Photoreactivity and Enhanced Mechanical Properties and Water Stability in Polysaccharide-Based Films Using Vanadium Ion Coordination

Abstract Porous polyurethane concrete (PPUC) is a novel material for permeable pavements and is considered as an alternative to porous asphalt or porous cement concrete. However, studies of the mechanical properties of PPUC are still insufficient. In this study, the comprehensive mechanical properties and water stability of PPUC with different gradations and polyurethane dosages were investigated, and its water damage mechanism was preliminarily explored. The results show that the flexural strength and Marshall stability of PPUC can more easily reach the index in the standards of porous cement concrete or porous asphalt, while the compressive strength and abrasion resistance are the weak points of its mechanical properties and need to be further optimized. The mechanical properties and water stability of PPUC were effectively improved by increasing the polyurethane dosage and using continuously graded aggregates. PPUC is more susceptible to water damage because water reacts with the residual isocyanate groups within the polyurethane film to generate carbon dioxide gas, which reduces the cohesion and adhesion performance of polyurethane film. This study provides a comprehensive understanding of the mechanical properties of PPUC and an initial insight into the mechanism of water damage.

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Some mechanical properties of aggregates of top soils from the IJsselmeer polders. 1. Undisturbed soil aggregates.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v32i3.16897 ◽

1984 ◽

Vol 32 (3) ◽

pp. 205-214

Author(s):

A.R. Dexter ◽

B. Kroesbergen ◽

H. Kuipers

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Soil Aggregates ◽

Clay Content ◽

Water Stability ◽

Undisturbed Soil

Aggregates were collected from the arable layer at eight sites in the IJsselmeer polders. The compositions of the soils were determined, and measurements were made of porosities, tensile strengths and water stabilities of undisturbed aggregates. Porosity was negatively correlated with the age of the soils since reclamation. Tensile strength of dry aggregates and water stability were both positively correlated with the clay content. The soils had extremely high values of friability. Tensile strength was negatively correlated with porosity. Porosity had no clear influence on water stability. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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The Effect of the Substitution Position of Nitrogen Atoms on Copolyimide Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1079-1080.66 ◽

2014 ◽

Vol 1079-1080 ◽

pp. 66-69

Author(s):

Yu Han Li ◽

Ri Zhe Jin

Keyword(s):

Mechanical Properties ◽

Water Uptake ◽

Water Stability ◽

Side Chains ◽

Thermally Stable ◽

Dimensional Changes ◽

Film Forming ◽

Diamine Monomer

Two containing nitrogen diamine monomer, 2-(4-aminophenyl)-5-aminopyrimidine (PAPRM) and 2,5-two(dimethyl amino methylene)-1,4-((paraamino) phenyl)benzene(DMAPB), was synthesized. The corresponding copolyimide containing 40–80 mol % PAPRM and DMAPB were prepared. The copolymers showed excellent solubility and good ﬁlm-forming capability. Most of the SPI membranes were both tough and flexible and thermally stable up to 330 °C.With increasing content of the nitrogen atoms, water uptake of membranes and dimensional changes also remarkable decrease. Compared with the main chains containing nitrogen atoms, the side chains type displayed excellent water stability and good mechanical properties.

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The influence of inorganic additive on the water stability and mechanical properties of recycled rubber, polyethylene terephthalate, high density polyethylene and wood composites

Journal of Cleaner Production ◽

10.1016/j.jclepro.2017.07.103 ◽

2017 ◽

Vol 165 ◽

pp. 630-636 ◽

Cited By ~ 11

Author(s):

Mihaela Cosnita ◽

Cristina Cazan ◽

Anca Duta

Keyword(s):

Mechanical Properties ◽

Polyethylene Terephthalate ◽

High Density Polyethylene ◽

High Density ◽

Water Stability ◽

Wood Composites ◽

Recycled Rubber

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Mechanical Properties and Water Stability of High Ductility Magnesium Phosphate Cement-Based Composites (HDMC)

Materials ◽

10.3390/ma14123169 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3169

Author(s):

Hu Feng ◽

Yang Wang ◽

Aofei Guo ◽

Xiangyu Zhao

Keyword(s):

Mechanical Properties ◽

Water Immersion ◽

Potassium Dihydrogen Phosphate ◽

Retention Rates ◽

Magnesium Phosphate ◽

Dihydrogen Phosphate ◽

Water Stability ◽

High Ductility ◽

Toughness Index ◽

Ambient Curing

In this study, the compressive test and four-point flexural test were carried out to explore the water stability as well as mechanical properties of high ductility magnesium phosphate cement-based composites (HDMC). The effects of ambient curing age (7 d and 28 d), water immersion age (7 d, 28 d, and 56 d), water/binder ratio (W/B), and magnesium oxide/potassium dihydrogen phosphate ratio (M/P) on the mechanical properties (compressive strength, first-crack strength, ultimate flexural strength, ductility index, and toughness index) and water stability of the HDMC were examined. The results showed that the 28-day ambient curing could lead to higher retention rates of strength, ductility, and toughness than 7-day ambient curing, indicating better water stability; however, it did not result in significant improvement in the mechanical properties of the HDMC. As the water immersion age increased, the mechanical properties of the HDMC with 7-day ambient curing showed an obvious downward trend; the mechanical properties of the HDMC with 28-day ambient curing did not show an obvious decrease and even could be increased in many cases, especially when the water immersion age was 56 days; and the change of water stability was consistent with that of the mechanical properties. If all indexes and their corresponding retention rates were considered comprehensively, the W/B ratio of 0.16 and the M/P ratio of 5 seemed to be the optimum values for the HDMC. The scanning electron microscopy analysis confirmed that the water immersion had a large adverse effect on the HDMC and thus reduced their mechanical properties.

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Effect of Temperature and Asphalt Binder Type on the Properties of Foamed Asphalt Mix

MATEC Web of Conferences ◽

10.1051/matecconf/201820602015 ◽

2018 ◽

Vol 206 ◽

pp. 02015

Author(s):

Martin Bitolog ◽

Mouhamed Bayane Bouraima ◽

Xiao-hua Zhang ◽

Christian Magloire Ndjegwes ◽

Yanjun Qiu

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Asphalt Mixture ◽

Indirect Tensile Strength ◽

Stability Test ◽

Effect Of Temperature ◽

Foaming Properties ◽

Water Stability ◽

Splitting Test ◽

Indirect Tensile

In this study, an effect of temperature on both indirect tensile strength (ITS) test and Marshall Stability Test of foam asphalt mixture using Shell #70 A asphalt is firstly investigated. A detailed investigation of the mechanical properties of foam asphalt mixture was then carried out using two different asphalt binders. The experimental work compares the mechanical properties of foam asphalt mixes including water stability test, indirect tensile strength (ITS) test, and freeze-thaw splitting test. The test results indicate that the foam asphalt mixture is temperature dependent and also temperature sensitive material. The foaming properties of asphalt have an important effect on the properties of the foam asphalt mixture for the strength and water stability of the foam asphalt mixture.

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