Water Resistance Research of Anionic Polymerized PA6/ABS Alloy

Macromolecule modification activator was prepared using prepolymer of HTBN end capped by HDI biuret (N-75). Then the ABS/PA6 co-blend polymer was prepared by anionic polymerization with putting ABS resin into molten caprolactam monomer at the temperature of 160°C~180°C and the sodium hydroxide being used as activator. In the system of in-situ synthetic ABS modified nylon resin ,when the content of ABS is at 10% with rubber modifier as compatiblizing agent for ABS and nylon, the impact strength of matrices stepped up obviously, and the effect is better than that in the system of rubber modification. Along with added ABS, the tensile strength and bending strength fell that is lower than the tensile strength of pure nylon but apparently higher than that of the rubber modification system. The increase usage of compatiblizing agent improved the intensity and rupture elongation of matrices. It was indicated that ABS obstructed spherulitic growth and resulted in the reduction of nylon crystallinity.

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Enhancing the mechanical and water resistance performances of bamboo particle reinforced polypropylene composite through cell separation

Holzforschung ◽

10.1515/hf-2019-0289 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Dan Ren ◽

Xuexia Zhang ◽

Zixuan Yu ◽

Hankun Wang ◽

Yan Yu

Keyword(s):

Water Absorption ◽

Cell Separation ◽

Water Resistance ◽

Dynamic Mechanical Properties ◽

Simple Method ◽

Interface Modification ◽

Wood Particles ◽

Bamboo Fibers ◽

Pp Composites ◽

Mechanical Performances

AbstractIt is frequently observed that bamboo particle composites (BPCs) do not show higher mechanical performances than the corresponding wood particles composites (WPCs), although bulk bamboo is much stronger than wood in mechanical performances. Herein this phenomenon was demonstrated from the cell compositions in the applied bamboo particles. To address that, a simple method to physically separate bamboo fibers (BFs) and bamboo parenchyma cells (BPs) from a bamboo particle mixture was developed. Polypropylene (PP) composites with pure BFs, BPs, a mixture of BFs and BPs (BFs + BPs), wood particles (WPs) as fillers were prepared. The flexural and dynamic mechanical properties, water absorption, and thermal properties were determined. The BF/PP composites showed the best mechanical performances (MOR at 35 MPa, MOE at 2.4 GPa), followed by WP/PP, (BF + BP)/PP, and BP/PP. They also exhibited the lowest water absorption and thickness swelling. Little difference was found for the thermal decomposition properties. However, a lower activation energy of BF/PP compared with BP/PP implied an uneven dispersion of BFs and weaker interfacial interaction between BF and PP. The results suggest that the mechanical performances and water resistance of bamboo particle/polymer composites can be significantly improved through cell separation. However, interface modification should be applied if higher performances of BF/PP composites are required.

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Water Resistance and Creep Behavior of Heat-Treated Moso Bamboo Determined by the Stepped Isostress Method

Polymers ◽

10.3390/polym13081264 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1264

Author(s):

Teng-Chun Yang ◽

Tung-Lin Wu ◽

Chin-Hao Yeh

Keyword(s):

Heat Treatment ◽

Water Absorption ◽

Creep Behavior ◽

Heat Treatment Temperature ◽

Water Resistance ◽

Absorption Efficiency ◽

Treatment Temperature ◽

Moso Bamboo ◽

Phyllostachys Pubescens ◽

Heat Treated

The influence of heat treatment on the physico-mechanical properties, water resistance, and creep behavior of moso bamboo (Phyllostachys pubescens) was determined in this study. The results revealed that the density, moisture content, and flexural properties showed negative relationships with the heat treatment temperature, while an improvement in the dimensional stability (anti-swelling efficiency and anti-water absorption efficiency) of heat-treated samples was observed during water absorption tests. Additionally, the creep master curves of the untreated and heat-treated samples were successfully constructed using the stepped isostress method (SSM) at a series of elevated stresses. Furthermore, the SSM-predicted creep compliance curves fit well with the 90-day full-scale experimental data. When the heat treatment temperature increased to 180 °C, the degradation ratio of the creep resistance (rd) significantly increased over all periods. However, the rd of the tested bamboo decreased as the heat treatment temperature increased up to 220 °C.

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Investigation Techniques of In Situ AlMg/AlN Metal Matrix Composites via Reactive Gas Injection

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.837.283 ◽

2013 ◽

Vol 837 ◽

pp. 283-289 ◽

Cited By ~ 3

Author(s):

Raluca Maria Florea ◽

Oana Bălţătescu ◽

Aurelian Buzăianu ◽

Ioan Carcea

Keyword(s):

Metal Matrix ◽

Gas Flow ◽

Sem Analysis ◽

Critical Parameters ◽

Matrix Composites ◽

Uniform Dispersion ◽

Liquid Systems ◽

Spontaneous Infiltration ◽

Reactive Gas

In this paper characteristics of an AlMg/AlN composite produced in-situ and processed in a flowing N2 atmosphere is investigated. Some critical parameters such as the manufacturing process temperature, the percentage of the magnesium consumed, the flowing reactive gas flow and the time for completing the manufacturing are considered as variables for the parametric investigation. Moreover, the effect of different amount of Mg employed has been also investigated, since Mg acts as a catalyst at the surface both for the gas/liquid and solid/liquid systems. Traditional methods were used for the basic characterization of the composite. The microstructure of the composite was investigated by optical and scanning electron microscopy (OM, SEM). SEM analysis was performed in order to observe the microstructural evolution as a function of the Mg content and to identify some reasons of the presence of porosity or any irregularities within the metal matrix. The evolution of mechanical properties, in terms of microhardness, at different percentage of Mg were monitored. By EDS technique the distribution of the elements was obtained. Furthermore, employing an optimization process, uniform dispersion of the strengthening (AlN) particles in the metal matrix with homogeneous properties along the composite material is obtained. Based on the aforementioned statements, it can be concluded that the reactions between Al, Mg and the N2 atmosphere induce spontaneous infiltration in the metal matrix. The complete mix of properties and experimentally assessed parameters can be used for industrial purpose manufacturing design and development.

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Super Absorbent polymers and their Composites for Application in Agriculture

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.38048 ◽

2021 ◽

Vol 9 (9) ◽

pp. 665-672

Author(s):

Aryan Dwivedi

Keyword(s):

Mechanical Property ◽

Water Absorption ◽

Soil Water ◽

Water Retention ◽

Hydraulic Parameters ◽

Dryland Agriculture ◽

Superabsorbent Polymers ◽

Over Time

Abstract: In dryland agriculture, Superabsorbent Polymers (SAPs) are popular. However, the mechanical property, repetitive soil water absorption and release, regularly affects the water retention and hydraulic parameters of the soil, and since this property decreases progressively over time, the results of the property appear to be unpredictable. Polymers use to in agriculture field.

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INFLUENCE OF STRUCTURE OF POLYMERIC MATRIX ON STRUCTURE AND PROPERTY PRIMING COVERINGS

Proceedings of VIAM ◽

10.18577/2307-6046-2021-0-8-50-58 ◽

2021 ◽

pp. 50-58

Author(s):

V.A. Kuznetsova ◽

◽

V.G. Zheleznyak ◽

S.L. Lonskii ◽

N.A. Kovrizhkina ◽

...

Keyword(s):

Water Absorption ◽

Epoxy Resin ◽

Phase Structure ◽

Water Resistance ◽

High Water ◽

Physicomechanical Properties ◽

Structure And Property ◽

Organic Silicon ◽

To Receive ◽

Kinetics Of

Adhesion, physicomechanical properties, and also kinetics of water absorption of priming coatings on basis the E-41 epoxy resin modified by liquid Thiokol 1 and by Laproxide AF, and also their phase structure are investigated. As hardeners of primer compositions organic silicon ammine ASOT-2 and low-molecular polyamide PO-200 has been used. It is shown that use of the reactive modifier Laproxide AF and hardener ASOT-2 in the epoxy and thiokol film-formers allows to receive priming coating with uniform finely divided phase structure with low porosity and high water resistance.

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Effect of Mono- and Bilayer Coating of Nanofibrillated Cellulose, its Modification, and Shellac on Properties of Molded Pulps

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.889.79 ◽

2021 ◽

Vol 889 ◽

pp. 79-84

Author(s):

Supattra Klayya ◽

Thawan Chotimarnon ◽

Nattaya Tawichai ◽

Uraiwan Intatha ◽

Nattakan Soykeabkaew

Keyword(s):

Water Absorption ◽

Water Resistance ◽

Nanofibrillated Cellulose ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Coated Sample ◽

Uncoated Sample ◽

Bilayer Coating ◽

Layer Coating

A molded pulp is increasingly used as eco-packaging, but it has poor water resistance. Therefore, surface coating is common to perform on pulp or paper packaging to overcome this shortcoming. In this study, the bagasse (BG) molded pulp sheets were mono-and bilayer coated with nanofibrillated cellulose (NFC), modified NFC (mNFC), and shellac (S) by using a spin coating technique. Surface morphology, surface wettability, water absorption, and mechanical properties of the coated sheet samples were evaluated and compared to the uncoated sample. It was found that mNFC could effectively provide an even and complete coverage coating layer on the BG-based sheet (BG/mNFC), thanks to the partially substituted ester groups. On the contrary, NFC could not be coated evenly on the BG-based sheet surface (BG/NFC) due to its tendency towards agglomeration. The homogeneity of surface obtained from the first layer coating by NFC or mNFC affected the surface quality of the second layer coating by shellac. As a result, the BG/mNFC/S bilayer coated sample showed the smoothest surface and also the highest water resistance confirmed by SEM, contact angle measurement, and water absorption results. Furthermore, the tensile properties of both bilayer coated samples (BG/NFC/S and BG/mNFC/S) were significantly improved (p<0.05) as compared to the uncoated BG sample. This results suggested that the current bilayer coating system is very promising for advancing the performance of molded pulps in novel packaging uses.

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The Effect of Curing Time on the Properties of Fly Ash-Based Geopolymer Bricks

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.626.937 ◽

2012 ◽

Vol 626 ◽

pp. 937-941 ◽

Cited By ~ 12

Author(s):

W.I. Wan Mastura ◽

H. Kamarudin ◽

I. Khairul Nizar ◽

Mohd Mustafa Al Bakri Abdullah ◽

H. Mohammed

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Water Absorption ◽

Sodium Hydroxide ◽

Sodium Silicate ◽

Experimental Work ◽

Base Material ◽

Curing Time ◽

Curing Conditions ◽

Alkaline Activator

This paper reports the results of an experimental work conducted to investigate the effect of curing conditions on the properties of fly ash-based geopolymer bricks prepared by using fly ash as base material and combination of sodium hydroxide and sodium silicate as alkaline activator. The experiments were conducted by varying the curing time in the range of 1-24 hours respectively. The specimens cured for a period of 24 hours have presented the highest compressive strength for all ratio of fly ash to sand. For increasing curing time improve compressive strength and decreasing water absorption.

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Mechanical and water absorption properties of poly(vinyl alcohol)/sago pith waste biocomposites

Journal of Composite Materials ◽

10.1177/0021998310380287 ◽

2011 ◽

Vol 45 (11) ◽

pp. 1201-1207 ◽

Cited By ~ 9

Author(s):

Toh Wen Yee ◽

Lai Jau Choy ◽

Wan Aizan Wan Abdul Rahman

Keyword(s):

Water Absorption ◽

Vinyl Alcohol ◽

Interfacial Adhesion ◽

Water Resistance ◽

Poly Vinyl Alcohol ◽

General Phenomenon ◽

Absorption Properties ◽

Study Variable ◽

Sago Pith Waste ◽

Restricted Mobility

A series of blends of sago pith waste (SPW) and poly(vinyl alcohol) (PVA) were prepared. Mechanical and water absorption properties of the composites have been investigated. In this study, variable amounts of plasticized SPW (pSPW) and PVA (pPVA) were processed in the presence of glycerol as plasticizers. Composites were compression molded and evaluated. The addition of pSPW reduced the tensile properties of the composites, lowering the elongation and increasing Young’s modulus. The reduction in mechanical strength with the addition of pSPW was a general phenomenon due to the poor interfacial adhesion between the pPVA and Pspw, which can be proved by the scanning electron microscope observations. The percentage of water absorbed of the pPVA/pSPW biocomposites was higher than either the pPVA or pSPW alone while pSPW showed better water resistance compared to pPVA because of the restricted mobility exerted by the cellulose fibers. The incorporation of SPW into PVA decreased both the mechanical and water absorption properties.

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Water Resistance of Neoprene

Rubber Chemistry and Technology ◽

10.5254/1.3546370 ◽

1938 ◽

Vol 11 (2) ◽

pp. 383-393

Author(s):

Howard W. Starkweather ◽

Herbert W. Walker

Keyword(s):

Zinc Oxide ◽

Natural Rubber ◽

Water Absorption ◽

Chemical Reaction ◽

Water Resistance ◽

Water Soluble ◽

Significant Change

Abstract Superior water resistance of well-cured Neoprene, like that of natural rubber, depends upon the absence of water-soluble ingredients and agents that are capable of absorbing water. It has been shown that the water resistance of Neoprene varies greatly with different activating agents. This paper includes a more detailed study of the water absorption of Neoprene—magnesia—zinc oxide compounds and describes certain loaded stocks with improved water resistance. The water absorption was determined by the method already outlined, using slabs 0.20 cm. thick. Calculation of Water Absorption The water absorption can be calculated from the increase in weight or from the increase in volume of a stock during immersion in water. A difference between these values is an indication of chemically combined water. This is based upon the assumption that water undergoes no significant change in volume during absorption but that there is a change in volume during a chemical reaction. The two methods of calculating the absorption of water are shown by the equations:

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