Effects of Monomer Compatibility on Sizing Performance of Chitosan-g-P(MA-co-AM)

2021 ◽  
Vol 8 (6) ◽  
pp. 58-66
Author(s):  
Manli Li ◽  
Shuangshuang Wang ◽  
Enqi Jin ◽  
Bing Yu ◽  
Zhiyong Qiao
Keyword(s):  
Methyl Acrylate ◽  
Redox System ◽  
Molar Ratio ◽  
Application Performance ◽  
Overall Performance ◽  
Feed Molar Ratio

To impart good application performance to chitosan (CS) sizes for high polyester content warp yarns, methyl acrylate (MA) and acrylamide (AM) monomers, with a variation in feed molar ratio from 1:9 to 4:6, were grafted onto the molecular chains of native CS to obtain CS-g-P(MA-co-AM) products, with similar grafting ratios through a K2S2O8-NaHSO3 redox system. Effects of monomer compatibility of MA and AM on sizing performance of the CS-g-P(MA-co-AM) for high polyester content warp were studied. Grafting MA and AM with rational compatibility onto the molecular chains of CS is an effective method to improve the application performance of CS sizes. In view of the overall performance of the CS-g-P(MA-co-AM) sizes, the appropriate feed molar ratio of MA/AM should be 3:7.

Thermal analysis and melt spinnability of poly(acrylonitrile-co-methyl acrylate) and poly(acrylonitrile-co-dimethyl itaconate) copolymers

2017 ◽  
Vol 88 (13) ◽  
pp. 1479-1490 ◽  
Author(s):  
Syang-Peng Rwei ◽  
Tun-Fun Way ◽  
Whe-Yi Chiang ◽  
Jen-Chun Tseng
Keyword(s):  
Thermal Analysis ◽  
Carbon Fiber ◽  
Low Temperature ◽  
Melting Temperature ◽  
Methyl Acrylate ◽  
Dwell Time ◽  
Molar Ratio ◽  
Poly Acrylonitrile ◽  
Feed Molar Ratio ◽  
Dimethyl Itaconate

This work investigated the cyclization possibility and melt spinnability of carbon fiber precursors, poly(acrylonitrile-co-methyl acrylate) (AN/MA) and poly(acrylonitrile-co-dimethyl itaconate) (AN/DMI). The onset temperature of cyclization of the AN/DMI copolymer is lower than that of the AN/MA copolymer and also the polyacrylonitrile (PAN) homopolymer. The enthalpy ( ΔH) of the AN/DMI copolymer is about 3–4 times that of the PAN homopolymer and about 1.8 times that of the AN/MA copolymer, indicating that the degree of cyclization of the AN/DMI copolymer is relatively higher. The melt dwell time of the AN/DMI copolymer is increased to about 3–5 times that of the AN/MA copolymer, especially when synthesized with a feed molar ratio of AN/DMI = 85/15. The AN/DMI copolymer (AN/DMI = 85/15) has the longest melt dwell time, 24.8 min, at the lowest melting temperature, 190oC, among all the PAN-related copolymers synthesized herein. Furthermore, the AN/DMI copolymer (AN/DMI = 85/15) can be rapidly cyclized at the cyclization temperature of 260℃, which is 25℃ lower than that of the AN/MA copolymer (AN/MA = 85/15). In short, this work demonstrates that the carbon fiber precursor made by the AN/DMI copolymer (AN/DMI = 85/15) will be superior to that of the AN/MA copolymer (AN/MA = 85/15) with respect to the melt spinnability and cyclization at low temperature.

Synthesis of AM-co-NVP and Thermal Stability in Hostile Saline Solution

2012 ◽  
Vol 602-604 ◽  
pp. 1349-1354 ◽  
Author(s):  
Rui Liu ◽  
Wan Fen Pu ◽  
Qin Peng ◽  
Feng Sheng Yao
Keyword(s):  
Thermal Stability ◽  
Saline Solution ◽  
Heat Stability ◽  
Structure Characterization ◽  
Vinyl Pyrrolidone ◽  
Molar Ratio ◽  
Mass Ratio ◽  
Excellent Thermal Stability ◽  
Hydrolyzed Polyacrylamide ◽  
Feed Molar Ratio

copolymer preparation; structure characterization; thermal stability; brines solution. Abstract. The copolymer (AM-co-NVP) of acrylamide (AM) and vinyl pyrrolidone (NVP) was carried out in the presence of 2,2'-azobis[2-methylpropionamidine] dihydrochloride（V50）as initiator by free radical polymerization. The copolymer was characterized by its chemical structure with Fourier transform infrared spectroscopy (FTIR). The heat resistance of AM-co-NVP at 100°C and 120°C in harsh saline solution with high mineralized concentration ranging from 5×104 mg/L to 20×104 mg/L containing 2.5% (mass ratio) CaCl2, 2.5% (mass ratio) MgCl2 and 95% NaCl (mass ratio) was investigated. The experimental results indicate that AM-co-NVP has excellent thermal stability in saline solution compared to partially hydrolyzed polyacrylamide (HPAM). What is more, the copolymer exhibited the most perfect thermal tolerance in high divalent saline solution when the feed molar ratio of AM and NVP is 91.5 to 8.5. The microstructures of the copolymer samples after thermal aging in hostile environment captured by scanning electron microscope (SEM）further proved the NVP monomer was effectively introduced leading to the copolymer favorable heat stability in particularly high mineralized solution.

Resin Material Used in Methyl Acrylate Hydrolysis Reaction

2014 ◽  
Vol 1035 ◽  
pp. 307-312 ◽  
Author(s):  
Ya Ping Li ◽  
Quan Huo ◽  
Cun Cun Zuo ◽  
Sha Sha Cao ◽  
Er Qiang Wang
Keyword(s):  
Experimental Data ◽  
Methyl Acrylate ◽  
Exchange Resin ◽  
Cation Exchange Resin ◽  
Reaction System ◽  
Ion Exchange Resin ◽  
High Energy ◽  
Molar Ratio ◽  
Resin Catalyst ◽  
Hydrolysis Of

In this work, the ion exchange resin catalyst named D072 were used in the hydrolysis of a methyl acrylate to acrylic acid and methanol firstlyand chemical equilibrium would be achieved during the process of the reversible reaction system. The influences of parameters such as dosage of catalyst, initial reactants molar ratio and reaction temperature were investigated. Meanwhile, the reusability of cation-exchange resin was studied, and no phenomenon of deactivation was found with using of reused catalyst. Moreover, the experimental data were analyzed by the pseudo-homogeneous (PH) model and the hydrolysis dynamics equation of methyl acrylate was obtained and found that the activation energy of the reaction was 118.37 KJ/mol in the presence of D072. Based on the result, high energy would be needed to the hydrolysis of methyl acrylate in using D072 resin as catalyst.

Nickel and cobalt phosphides as effective catalysts for oxygen removal of dibenzofuran: role of contact time, hydrogen pressure and hydrogen/feed molar ratio

2015 ◽  
Vol 5 (6) ◽  
pp. 3403-3415 ◽  
Author(s):  
A. Infantes-Molina ◽  
E. Gralberg ◽  
J. A. Cecilia ◽  
Elisabetta Finocchio ◽  
E. Rodríguez-Castellón
Keyword(s):  
Catalytic Activity ◽  
Contact Time ◽  
Hydrogen Pressure ◽  
Oxygen Removal ◽  
Molar Ratio ◽  
Metal Loading ◽  
Molar Ratios ◽  
Feed Molar Ratio

The catalytic activity of nickel and cobalt phosphides, with a metal loading of 5 wt.%, supported on silica was investigated in the hydrodeoxygenation reaction (HDO) of dibenzofuran (DBF) as a model oxygenated compound at different contact times, H2 pressures and H2/DBF molar ratios.

Grafting of Methyl Acrylate and Methyl Methacrylate onto Jute fiber: Physico-Chemical Characteristics of the Grafted Jute

2013 ◽  
Vol 8 (3) ◽  
pp. 155892501300800 ◽  
Author(s):  
Ibrahim H. Mondal
Keyword(s):  
Methyl Methacrylate ◽  
Methyl Acrylate ◽  
Graft Copolymerization ◽  
Monomer Concentration ◽  
Redox System ◽  
Jute Fiber ◽  
Lower Amount ◽  
Physico Chemical ◽  
Dye Absorption ◽  
Graft Yield

The graft copolymerization of methyl acrylate and methyl methacrylate vinyl monomers onto jute fiber using potassium persulfate and ferrous sulfate redox system was investigated in an aqueous medium. Optimized reaction conditions for the graft copolymerization were established for parameter variables, of monomer concentration, initiator concentration, catalyst concentration, reaction time, and reaction temperature. The grafting degrees were found to depend on the above mentioned variables. A maximum graft yield of 17.3% for MA and 19.4% for MMA was obtained under effective optimized conditions for grafting. The attachment of the monomer on the grafted fiber was confirmed by FTIR studies. Dyeing was affected by monomer characteristics, and due to the development of hydrophobic nature on jute fiber by grafting, a lower amount of dye absorption occurred. Grafting has a favorable influence on tenacity, color fastness, and other properties of jute fiber.

Process Intensification of Methane Production via Catalytic Hydrogenation in the Presence of Ni-CeO2/Cr2O3 Using a Micro-Channel Reactor

Catalysts ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1224
Author(s):  
Vut Tongnan ◽  
Youssef Ait-lahcen ◽  
Chuthamas Wongsartsai ◽  
Chalempol Khajonvittayakul ◽  
Nuchanart Siri-Nguan ◽  
...  
Keyword(s):  
Activation Energy ◽  
Process Intensification ◽  
Catalytic Performance ◽  
Molar Ratio ◽  
Micro Channel ◽  
Co2 Conversion ◽  
Channel Reactor ◽  
Mechanistic Pathway ◽  
Slight Amount ◽  
Feed Molar Ratio

A slight amount of Cr2O3 segregation in 40 wt% NiO/Ce0.5Cr0.5O2 was presented at the surface. The best catalytic performance towards the reaction was achieved at 74% of CO2 conversion and 100% CH4 selectivity at 310 °C, the reactant (H2/CO2) feed molar ratio was 4, and the WHSV was 56,500 mlN·h−1·g−1cat. The mechanistic pathway was proposed through carbonates and formates as a mediator during CO2 and H2 interaction. Activation energy was estimated at 4.85 kJ/mol, when the orders of the reaction were ranging from 0.33 to 1.07 for nth-order, and 0.40 to 0.53 for mth-order.

scholarly journals A feasible synthetic strategy for three-armed star poly(ester amine) via Michael addition polymerization

e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Wei Yang ◽  
Cai-Yuan Pan
Keyword(s):  
Molecular Weight ◽  
Michael Addition ◽  
Monomer Concentration ◽  
Gel Permeation Chromatography ◽  
Molar Ratio ◽  
Glycol Diacrylate ◽  
H Nmr ◽  
Synthetic Strategy ◽  
Addition Polymerization ◽  
Feed Molar Ratio

AbstractThree-armed star-shaped poly(ester amine) was synthesized by Michael addition polymerizations of equal molar ratio of ethylene glycol diacrylate (EGDA) and piperazine (PZ) in the presence of a small amount of multifunctional monomer, 1,3,5-triacryloylhexa-hydro-1,3,5-triazine (TT) in CHCl3. When the polymerization proceeded almost completely, the molecular weight of the polymers formed were determined by the feed molar ratio of difunctional monomer to multifunctional monomer, and the molecular weight distribution (Mw/Mn) approached the theoretical value (Mw/Mn =1+1/f). The mechanism of the polymerization was investigated by 1H NMR and Gel permeation chromatography (GPC). The monomer concentration and the molar ratio of difunctional monomers/multifunctional monomer played an important role in the polymerization.

scholarly journals A Theoretical Analysis on a Multi-Bed Pervaporation Membrane Reactor during Levulinic Acid Esterification Using the Computational Fluid Dynamic Method

Membranes ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 635
Author(s):  
Milad Ghahremani ◽  
Kamran Ghasemzadeh ◽  
Elham Jalilnejad ◽  
Adolfo Iulianelli
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Levulinic Acid ◽  
Membrane Reactor ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
Water Removal ◽  
Feed Flow Rate ◽  
Pervaporation Membrane ◽  
Feed Molar Ratio

Pervaporation is a peculiar membrane separation process, which is considered for integration with a variety of reactions in promising new applications. Pervaporation membrane reactors have some specific uses in sustainable chemistry, such as the esterification processes. This theoretical study based on the computational fluid dynamics method aims to evaluate the performance of a multi-bed pervaporation membrane reactor (including poly (vinyl alcohol) membrane) to produce ethyl levulinate as a significant fuel additive, coming from the esterification of levulinic acid. For comparison, an equivalent multi-bed traditional reactor is also studied at the same operating conditions of the aforementioned pervaporation membrane reactor. A computational fluid dynamics model was developed and validated by experimental literature data. The effects of reaction temperature, catalyst loading, feed molar ratio, and feed flow rate on the reactor’s performance in terms of levulinic acid conversion and water removal were hence studied. The simulations indicated that the multi-bed pervaporation membrane reactor results to be the best solution over the multi-bed traditional reactor, presenting the best simulation results at 343 K, 2 bar, catalyst loading 8.6 g, feed flow rate 7 mm3/s, and feed molar ratio 3 with levulinic acid conversion equal to 95.3% and 91.1% water removal.

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