Mechanically Robust Hydrophobized Double Network Hydrogels for Water Purification

Water swollen polymer networks are attractive for applications ranging from tissue regeneration to water purification. For water purification, charged polymers provide excellent ion separation properties. However, many ion exchange membranes (IEMs) are brittle, necessitating the use of thick support materials that ultimately decrease throughput. To this end, a series of double network hydrogels (DNHs), synthesized with varied composition to decrease water content, are examined as robust membrane materials for water purification. One network contains fixed anionic charges, while the other comprises a copolymer with different ratios of hydrophobic ethyl acrylate (EA) and hydrophilic dimethyl acrylamide (DMA) repeat units. Characterizing water content and mechanical performance in free standing DNH films reveals a ~5× decrease in water content, while increasing ultimate stress and strain by ~3.5× and ~4.5× for 90:5 EA:DMA relative to pure DMA. Salt transport properties relevant to water purification, including permeability, solubility, and diffusivity, are measured and show improved performance upon reducing water content. Overall, the ability to simultaneously reduce water content, increase mechanical integrity, and decrease salt transport rates highlights the potential of DNHs for membrane applications.

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Polyacrylamide/Chitosan-Based Conductive Double Network Hydrogels with Outstanding Electrical and Mechanical Performance at Low Temperatures

ACS Applied Materials & Interfaces ◽

10.1021/acsami.1c08421 ◽

2021 ◽

Author(s):

Jing Cong ◽

Zhiwei Fan ◽

Shaoshan Pan ◽

Jie Tian ◽

Weizhen Lian ◽

...

Keyword(s):

Low Temperatures ◽

Mechanical Performance ◽

Double Network

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Synthesis and mechanical behavior of interpenetrating polymer networks: Poly(ethyl acrylate) and polystyrene

Journal of Polymer Science Part A-2 Polymer Physics ◽

10.1002/pol.1969.160070214 ◽

1969 ◽

Vol 7 (2) ◽

pp. 425-427 ◽

Cited By ~ 67

Author(s):

L. H. Sperling ◽

D. W. Friedman

Keyword(s):

Mechanical Behavior ◽

Polymer Networks ◽

Ethyl Acrylate ◽

Interpenetrating Polymer Networks

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Shear strength characteristics of Jerash expansive soil

Journal of Advanced Sciences and Engineering Technologies ◽

10.32441/jaset.03.02.08 ◽

2021 ◽

Vol 3 (2) ◽

pp. 74-80

Author(s):

Talal Masoud

Keyword(s):

Shear Strength ◽

Internal Friction ◽

Water Content ◽

Direct Shear Test ◽

Shear Test ◽

Expansive Soil ◽

Content Increase ◽

Direct Shear ◽

Initial Water ◽

Angle Of Internal Friction

The results of the direct shear test on Jerash expansive soil show the effect of the initial water content on the cohesion (c) and on the angel of internal friction ( ) [shear strength parameters].it show that, as the initial water increase, the cohesion (c) of Jerash expansive soil also increase up to the shrinkage limit, after that increase of water even small amount, decrease the cohesion of the soil. On the other hand, the results of direct shear test show also that as the water content increase, the angle of internal friction ( )remain unchanged up to shrinkage limit , any increase of water cause a large decrease on the angle of internal friction of Jerash expansive soil.

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Influence of Polyacrylate on the Compatibility in P(MMA/EA)/PU Semi-IPNs

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.627.873 ◽

2012 ◽

Vol 627 ◽

pp. 873-877

Author(s):

Xiao Xia Jian ◽

Le Qin Xiao ◽

Wei Liang Zhou ◽

Hai Qin Ding

Keyword(s):

Mechanical Properties ◽

Thermal Analysis ◽

Polymer Networks ◽

Thermoplastic Elastomer ◽

Ethyl Acrylate ◽

Interpenetrating Polymer Networks ◽

Structure And Properties ◽

Infrared Spectrometer ◽

Nuclear Magnetic Resonance Spectrometry ◽

Magnetic Resonance Spectrometry

The Semi-Interpenetrating Polymer Networks(Semi-IPNs) of poly(methyl methyacrylate/ethyl acrylate)(P(MMA/EA)) and polyurethane thermoplastic elastomer (PU) were synthesized by PU and copolymer of methyl methacrylate and ethyl acrylate to improve the compatibility of polymethyl methacrylate(PMMA) and PU Semi-IPNs . The structure and properties were investigated by Fourier transform infrared spectrometer, Solid nuclear magnetic resonance spectrometry, Dynamic mechanical thermal analysis and Mechanical properties. The tensile stress of (P(MMA/EA)/PU)( P(MMA/EA):PU=3:7) can get to 9.6MPa, the additional physical crosslinks and entanglement for Semi-IPNs are the reasons.

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Optimization of hammer grinder for white lupine “Dega” processing

Кормопроизводство ◽

10.25685/krm.2021.2021.2.007 ◽

2021 ◽

pp. 36-41

Author(s):

В.М. Косолапов ◽

С.И. Тютюнов ◽

А.Э. Ставцев ◽

С.В. Зверев

Keyword(s):

Water Content ◽

Protein Concentration ◽

Fine Particles ◽

Energy Costs ◽

Content Increase ◽

Grain Crushing ◽

Sieve Size ◽

White Lupine ◽

Pneumatic Separation ◽

Water Content Increase

Исследования проведены в 2019 году в лаборатории «Технология и техника мукомольно-крупяного производства» ВНИИ зерна и продуктов его переработки – филиала ФГБНУ «ФНЦ пищевых систем им. В. М. Горбатова» РАН. В качестве объекта исследований использовали зерно белого люпина сорта Дега. Эксперименты по изучению условий измельчения зерна проводились на лабораторной молотковой дробилке с регулируемой частотой вращения ротора. Рассматривалось влияние влажности зерна, скорости молотков и диаметра отверстий рабочего сита дробилки на выход крупки и содержание в ней недоруша (зёрен и частиц с остатками оболочки, крупных частей неотвеянной оболочки). Использование простой технологической схемы обрушения зерна белого люпина на базе молотковой дробилки позволило получить до 70% крупки с повышенным содержанием белка и низким содержанием клетчатки. С ростом скорости молотков и уменьшением диаметра отверстий рабочего сита дробилки выход крупки снижался, что объяснимо ростом доли мелкой фракции, которая отвеивается при пневмосепарации. Крупка представляет из себя частицы ядра с недорушем, а относы являются смесью дроблёной оболочки с мучкой — мелкой фракцией дробленого ядра. Основная доля мучки ядра была сосредоточена во фракции меньше 1,5–2,0 мм, в которой содержится больше белка. Данная фракция составляла около половины массы относов или около 15% от массы зерна. Наличие недоруша в крупке повышало содержание в ней клетчатки и снижало содержание белка. С ростом влажности и диаметра отверстий рабочего сита дробилки содержание недоруша возрастало, а при росте скорости — падало. При фиксированной влажности содержание недоруша можно снизить за счёт повышения скорости удара (увеличения числа оборотов) или уменьшения диаметра отверстий рабочего сита дробилки, но и тот и другой метод повышают энергозатраты. При возрастании скорости удара росла и производительность. The research was conducted in 2019. Hammer grinder with adjustable rotor speed was used to crush the grain of white lupine “Dega”. The effects of grain water content, crushing speed and sieve size were analyzed on grain crushing and hulling as well as the proportion of unhulled grain. This technology resulted in up to 70% of crushed hulled grain rich in protein but poor in fiber. Increase in hammer speed and decrease in sieve size negatively affected the proportion of crushed grain due to the high content of fine fractions discarded further via pneumatic separation. Crushed hulled grain is normally combined with unhulled grain. The mixture of crushed hulls and fine particles of crushed grain are to be separated. Most of the bran was found in the fraction of 1.5–2.0 mm containing more protein. This fraction amounted to 15% of grain mass and 50% of the mass to be discarded. Unhulled grain mixed with crushed hulled grain increased fiber content in the mixture but reduced protein concentration. Higher grain water content and larger sieve size increased the amount of unhulled grain, while higher hammer speed decreased its fraction. Higher hammer speed as well as smaller sieve size reduce the content of unhulled grain but increased energy costs under constant grain water content. Increase in hammer speed improved the capacity of the grinder.

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