Synthesis and Characterization of Block Copolymer from Natural Rubber, Toluene-2,4-Diisocyanate and Poly(ξ-aprolactone) Diol-Based Polyurethane

2011 ◽  
Vol 695 ◽  
pp. 316-319 ◽  
Author(s):  
Wannarat Panwiriyarat ◽  
Varaporn Tanrattanakul ◽  
Jean François Pilard ◽  
Chuanpit Khaokong
Keyword(s):  
Block Copolymer ◽  
Natural Rubber ◽  
Soft Segment ◽  
Molar Ratio ◽  
H Nmr ◽  
Chain Cleavage ◽  
Epoxidation Reaction ◽  
Liquid Natural Rubber ◽  
New Type

A new type of polyurethane (PU) has been synthesized by using hydroxyl terminated liquid natural rubber (HTNR) and poly(e-caprolactone) (PCL) as a soft segment and toluene-2,4 diisocyanate (TDI) as a hard segment. This PU becomes a biodegradable and recyclable polymer. The PU samples were synthesized by solution polymerization. TDI/PCL polymerization was prepared in order to determine the appropriate NCO:OH ratio which evaluated from the molecular weight of derived PU and the ratios which were able to form a polymeric film. The suitable NCO:OH ratios were 0.84:1 – 1.20:1 and the Mn of the derived PUs was 3000-5500 g/mol determined by using GPC. PU from PCL-HTNR block copolymer was synthesized by varying molar ratio between PCL and HTNR. HTNR has been synthesized by epoxidation reaction and chain cleavage of natural rubber. The Mn of HTNR was in the range of 1700-8000 g/mol. 1H-NMR and FTIR were used to determine the functional group in order to verify the prepared HTNR and PU. Glass transition temperature and thermal decomposition of PU samples were investigated by using DSC and TGA, respectively.

scholarly journals Fliposomes: pH-controlled Release from Liposomes Containing New trans-2-Morpholinocyclohexanol-based Amphiphiles that Perform a Conformational Flip and Trigger an Instant Cargo Release upon Acidification

2012 ◽  
Vol 7 (3) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Yu Zheng ◽  
Xin Liu ◽  
Nataliya M. Samoshina ◽  
Vyacheslav A. Chertkov ◽  
Andreas H. Franz ◽  
...  
Keyword(s):  
Molecular Size ◽  
Ph Sensitive ◽  
Molar Ratio ◽  
Ph Titration ◽  
Conformational Switch ◽  
Liposome Membrane ◽  
H Nmr ◽  
Rapid Release ◽  
New Type ◽  
Plausible Mechanism

A new type of pH-sensitive liposome (fliposomes) was designed based on the amphiphiles that are able to perform a pH-triggered conformational flip (flipids). This flip disrupts the liposome membrane and causes rapid release of the liposome cargo, specifically in the areas of increased acidity. The flipids (1-3) are equipped with a trans-2-morpholinocyclohexanol conformational switch. pH-Sensitive fliposomes containing one of these flipids, POPC and PEG-ceramide (molar ratio 50/45/5) were constructed and characterized. These compositions were stable at 4oC and pH 7.4 for several months. Fliposomes loaded with ANTS/DPX demonstrated an unusually quick content release (in a few seconds) at pH below 5.5, which was more efficient in the case of flipid 1 with the shorter linear C12-tails. The pH-titration curve for the fliposome leakage paralleled the curve for the acid-induced conformational flip of 1-3 studied by 1H NMR. A plausible mechanism of the pH-sensitivity starts with an acid-triggered conformational flip of 1, 2 or 3, which changes the molecular size and shape, shortens the lipid tails, and perturbs the liposome membrane resulting in the content leakage.

Preparation and Characterization of Hyperbranched Silicone Oil by Hydrosilylation Reaction

2013 ◽  
Vol 395-396 ◽  
pp. 363-366
Author(s):  
Zhu Liu ◽  
Hua Shi Liu ◽  
Rui Fang Guan ◽  
Chuan Jian Zhou
Keyword(s):  
Dynamic Viscosity ◽  
High Performance ◽  
Silicone Oil ◽  
Raw Materials ◽  
Molar Ratio ◽  
Straight Chain ◽  
Hydrosilylation Reaction ◽  
H Nmr ◽  
Structures And Properties

Hyperbranched silicone oil was prepared using low-polyhydrosiloxane and vinyl terminated methylphenyl silicone oil as the raw materials through hydrosilylation reaction. The structures and properties of hyperbranched silicone oil were characterized through 1H NMR, TG and dynamic viscosity. The influence on synthesis of hyperbranched silicone oil was discussed, which was caused by ratio of different raw materials. When molar ratio of Si-H bond and Si-Vi bond of raw materials was 3.5:1 (mol), the reaction degree of hyperbranched silicone oils double bond was as high as 80%. At room temperature and 100°C, comparing the dynamic viscosity of hyperbranched silicone oil and straight chain silicone oil, we found that viscosity decrease rate of hyperbranched silicone oil was obviously lower. TG curve of hyperbranched silicone oil and straight chain silicone oil also certified that the hyperbranched silicone oil has higher thermal stability than the straight chain phenyl silicone oil. Therefore hyperbranched silicone oil is more suitable for the preparation of high-performance elastic clay than straight chain silicone oil.

scholarly journals Production and Characterization of Biodiesel Using Nonedible Castor Oil by Immobilized Lipase fromBacillus aerius

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Sunil Kumar Narwal ◽  
Nitin Kumar Saun ◽  
Priyanka Dogra ◽  
Ghanshyam Chauhan ◽  
Reena Gupta
Keyword(s):  
Castor Oil ◽  
Immobilized Lipase ◽  
Chemical Reactor ◽  
Molar Ratio ◽  
Free System ◽  
H Nmr ◽  
Solvent Free System ◽  
Substrate Molar Ratio ◽  
Optimized Conditions

A novel thermotolerant lipase fromBacillus aeriuswas immobilized on inexpensive silica gel matrix. The immobilized lipase was used for the synthesis of biodiesel using castor oil as a substrate in a solvent free system at 55°C under shaking in a chemical reactor. Several crucial parameters affecting biodiesel yield such as incubation time, temperature, substrate molar ratio, and amount of lipase were optimized. Under the optimized conditions, the highest biodiesel yield was up to 78.13%. The characterization of synthesized biodiesel was done through FTIR spectroscopy,1H NMR spectra, and gas chromatography.

scholarly journals Synthesis and Characterization of Liquid Natural Rubber as Impact Modifier for Epoxy Resin

2014 ◽  
Vol 55 ◽  
pp. 129-137 ◽  
Author(s):  
A.B. Ben Saleh ◽  
Z.A. Mohd Ishak ◽  
A.S. Hashim ◽  
W.A. Kamil ◽  
U.S. Ishiaku
Keyword(s):  
Natural Rubber ◽  
Epoxy Resin ◽  
Synthesis And Characterization ◽  
Liquid Natural Rubber ◽  
Impact Modifier

Preparation and characterization of a new type of symmetrical dicyclopentyl substituted cucurbit[6]uril

2021 ◽  
pp. 095400832110231
Author(s):  
Jun Zheng ◽  
Lin Zhang ◽  
Xinan Yang ◽  
Ye Meng ◽  
Yanmei Jin ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrochloric Acid ◽  
Honeycomb Structure ◽  
Monoclinic Crystal System ◽  
Monoclinic Crystal ◽  
X Ray ◽  
H Nmr ◽  
Group A ◽  
New Type

A symmetrical dicyclopentyl substituted cucurbit[6]uril (CyP2Q[6]) was synthesized, and crystallized under the conditions of 3 mol/L hydrochloric acid solution and the induction of ZnCl2. The crystal structure was characterized by X-ray single crystal diffractometer, 1H NMR and MS, and the results show that the crystal belongs to the monoclinic crystal system with P21/n space group, a = 13.095 (2), b = 33.002 (6), c = 15.770 (3), α = 90°, β = 102.828(5)°, γ = 90°, Z = 4, and a macroporous honeycomb structure appears in the crystal.

Synthesis and Characterization of 2-Di-methyl Amino Ethyl Laurate Betaine Surfactant

2021 ◽  
Vol 58 (3) ◽  
pp. 220-229
Author(s):  
Rutu Parikh ◽  
Shital Godse ◽  
Nitin Pawar ◽  
Amit Pratap
Keyword(s):  
Coconut Oil ◽  
Enzyme Concentration ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Enzymatic Esterification ◽  
H Nmr ◽  
Temperature Time ◽  
By Products ◽  
Betaine Ester

Abstract The growing need for sustainable natural-based surfactants from green chemistry has led to syntheses of surfactants without the use of solvents and without the generation of by-products when milder manufacturing processes are used. The zwitterionic betaine ester surfactants are derived from natural renewable sources and are biodegradable. In this research, the betaine ester surfactant 2-di-methylaminoethyllaurate betaine was synthesized from 2-di-methylaminoehanol and lauric acid derived from coconut oil in a three-step chemo-enzymatic esterification reaction. The enzymatic process was optimized in terms of operating parameters such as temperature, time, molar ratio and enzyme concentration, resulting in a yield of 87.91%. Structural analysis of the intermediate 2-di-methylaminoethyl laurate as well as the final product 2-di-methylaminoethyl laurate betaine was carried out with FTIR and 1H NMR. The surfactant properties of the betaine were also determined and showed that the betaine can be used as a co-surfactant in many cosmetic and personal care products.

Synthesis and characterization of cellulose acetate naphthoate with good ultraviolet and chemical resistance

e-Polymers ◽  
2017 ◽  
Vol 17 (4) ◽  
pp. 333-340 ◽  
Author(s):  
Jun Song ◽  
Mei Liu ◽  
Zhanping Yang ◽  
Songwei Xu ◽  
Bowen Cheng ◽  
...  
Keyword(s):  
Cellulose Acetate ◽  
Chemical Structure ◽  
Chemical Resistance ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Cellulose Diacetate ◽  
H Nmr ◽  
Ultraviolet Resistance ◽  
Acid Catalyzed

AbstractCommercial cellulose diacetate with a degree of substitution (DS) of 2.45 was partly deacetylated to cellulose acetate (CA) with different DSs by acid-catalyzed hydrolysis and then reacted with 1-naphthoyl chloride (NpCl) to synthesize CA naphthoate (CANp). Fourier transform infrared and 1H-NMR were used to characterize the chemical structure of CANp. The DS of naphthoate moiety (DSCANp) could be varied from 0.18 to 0.98 by adjusting the molar ratio of –OH in CA unit to NpCl, the DS of CA (DSCA), and the reaction time and temperature. When DSCA was 2.01 and the molar ratio was 1:6, the maximum DSCANp of the product was achieved after a reaction at 80°C for 2 h. With the increase of DSCANp, the thermal stability decreased slightly whereas the anti-ultraviolet property was enhanced. Moreover, the obtained films containing CANp exhibited good ultraviolet resistance as well as chemical resistance.

Preparation and Characterization of a New Type Lithium Hexafluorophosphate Complex

2011 ◽  
Vol 236-238 ◽  
pp. 552-555 ◽  
Author(s):  
Hai Lan Yang ◽  
Zhi Ye Zhang ◽  
Lin Yang ◽  
Ben He Zhong ◽  
Ling Yun Li ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Chemical Analysis ◽  
Lithium Ion Battery ◽  
Lithium Fluoride ◽  
Lithium Ion ◽  
Molecular Formula ◽  
H Nmr ◽  
New Type ◽  
Lithium Hexafluorophosphate

In this paper, a new type lithium hexafluorophosphate (LiPF6) complex was prepared with a new method using phosphorus pentachlorine (PCl5), lithium fluoride (LiF) and 1,2-dimethoxyethane (C4H10O2). The structure of the complex was carefully characterized by FTIR, TG-DTG,1H NMR and31P NMR. FTIR results indicate that the synthesized complex is consisted of LiPF6and C4H10O2. Chemical analysis shows that the content of LiPF6in the complex is about 45%, which could infer that the mole ratio of LiPF6and LiPF6(C4H10O2)2in the complex is 1:2. The results of1H NMR and31P NMR further confirm the composition of the complex and determine the structure. The molecular formula of the LiPF6complex is LiPF6(C4H10O2)2. Thermal analysis shows that the strong decomposition peaks of the complex appear at 75°C and 175°C. LiPF6(C4H10O2)2may be used in the electrolyte of the lithium ion battery which 1,2-dimethoxyethane is permitted or broke down into LiPF6after further preparation.

scholarly journals Synthesis and Spectroscopic Characterization of Lead(II)bis{O,O'-ditolyldithiophosphates} and their Adducts with 2,2'-Bipyridyl and 1,10-Phenanthroline

2011 ◽  
Vol 8 (s1) ◽  
pp. S113-S118
Author(s):  
Disha Jain Alok Chaturvedi ◽  
R.K. Upadhayay
Keyword(s):  
Spectroscopic Characterization ◽  
Spectroscopic Studies ◽  
Ammonium Salts ◽  
Molar Ratio ◽  
Spectroscopic Techniques ◽  
Lead Atom ◽  
H Nmr

The reaction of lead(II) dichloride with ammonium salts ofO,O'-ditolyldithiophosphoric acid have been carried out in 1:2 molar ratio by refluxing in benzene. These compounds have been further used to synthesize the adduct of the type lead(II)bis{O,O'-ditolyldithiophosphates}.2,2'-bipyridyl and lead(II)bis {O,O'-ditolyldithiophosphates}.1,10-phenanthroline by the reaction of lead(II)bis{O,O'-ditolyldithiophosphates} and 2,2'-bipyridyl and 1,10-phenanthro-line in the presence of unimolar dichloromethane and ethanol. All these complexes have been characterized by spectroscopic techniques such as IR,1H NMR and31P NMR. On the basis of spectroscopic studies tetracoordinated nature of lead atom in ditolyldithiophosphates complexes and hexacoordinated nature in their adducts have been established.

Synthesis and Characterization of Biomedical Aliphatic Polyurethane Material

2014 ◽  
Vol 809-810 ◽  
pp. 520-526
Author(s):  
Rong Zhu ◽  
Zong Rui Zhang ◽  
Ming Bei Zhu ◽  
Xin Yu Wang
Keyword(s):  
Mechanical Properties ◽  
Hard Segment ◽  
Soft Segment ◽  
Molar Ratio ◽  
Dibutyltin Dilaurate ◽  
Biomedical Material ◽  
Prepared Material ◽  
The Relationship ◽  
Poly Carbonate

Biomedical transparent poly(carbonate-urethane) elastomers were synthesized by melting pre-polymer method, using 4,4’-methylenebis (cyclohexyl isocyanate)(H12MDI) and chain extender (butadiene)(BDO) as hard segment, poly(1,6-hexanediol) carbonate diols(PCDL) as soft segment, and dibutyltin dilaurate as catalyst.The effects of molar ratio of the reactants on mechanical properties of PCU were studied and the relationship between micro-phase separation structure and properties was analyzed by the contact angle determination, total reflection fourier transform infrared spectrography(ATR-FTIR), differential scanning calorimeter(DSC),gel permeation chromatograph (GPC), mechanical property test. The comparative analysis was made between the prepared material and commercial medical polyurethane materials, showing the prepared poly(carbonate-urethane) elastomers was better in mechanical properties. As a elastic biomedical material, it has a great potential for developments and applications in biomedical materials.

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