scholarly journals Investigation on the Synthesis Process of Bromoisobutyryl Esterified Starch and Its Sizing Properties: Viscosity Stability, Adhesion and Film Properties

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1936
Author(s):  
Wei Li ◽  
Jie Wu ◽  
Zhengqiao Zhang ◽  
Lanjuan Wu ◽  
Yuhao Lu

To confirm the suitable synthesis process parameters of preparing bromoisobutyryl esterified starch (BBES), the influences of the synthesis process parameters—amount of 2-bromoisobutyryl bromide (BIBB), amount of catalyst (DMAP), reaction temperature and reaction time—upon the degree of substitution (DS) were investigated. Then, to produce a positive effect on the properties of graft copolymers of BBES prepared in the near future, a series of BBES samples were successfully prepared, and their sizing properties, such as apparent viscosity and viscosity stability, adhesion, and film properties, were examined. The BBES granules were characterized by Fourier transform infra-red spectroscopy and scanning electron microscopy. The adhesion was examined by determining the bonding forces of the sized polylactic acid (PLA) and polyester roving. The film properties were investigated in terms of tensile strength, breaking elongation, degree of crystallinity, and cross-section analysis. The results showed that a suitable synthesis process of BBES was: reaction time of 24 h, reaction temperature of 40 °C, and 0.23 in the molar ratio of 4-dimethylaminopyridine to 2-bromoisobutyryl bromide. The bromoisobutyryl esterification played the important roles in the properties of the starch, such as paste stabilities of above 85% for satisfying the requirement in the stability for sizing, improvement of the adhesion to polylactic acid and polyester fibers, and reduction of film brittleness. With rising DS, bonding forces of BBES to the fibers increased and then decreased. BBES (DS = 0.016) had the highest force and breaking elongation of the film. Considering the experimental results, BBES (DS = 0.016) showed potential in the PLA and polyester sizing, and will not lead to a negative influence on the properties of graft copolymers of BBES.

Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1110 ◽  
Author(s):  
Wei Li ◽  
Zhenzhen Xu ◽  
Zongqian Wang ◽  
Jian Xing

To investigate the influences of quaternization/hydroxypropylsulfonation on viscosity stability, adhesion to fibers and film properties of oxidized tapioca starch (OTS) for ameliorating its end-use ability in applications such as warp-sizing and paper-making, a series of quaternized and hydroxypropylsulfonated OTS (QHOTS) samples were synthesized by simultaneous quaternization and hydroxypropylsulfonation of OTS with N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride (CHPTAC) and 3-chloro-2-hydroxy-1-propanesulfonic acid sodium salt (CHPS-Na). The QHOTS granules were characterized by Fourier transform infra-red spectroscopic and scanning electron microscope techniques. Apparent viscosity and viscosity stability were determined, and adhesion was evaluated by measuring the bonding force of starch to the fibers. Film properties were also estimated in terms of tensile strength, breaking elongation, bending endurance, degree of crystallinity, and moisture regain. It was showed that quaternization/hydroxypropylsulfonation was capable of obviously improving viscosity stability of gelatinized OTS paste, enhancing bonding forces of OTS to cotton and polylactic acid (PLA) fibers, increasing breaking elongation, bending endurance and moisture regain of film and decreasing its tensile strength and degree of crystallinity, thereby obviously stabilizing paste viscosity, improving adhesion to fibers and lessening film brittleness. Increasing the level of quaternization/hydroxypropylsulfonation favored improvement in the stability, enhancement in adhesion and decrease in brittleness. The QHOTS showed potential in the applications of cotton and PLA sizing.


2012 ◽  
Vol 550-553 ◽  
pp. 10-15 ◽  
Author(s):  
Jing Chen Wang ◽  
Feng Xia Cui ◽  
Tao Li

With 2-keto-L-gulonic acid(2KLG) and methanol as raw materials, 98% concentrated sulfuric acid as catalyst, the methyl esterification reaction is occurred. Then with sodium carbonate as a transforming agent, a conversion reaction sodium carbonate is obtained. In this experiment, the effects of reaction time, reaction temperature and reactant ratio on conversion rate of sodium ascorbate were studied. The results showed that sodium carbonate as the reactant of lactonization reaction can effectively shorten the reaction time and improve reaction yield. By experiment under the optimum process conditions: the reaction temperature is 65 °C, reaction time is 150 minutes and the molar ratio of 2-keto-L-gu methyl to sodium carbonate is 1:0.6, the conversion rate reaches 98 % and the effect is better than with sodium bicarbonate as transforming agent.


Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1437
Author(s):  
Xiaoling Ren ◽  
Xinqian Shu ◽  
Haisheng Li ◽  
Jiushuai Deng ◽  
Peng Li ◽  
...  

In order to optimize the process parameters of Cd removal in the ZnSO4 production process and study the mechanism of Cd removal reaction, the response surface methodology was used to arrange Cd removal experiments and analyze the optimal production conditions, and the mechanism of Cd removal was studied using kinetics. The results show that the optimal process conditions for Cd removal are as follows: reaction temperature 55 °C, reaction time 13.43 min, and the zinc powder dosage should be 2.14 times that of Cd; the main effects of the three variables from large to small are zinc powder dosage, reaction temperature and reaction time; Cd removal is a second-order reaction, and the activation energy of the reaction is 29.6986 kJ/mol, so the reaction conforms to the diffusion control mechanism.


2020 ◽  
Vol 834 ◽  
pp. 16-23
Author(s):  
Pongchanun Luangpaiboon ◽  
Pasura Aungkulanon

Biodiesel was synthesized from direct transesterification of palm oil reacted with methanol in the presence of a suitable catalyst. There is a sequence of three consecutive reversible reactions for the transesterification process. These process parameters were optimized via the hybrid optimization approach of a conventional response surface method and artificial intelligence mechanisms from Sine Cosine and Thermal Exchange Optimization metaheuristics. The influential parameters and their combined interaction effects on the transesterification efficiency were established through a factorial designed experiments. In this study, the influential parameters being optimized to obtain the maximum yield of biodiesel were reaction temperature of 60–150°C, reaction time of 1–6 hours, methanol to oil molar ratio of 6:1–12:1 mol/mol and weight of catalyst of 1–10wt. %. On the first phase, the analysis of variance (ANOVA) revealed the reaction time as the most influential parameter on biodiesel production. Based on the experimental results from the hybrid algorithm via the SCO, it was concluded that the optimal biodiesel yield for the transesterification of palm oil were found to be 100°C for reaction temperature, 4 hours for reaction time, 10:1 wt/wt of ratio methanol to oil and 8% of weight of catalyst with 92.15% and 90.97% of biodiesel yield for expected and experimental values, respectively.


2011 ◽  
Vol 391-392 ◽  
pp. 1149-1152
Author(s):  
Qi Dong Yan ◽  
Jun Xu ◽  
Feng Xu

The paper has studied the process of using H2O2 as oxidant and tungsten acid as catalyst, catalytic oxidation synthesis process of cyclopentene to glutaraldehyde and explored the main influence factors of the reaction, including the reaction time, reaction temperature, catalyst dosage and solvent. Furthermore, the quantitative analysis and qualitative analysis of the product was characterized by gas chromatography. The optimum synthetic condition was as follows: tertiary butanol as solvent, tungsten acid: boron anhydride(mass ratio)=1:1, 30%H2O2 as oxidant, the reaction temperature 35°C, the reaction time 4h, the yield of glutaraldehyde yield was 46%.


2013 ◽  
Vol 826 ◽  
pp. 233-236
Author(s):  
Rui Mu ◽  
Cui Hua Ji

This study synthesized silicon emulsions by emulsion polymerization, mainly focused on how influencing factors including catalyst, emulsifier, reaction temperature and synthesis process could affect product conversion rate, appearance and molecular weight. The result showed that the conversion rate of the first 2 hours increased rapidly and became stable afterwards. Molecular weight increment was proportional to the extension of the reaction time. The silicon emulsions could achieve high convention rate and stability while applying 5% catalyst DBSA and 3% emulsifier (OP-10: SDS = 1:2) of Octmethyl cyclotetrasiloxane(D4) under an reaction temperature of 80 °C.


2021 ◽  
Author(s):  
Vaishali Mittal ◽  
Uttam Kumar Ghosh

Abstract Production of biodiesel from microalgae is gaining popularity since it does not compromise food security or the global economy. This article reports biodiesel production with Spirulina microalgae through nanocatalytic transesterification process. The nanocatalyst calcium methoxide Ca(OCH3)2 was synthesized using wet impregnation method and utilized to carry out the transesterification process. The nanocatalyst was characterized to evaluate its structural and spectral characteristics using different characterization techniques such as Thermogravimetric analysis (TGA), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and Brunaeur-Emmett-Teller(BET) measurement for surface area. The result demonstrates that calcium methoxide Ca(OCH3)2 possesses a high catalytic activity compared to a heterogeneous catalyst such as calcium oxide (CaO). The impact of several process parameters such as reaction temperature, the molar ratio of methanol to oil, catalyst concentration, and reaction time used in the transesterification process was optimized by employing central composite design(CCD) based response surface methodology(RSM). The polynomial regression equation of second order was obtained for methyl esters. The model projected a 99% fatty acid methyl esters (FAME) yield for optimal process parameters of reaction time 3hrs,3 wt.% of Ca(OCH3)2 catalyst loading, 80°C reaction temperature, and 30:1 methanol to oil molar ratio.


Minerals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 521 ◽  
Author(s):  
Bo Liu ◽  
Hongjuan Sun ◽  
Tongjiang Peng ◽  
Qian He

Ca-bentonite was used as the feedstock material for the synthesis of hydroxysodalite due to its high Al, Si content, good chemical reactivity, and natural abundance. A one-step method is proposed here to fabricate hydroxysodalite in a water bath at moderate temperature. The effects of the Na/Si molar ratio, Si/Al molar ratio, reaction time, and reaction temperature on the synthesis of hydroxysodalite have been systematically investigated here. The crystallizing phases and morphology of the synthetic products were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results showed that the Na/Si molar ratio and reaction temperature both played important roles in controlling the degree of crystallinity of the synthetic hydroxysodalite. The Si/Al molar ratio and reaction time both affect the purity of the synthetic hydroxysodalite. Optimum conditions for synthesizing hydroxysodalite using a one-step water-bath method at moderate temperature are as follows: a Na/Si molar ratio of 12, a Si/Al molar ratio of 1.0, a reaction temperature of 90 °C, and a reaction time of 12 h.


Author(s):  
Po Li ◽  
Weilan Xue ◽  
Zuoxiang Zeng ◽  
Li Sun ◽  
Yu Bai

Polyvinyl butyral (PVB) was prepared by the condensation reaction of polyvinyl alcohol (PVA) with n-butyraldehyde using a catalyst which is a kind of deep eutectic solvent (DES) made of dodecyltrimethylammonium chloride and p-toluenesulfonic acid. The raw materials and products were characterized by Fourier transform infrared spectroscopy (FT-IR). The effects of the following reaction conditions on the degree of PVB acetal, yield and agglomeration of the products were investigated: the mass ratio of n-butyraldehyde to PVA (mBA/mPVA) of 0.48-0.96, the mass ratio of catalyst to PVA (mcat/mPVA) of 0.16-0.64, the low temperature reaction temperature (5-20℃), and the low temperature reaction time (1-3h). The results showed that at mBA/mPVA =0.8, mcat/mPVA =0.32, low temperature reaction temperature of 15°C and low temperature reaction time of 2 hours, the obtained PVB was a homogeneous powder with the highest acetal degree of 73.85%.


2011 ◽  
Vol 79 ◽  
pp. 99-104
Author(s):  
Yu Liu ◽  
Qin Yu Gao ◽  
Lian Xin Liu ◽  
Guang Xia Shi

This paper studied on the industry synthesis process of anti-oxidant RD ((2,2,4- trimethyl-1,2-dihydro- quinoline polymer (C12H15N)n.n=2-4)) .The content of dimer, trimer and tetramer of RD were taken as the inspection targets, used the orthogonal design method, and take the ratios of keto-amine, the reaction time, the reaction temperatures and the ratios of catalyst acid-amine as inspect factors to optimized reaction condition. The result indicated that the best ratio of keto-amine is 6.5:1, the reaction time is 6 hours, the range of the reaction temperature is 115-120°C, the beat ratio of acid-amine is 0.2: 1 (the proportion is the concentration ratio for mole). Under the optimization conditions, the yield stability of RD.


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