scholarly journals Synthesis and Characterization of Polyphosphazenes Modified with Hydroxyethyl Methacrylate and Lactic Acid

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Evelyn Carolina Martínez Ceballos ◽  
Ricardo Vera Graziano ◽  
Gonzalo Martínez Barrera ◽  
Oscar Olea Mejía
Keyword(s):  
Lactic Acid ◽  
Ring Opening ◽  
Room Temperature ◽  
Block Structure ◽  
Ring Opening Polymerization ◽  
Synthesis And Characterization ◽  
Poly Lactic Acid ◽  
Hydroxyethyl Methacrylate ◽  
H Nmr

Poly(dichlorophosphazene) was prepared by melt ring-opening polymerization of the hexachlorocyclotriphosphazene. Poly[bis(2-hydroxyethyl-methacrylate)-phosphazene] and poly[(2-hydroxyethyl-methacrylate)-graft-poly(lactic-acid)-phosphazene] were obtained by nucleophilic condensation reactions at different concentrations of the substituents. The properties of the synthesized copolymers were assessed by FTIR,1H-NMR and31P-NMR, thermal analysis (DSC-TGA), and electron microscopy (SEM). The copolymers have a block structure and show twoTg's below room temperature. They are stable up to a temperature of 100°C. The type of the substituents attached to the PZ backbone determines the morphology of the polymers.

scholarly journals Synthesis and characterization of copoly(L-lactic acid-caprolactone) and its stereo-effect with poly D-lactic acid and biodegradability

2012 ◽  
Vol 47 (2) ◽  
pp. 203-210
Author(s):  
M Amirul Hoque ◽  
A Nakayama ◽  
HP Nur ◽  
SK Raya ◽  
MM Rahman ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Ring Opening ◽  
Treatment Method ◽  
Ring Opening Polymerization ◽  
Effect Of Temperature ◽  
Feed Ratio ◽  
Synthesis And Characterization ◽  
Enzymatic Method ◽  
Sludge Treatment

Random copolymerizations of L-Lactide with ?-Caprolactone by ring opening polymerization reactions were carried out. A number of copolymers were formed and observed that any composition of copolymer can be formed by changing the feed ratio of the respective monomers. The effect of temperature and time in copolymerization reaction were studied. For their characterization, NMR, IR, DSC and GPC were measured. The stereo-effect of the lactic acid based biodegradable polymers and copolymers for improve thermo-mechanical properties were studied. The obtained copolymers also show stereo-effect like homopolymer. The biodegradability of obtained polymers, copolymers and stereocomplex were studied in three different biodegradation methods; e.g., Enzymatic method, Composting method and Activated Sludge treatment method; and compared to each other. DOI: http://dx.doi.org/10.3329/bjsir.v47i2.11453 Bangladesh J. Sci. Ind. Res. 47(2), 203-210, 2012

Synthesis and characterization of star polylactide by ring-opening polymerization of l-lactic acid O-carboxyanhydride

2014 ◽  
Vol 71 (6) ◽  
pp. 1331-1347 ◽  
Author(s):  
Mingwei Yuan ◽  
Zhengguo He ◽  
Hongli Li ◽  
Lin Jiang ◽  
Minglong Yuan
Keyword(s):  
Lactic Acid ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Synthesis And Characterization

Synthesis and Characterization of Poly(Lactic Acid)-Grafted Natural Rubber by Reactive Melt-Blending Technique

2018 ◽  
Vol 382 ◽  
pp. 7-11
Author(s):  
Yodsathorn Wongngam ◽  
Cattaleeya Pattamaprom
Keyword(s):  
Lactic Acid ◽  
Natural Rubber ◽  
Ring Opening ◽  
Degree Of Polymerization ◽  
Hydroxyl Group ◽  
Synthesis And Characterization ◽  
Poly Lactic Acid ◽  
Esterification Reaction ◽  
Ring Opening Reaction

This study investigated the synthesis and characterization of poly(lactic acid)-grafted natural rubber (PLA-g-NR) in molten state. The grafting was carried out in an internal mixer without and with the presence of tin octoate catalyst (TO). The grafting of lactide onto NR was carried out by using maleic anhydride (MA) as a linker. The FTIR and 1H-NMR spectra revealed new peaks for the MA-grafted NR (NR-g-MA) and PLA indicating that MA was grafted onto NR and that LA was successfully polymerized into PLA. It was also found that MA grafted onto NR could assist as a linker for connecting PLA with NR via esterification reaction between hydroxyl group (OH) at the end chain of PLA and carboxylic group (COOH) from ring opening reaction of MA. Moreover, the decrease of residual LA peak in FTIR spectra suggested that the presence of TO catalyst in the reactive blend promoted higher degree of polymerization of PLA from ring opening reaction of LA.

scholarly journals Synthesis and characterization of different soybean oil-based polyols with fatty alcohol and aromatic alcohol

e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 491-499
Author(s):  
Fukai Yang ◽  
Hao Yu ◽  
Yuyuan Deng ◽  
Xinyu Xu
Keyword(s):  
Molecular Weight ◽  
Soybean Oil ◽  
Retention Time ◽  
Ring Opening ◽  
Isoamyl Alcohol ◽  
Synthesis And Characterization ◽  
Intermolecular Force ◽  
H Nmr ◽  
Epoxy Groups

Abstract In this article, five kinds of soybean oil-based polyols (polyol-E, polyol-P, polyol-I, polyol-B, and polyol-M) were prepared by ring-opening the epoxy groups in epoxidized soybean oil (ESO) with ethyl alcohol, 1-pentanol, isoamyl alcohol, p-tert-butylphenol, and 4-methoxyphenol in the presence of tetrafluoroboric acid as the catalyst. The SOPs were characterized by FTIR, 1H NMR, GPC, viscosity, and hydroxyl numbers. Compared with ESO, the retention time of SOPs is shortened, indicating that the molecular weight of SOPs is increased. The structure of different monomers can significantly affect the hydroxyl numbers of SOPs. Due to the large steric hindrance of isoamyl alcohol, p-hydroxyanisole, and p-tert-butylphenol, SOPs prepared by these three monomers often undergo further dehydration to ether reactions, which consumes the hydroxyl of polyols, thus forming dimers and multimers; therefore, the hydroxyl numbers are much lower than polyol-E and polyol-P. The viscosity of polyol-E and polyol-P is much lower than that of polyol-I, polyol-B, and polyol-M. A longer distance between the molecules and the smaller intermolecular force makes the SOPs dehydrate to ether again. This generates dimer or polymers and makes the viscosity of these SOPs larger, and the molecular weight greatly increases.

Synthesis and Characterization of Polydimethylsiloxane (PDMS) with Medium Viscosity via Ring-Opening Polymerization

2021 ◽  
Vol 1028 ◽  
pp. 346-351
Author(s):  
Soni Setiadji ◽  
Zulfi Mofa Agasa ◽  
Diba G Auliya ◽  
Fitrilawati ◽  
Norman Syakir ◽  
...  
Keyword(s):  
Ring Opening ◽  
Vitreoretinal Surgery ◽  
High Viscosity ◽  
Ring Opening Polymerization ◽  
Vitreous Humour ◽  
Synthesis And Characterization ◽  
Low Viscosity ◽  
A Value ◽  
Medium Viscosity

Duration of use and injectability are external factors for Polydimethylsiloxane (PDMS) that needs to be considered when PDMS utilized as a vitreous substituted liquid in vitreoretinal surgery. In general, PDMS which has been used as a substitute for vitreous humour is PDMS with a low viscosity in the value about 1000 cSt and a high viscosity at a value of about 5000 cSt. Various deficiencies have been encountered from low and high viscosity of PDMS, causing research to be continued to obtain PDMS which has suitable properties as a substitute for vitreous humour. One of them is research to obtain medium viscosity of PDMS with a viscosity value of about 2000 cSt. Here, we reported synthesis and characterization of PDMS with medium viscosity in ranges from 1800 to 2600 mPas. PDMS was synthesized through Ring-Opening Polymerization (ROP) pathway using the monomer of Octamethylcyclotetrasiloxane (D4) and the chain terminator of Hexamethyldisiloxane (MM). Various concentrations of potassium hydroxide (KOH) of 3, 4, 6 and 8 %(w/v) were applied as initiator to form gel of PDMS. All synthesized PDMS samples were identified to have viscosity values of 1800-2600 mPas, refractive index values of 1.4042-1.4044 and surface tension values of 22-23 mN/m. Meanwhile, the results of Fourier-Transform Infrared (FTIR) measurement showed that the absorption peaks were similar to that of our previous report.

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