optimum reaction conditions obtained were; mole ratio of acyl donor: ester of 2:1, temperature of 42.5 °C, catalyst loading of 1.6x10-3 g.cm-3 and speed of agitation of 336 rpm. Analysis of variance was performed to determine significantly affecting variables and interactions between the process parameters.


2015 ◽  
Vol 21 (1-1) ◽  
pp. 113-121 ◽  
Author(s):  
Laishun Shi ◽  
Meijie Sun ◽  
Na Li ◽  
Bochen Zhang

A novel betaine type asphalt emulsifier 3-(N,N,N-dimethyl acetoxy ammonium chloride)-2-hydroxypropyl laurate was synthesized after three steps by the reaction of lauric acid, epichlorohydrin, dimethylamine and sodium chloroacetate. The optimum reaction conditions were obtained for the synthesis of the first step of 3-chloro-2-hydroxypropyl laurate. The esterification yield reaches 97.1% at the optimum conditions of reaction temperature 80?C, reaction time 6 h, feedstock mole ratio of epichlorohydrin to lauric acid 1.5, mass ratio of catalyst to lauric acid 2%. The chemical structure of the product was characterized by FTIR and 1H NMR. The first synthesis step of 3-chloro-2-hydroxypropyl laurate was monitored by online FTIR technique. The by-product was detected by the online FTIR analysis. Based upon the experimental data, a plausible reaction mechanism was proposed for the reaction. The CMC of the objective product has a lower value of 7.4?10-4 mol/L. The surface tension at CMC is 30.85 mN/m. The emulsifier is a rapid-set asphalt emulsifier.


2003 ◽  
Vol 11 (1) ◽  
pp. 19-29 ◽  
Author(s):  
Ghanshyam S. Chauhan ◽  
Lalit Guleria ◽  
Harinder Lal

Cellulose extracted from pine needles was graft copolymerized with acrylamide using benzoyl peroxide as initiator. Following a novel synthetic strategy and using the optimum reaction conditions evaluated for the grafting of acrylamide, some comonomers viz: glycidyl methacrylate, 2-hydroxyethyl methacrylate, acrylic acid and acrylonitrile have been grafted along with acrylamide using five different concentrations of the comonomers. SEM, FT-IR and thermal studies of graft copolymers were carried to obtain evidence of the incorporation of acrylamide and comonomers into cellulose. Reactivity of acrylamide in grafting reactions alone and in the presence of comonomers has been studied. The molar ratio of acrylamide and comonomers, and hence the structure of the graft chain remains independent of the comonomer concentration in the feed. It has also been observed that compared to acrylamide, less acrylonitrile was incorporated while far higher amount of the methacrylates were incorporated in the graft chain.


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