Enzymatically fibrillated cellulose pulp-based monofilaments spun from water; enhancement of mechanical properties and water stability

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

ACS Applied Polymer Materials ◽

10.1021/acsapm.1c01371 ◽

2022 ◽

Author(s):

Carina Haddad ◽

E. A. Kalani D. Edirisinghe ◽

Hope M. Brown ◽

Alexis D. Ostrowski

Keyword(s):

Mechanical Properties ◽

Water Stability ◽

Vanadium Ion

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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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Microstructure and mechanical properties of gypsum composites reinforced with recycled cellulose pulp

Materials Research ◽

10.1590/s1516-14392008000400002 ◽

2008 ◽

Vol 11 (4) ◽

pp. 391-397 ◽

Cited By ~ 22

Author(s):

Magaly Araújo Carvalho ◽

Carlito Calil Júnior ◽

Holmer Savastano Junior ◽

Rejane Tubino ◽

Michele Tereza Carvalho

Keyword(s):

Mechanical Properties ◽

Cellulose Pulp ◽

Microstructure And Mechanical Properties

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Mechanical Properties of Bio-Composites Based on Epoxy Resin and Nanocellulose Fibres

Materials ◽

10.3390/ma14133576 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3576

Author(s):

Martyna Roszowska-Jarosz ◽

Joanna Masiewicz ◽

Marcin Kostrzewa ◽

Wojciech Kucharczyk ◽

Wojciech Żurowski ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Epoxy Resin ◽

Raw Materials ◽

Critical Stress Intensity Factor ◽

Epoxy Composites ◽

Chemical Extraction ◽

Cellulose Pulp ◽

The Impact ◽

Unmodified Epoxy

The aim of our research was to investigate the effect of a small nanocellulose (NC) addition on an improvement of the mechanical properties of epoxy composites. A procedure of chemical extraction from pressed lignin was used to obtain nanocellulose fibers. The presence of nanoparticles in the cellulose pulp was confirmed by FTIR/ATR spectra as well as measurement of nanocellulose particle size using a Zetasizer analyzer. Epoxy composites with NC contents from 0.5% to 1.5% w/w were prepared. The obtained composites were subjected to strength tests, such as impact strength (IS) and resistance to three-point bending with a determination of critical stress intensity factor (Kc). The impact strength of nanocellulose composites doubled in comparison to the unmodified epoxy resin (EP 0). Moreover, Kc was increased by approximately 50% and 70% for the 1.5 and 0.5% w/w NC, respectively. The maximum value of stress at break was achieved at 1% NC concentration in EP and it was 15% higher than that for unmodified epoxy resin. The highest value of destruction energy was characterized by the composition with 0.5% NC and corresponds to the increase of 102% in comparison with EP 0. Based on the analysis of the results it was noted that satisfactory improvement of the mechanical properties of the composite was achieved with a very small addition of nanofiller while other research indicates the need to add much more nanocellulose. It is also expected that this kind of use of raw materials will allow increasing the economic efficiency of the nanocomposite preparation process. Moreover, nanocomposites obtained in this way can be applied as elements of machines or as a modified epoxy matrix for sandwich composites, enabling production of the structure material with reduced weight but improved mechanical properties.

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