Synthesis for an Amide-Ester Type Polycarboxylate Superplasticizer and its Application in Concrete

2014 ◽  
Vol 989-994 ◽  
pp. 233-237
Author(s):  
Chong Sun ◽  
Guang Jun Zheng ◽  
Yao Bi ◽  
Hui Zhou
Keyword(s):  
Molecular Weight ◽  
Reaction Time ◽  
Cement Mortar ◽  
Concrete Strength ◽  
Gel Permeation Chromatography ◽  
Step Method ◽  
Application Performance ◽  
Polycarboxylate Superplasticizer ◽  
Gel Permeation ◽  
New Type

A new type of amide-modified polycarboxylate superplasticizer was synthesized by a two-step method: Firstly, a mixture of amidated and esterified products reacted by maleic anhydride and 2-aminoethanol was modified through Mannich reaction. Then, the modified product was reacted with Prenyl alcohol polyethenoxy ether (TPEG), acrylic acid and other monomers to obtain an amide-structured polycarboxylate superplasticizer. The molecular weight and molecular weight distribution were measured by Gel permeation chromatography (GPC). Lastly, the optimum AA to modified product ratio, initiator dosage and reaction time were determined by cement mortar test. The concrete application performance showed that the synthesized superplasticizer could improve the fluidity of the concrete and maintain the slump loss as well. The introduction of modified PCE has no harm for the concrete strength.

Molecular Weight and its Distribution of PET Depolymerization Residue under Microwave Irradiation

2014 ◽  
Vol 997 ◽  
pp. 371-374
Author(s):  
Cheng Cai Zeng ◽  
Qing Hua Tang ◽  
Ling Zhong ◽  
Zhi De Liu ◽  
Dong Zhang
Keyword(s):  
Molecular Weight ◽  
Reaction Time ◽  
Microwave Irradiation ◽  
Gel Permeation Chromatography ◽  
Molecular Chain ◽  
Gel Permeation

The molecular chain of PET would be broken in the process of depolymerization reactions under microwave irradiation, which would lead to changes in molecular weight. In this paper, the molecular weight of PET residue measured by gel permeation chromatography (GPC) was used to track the progress of PET depolymerization. The results showed that the molecular weight of the residue after depolymerization under 180°Cdecreases as reaction time increases, however when the temperature of depolymerization was 190°Cor 200°C, with the reaction time increases, the molecular weight of residue decreased first and then increased slightly.

Study on Structure and Tanning Properties of Copolymer of Resorcinol and 3,5-Dihydroxyl Benzoic Acid

2012 ◽  
Vol 487 ◽  
pp. 48-52
Author(s):  
Sheng Hua Lv ◽  
Gong Rui ◽  
Di Li
Keyword(s):  
Molecular Weight ◽  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Gel Permeation Chromatography ◽  
Radical Copolymerization ◽  
Mass Ratio ◽  
Monomer Composition ◽  
Chrome Tanning ◽  
Gel Permeation

The radical copolymerization of resorcinol (RSC) and 3,5-dihydroxyl benzoic (DHBA) was carried out in water by the initiator of horseradish (HRP)/H2O2. It was discussed that the effects of monomer composition on the properties of the copolymer. The best monomer mass ratio of RSC:DHBA was 60:40 and the shrink temperature can reached to 88.5oC. The tanning result indicated that the copolymer of RSC and DHPA has particularly excellent tanning properties and can be served as leather tannage substitute for chrome tanning materials. And also the mechanism of the HRP initiated copolymerization was proposed. The structure and molecular weight of the copolymer was characterized by Fourier Transform Infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) and Gel Permeation Chromatography (GPC). The copolymer can be as tannage and retannage in making leather process. The results showed that it has excellent tanning properties and retanning effects.

scholarly journals Correlations between retention volume and molecular size parameters in gel permeation chromatography of small molecules

1975 ◽  
Vol 28 (1) ◽  
pp. 189 ◽  
Author(s):  
RA Shanks
Keyword(s):  
Molecular Weight ◽  
Small Molecules ◽  
Organic Molecules ◽  
Retention Volume ◽  
Molecular Size ◽  
Gel Permeation Chromatography ◽  
Molar Volumes ◽  
Small Organic Molecules ◽  
Molecular Dimension ◽  
Gel Permeation

Gel permeation columns of Bio Beads S-X8 have been used to provide separation of oligomers and other small organic molecules. Results show successful separations up to molecular weight c. 600. The retention times of compounds have been correlated with the largest molecular dimension of the molecules and also with molar volumes.

Alternative Tanning Agent for Leather Industry from a Sustainable Source

2021 ◽  
Vol 116 (3) ◽  
Author(s):  
Cigdem Kilicarislan Ozkan ◽  
Hasan Ozgunay
Keyword(s):  
Molecular Weight ◽  
Corn Starch ◽  
Periodate Oxidation ◽  
Gel Permeation Chromatography ◽  
Proton Nuclear Magnetic Resonance ◽  
Resonance Spectroscopy ◽  
Leather Industry ◽  
Sodium Metaperiodate ◽  
Gel Permeation ◽  
Aldehyde Content

Dialdehyde starches with different aldehyde content from native corn starch were prepared by sodium periodate oxidation to be used as a tanning agent in leather making. For this purpose, native corn starch was oxidized with sodium metaperiodate in different molar ratios. After oxidation processes, the yields, solubility in water and aldehyde contents of the obtained dialdehyde starches were determined as well as structure characterizations by Proton Nuclear Magnetic Resonance Spectroscopy, Fourier Transform Infrared Spectroscopy and Gel Permeation Chromatography. Evaluating the gel permeation chromatography data, the dialdehyde starch samples which were thought to be in appropriate molecular weight/size to penetrate into skin fibers were selected to be used in the tanning process. Their tanning abilities were evaluated by investigating hydrothermal stabilities, filling and fiber isolation characteristics and physical properties determined by mechanical tests and organoleptically. From the evaluation of the results, it was revealed that sodium metaperiodate oxidized starches which have appropriate molecular weight and adequate aldehyde content has a remarkable tanning effect and can be utilized as a tanning agent with the advantages of not necessitating pickling process which means saving time and simplifying the production but more importantly offering an important advantage from an environmental point of view.

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