The Radiation Curing of Elastomers. I. Physical Strength

Abstract Data has been presented which shows that sulfur crosslinks have very little importance in producing maximum tensile strength in amorphous polymers. The results suggest that the distribution of crosslinks, especially in the case of crystalline polymers, is. a factor to be considered. In general, radiation cured elastomer compounds have physical strength properties very similar to sulfur or peroxide cured compounds. This similarity has been noted for a wide number of other elastomers not reported here. The observed strength deficiency is minor in degree and of little industrial importance provided the other properties are not too different. These properties such as fatigue life, abrasion resistance, and hysteresis will be discussed in a later publication.

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Effect of the Changes in Bulk Density and Granulometric Properties on the Strength Properties of the Moulding Sand Mixtures

International Journal of Engineering and Management Sciences ◽

10.21791/ijems.2020.2.15. ◽

2020 ◽

Vol 5 (2) ◽

pp. 116-122

Author(s):

Henrietta Hudák ◽

László Varga

Keyword(s):

Particle Size ◽

Tensile Strength ◽

Compressive Strength ◽

Particle Size Distribution ◽

Mineralogical Composition ◽

Strength Properties ◽

The Other ◽

Comparative Measurement ◽

Sand Surface ◽

Main Components

Foundry technology uses a lot of several natural materials. Sands use for preparing mixtures whereby making moulds or cores. Sand is defined as a granular, refractory major portion of mixture (90 – 98% in dependence on used binder). Sand properties depend on it has chemical and mineralogical composition; mainly particle size distribution and shape of grains and its size and sand surface texture. A comparative measurement of two quartz sand with different surface quality was carried out. Greensand mixtures were prepared to measure their permeability, compressive strength and wet tensile strength. The strength of sand mixtures has two main components. One of them is the cohesion of the binder; the other one is the adhesion between the binder and the foundry sand. The aim of this research is to determine the ratio of cohesion and adhesion within the strength values.

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Impact of Laser Intensities at Various DPI and Pixel Time on the Properties of Denim Garments

Journal of Advanced Research in Materials Science ◽

10.37934/arms.77.1.113 ◽

2021 ◽

Vol 77 (1) ◽

pp. 1-13

Author(s):

Md. Shamsuzzaman ◽

Ziad Abdul Awal ◽

Dip Das

Keyword(s):

Tensile Strength ◽

Outer Surface ◽

Abrasion Resistance ◽

The Other ◽

Added Value ◽

Laser Exposure ◽

Fabric Weight ◽

Time Required ◽

Fabric Surface ◽

Tear Resistance

This paper investigates the changes in the properties of denim garments with respect to laser intensities of different DPI and Pixel Time. The laser added value to denim garments can fade the outer surface and the yarn portion significantly. In this research, DPI 20 and 25 along with Pixel Time 100, 150 and 200 were applied on samples to investigate the fabric weight, absorbency, crease recovery, tear resistance, tensile strength, pilling and abrasion resistance. For each of the cases, increased DPI and Pixel Time had much greater impact than other parameters on the denim garment samples. After treatment, the fabric sample indicated around 10-30% in weight reduction. The absorbency property of the sample on the other hand showed that higher DPI and Pixel Time required less time to absorb the water on the fabric surface. Furthermore, fabric crease recovery property reduced sharply where maximum 33% crease could not recover after laser exposure. For both tear resistance and tensile strength, especially warp way direction, property reduced more compared to weft way direction due to higher fading effects. After 12,000 cycles, both pilling and abrasion resistance property demonstrated significant reduction for higher laser intensities.

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The Relation Tensile Strength And Flexibility Of Bamboo For Soil Stabilization

Journal of Advanced Civil and Environmental Engineering ◽

10.30659/jacee.4.1.11-19 ◽

2021 ◽

Vol 4 (1) ◽

pp. 11

Author(s):

Khoiriya Latifah ◽

Joko Siswanto ◽

Bambang Supriyadi ◽

Carsoni C

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Soil Stabilization ◽

Strength Properties ◽

High Compressive Strength ◽

Maximum Tensile Strength ◽

The World ◽

Bamboo Fibers ◽

The Relationship

Bamboo is an abundant material and easily available in Indonesia. In addition to having high compressive strength and tensile strength as well as ease of obtaining and low prices, bamboo is a consideration and focus in developing in the world of construction today. In this study, bamboo is used for soil stabilization, where bamboo is used in the form of fibre. This research focuses on the strength properties of various types of bamboo. The focus is to investigate the relationship between the maximum tensile strength of bamboo and the flexibility of bamboo in soil stabilization. This is very important, because bamboo fibers used for soil stabilization rely on their tensile strength rather than their compressive strength. Thus, the optimum tensile strength and flexibility of bamboo must be of particular concern. From the results of the study of the tensile strength of two types of bamboo, namely Apus Bamboo and Java Bamboo, the Apus Bamboo results were found to have a higher tensile strength of 225.57 mpa with maximum flexibility of 19.99 mm and 43.76 mpa for tensile strength of Javanese Bamboo with a level of flexibility of 10.26 mm.

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A Proposition for the Estimation of the Maximum Tensile Strength of Variously Charged Nanocellulosic Film Materials Provided by Vacuum Filtration

Nanomaterials ◽

10.3390/nano11020543 ◽

2021 ◽

Vol 11 (2) ◽

pp. 543

Author(s):

Tom Lindström

Keyword(s):

Tensile Strength ◽

Strength Properties ◽

Vacuum Filtration ◽

Suggested Procedure ◽

Maximum Tensile Strength ◽

Research Activities ◽

Experimental Laboratory ◽

Two Measures ◽

The Impact

This short investigation deals with a review of the tensile strength properties of six different types of nanocellulose films (carboxymethylated, carboxymethylcellulose-grafted, enzymatically pretreated, phosphorylated, sulfoethylated, and alkoxylated nanocellulose films) manufactured using identical protocols and the determination of the apparent nanocellulose yield of the same nanocelluloses and their tensile strength properties at different extents of delamination (microfluidization). The purpose was to test a previously suggested procedure to estimate the maximum tensile strength on these different procedures. A second goal was to investigate the impact of the nanocellulose yield on the tensile strength properties. The investigations were limited to the nanocellulose research activities at RISE in Stockholm, because these investigations were made with identical experimental laboratory protocols. The importance of such protocols is also stressed. This review shows that the suggested procedure to estimate the maximum tensile strength is a viable proposition, albeit not scientifically proven. Secondly, there is a relationship between the nanocellulose yield and tensile strength properties, although there may not be a linear relationship between the two measures.

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Blends of Elastomers and Thermoplastics—A Review

Rubber Chemistry and Technology ◽

10.5254/1.3534998 ◽

1976 ◽

Vol 49 (4) ◽

pp. 978-991 ◽

Cited By ~ 20

Author(s):

J. R. Dunn

Keyword(s):

Tensile Strength ◽

Physical Properties ◽

Environmental Stress ◽

Abrasion Resistance ◽

Impact Resistance ◽

The Other ◽

Tear Strength ◽

Stress Cracking ◽

Environmental Stress Cracking ◽

Thermoplastic Blends

Abstract In blends of elastomers and thermoplastics one component may be regarded as reinforcing the other. Examples are enhancement of tensile strength, tear strength, abrasion resistance, and modulus of elastomers by thermoplastics and improvement of impact resistance and environmental stress-cracking resistance of thermoplastics by elastomers. Certain elastomer-thermoplastic blends are rapidly growing in importance as thermoplastic rubbers because they combine the processing characteristics of plastics with physical properties similar to those of vulcanized elastomers.

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Effect of Sulfur during Radiation Curing of Poly(Vinyl Ethyl Ether) and Ethylene-Propylene Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3539542 ◽

1963 ◽

Vol 36 (1) ◽

pp. 248-258 ◽

Cited By ~ 5

Author(s):

Joginder Lal ◽

James E. McGrath

Keyword(s):

Tensile Strength ◽

Ethyl Ether ◽

Triphenyl Phosphine ◽

Radiation Curing ◽

Elongation At Break ◽

Ethylene Propylene ◽

Maximum Tensile Strength ◽

Lower Radiation Dose ◽

Ethylene Propylene Rubber ◽

Sulfur Containing

Abstract A study was made of the effect of sulfur, during radiation curing, on the physical properties of poly(vinyl ethyl ether) and an ethylene/propylene copolymer containing HAF carbon black. The presence of sulfur enabled the attainment of higher maximum tensile strength and generally higher crosslink density than when sulfur was omitted. Furthermore, the maximum tensile strength of the sulfur-containing samples was obtained at a lower radiation dose than in the corresponding control experiments. For a given swelling ratio, a higher tensile strength was generally obtained for samples irradiated in the presence of sulfur. For a given dose of radiation, the per cent elongation-at-break values of poly(vinyl ethyl ether) samples decreased as the amount of sulfur in the recipe was increased. In contrast, in the ethylene/propylene rubber the presence of sulfur resulted in an increase in the elongation values. The per cent sol values were also quite high for the ethylene/propylene vulcanizates as compared to the corresponding values in poly(vinyl ethyl ether) samples. In both rubbers, lower sol values were obtained in the presence of sulfur. Chemically bound sulfur was found in poly(vinyl ethyl ether) samples irradiated in the presence of elemental sulfur or dicyclopentamethylene thiuram tetrasulfide. The ability of the network to lose a portion of the combined sulfur by reaction with triphenyl phosphine may indicate that some of the crosslinks contain disulfide and/or polysulfide groups.

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Chemical, anatomical, and technology aspects of Eucalyptus benthamii and Eucalyptus dunii for use in an integrated pulp and paper mill

TAPPI Journal ◽

10.32964/tj14.2.73 ◽

2015 ◽

Vol 14 (2) ◽

pp. 73-81 ◽

Cited By ~ 5

Author(s):

GISELY SAMISTRARO ◽

PETER W. HART ◽

JORGE LUIZ COLODETTE ◽

RICARDO PAIM

Keyword(s):

Energy Levels ◽

Black Liquor ◽

Basic Density ◽

Paper Mill ◽

Frost Tolerance ◽

Strength Properties ◽

Kappa Number ◽

Pulp Yield ◽

Chemical Compositions ◽

Physical Strength

Eucalyptus dunii has been commercially used in southern Brazil because of its relatively good frost tolerance and adequate productivity in the winter months. More recently, interest has grown in cultivating Eucalyptus benthamii Maiden & Cambage, which presents even superior frost tolerance compared to E. dunii and is highly productive as well. The quality of E. benthamii for pulp production is not yet proven. Thus, the chemical, anatomical, and technological aspects of pulp made from E. benthamii were compared with those of E. dunii for unbleached paper production. Samples of E. benthamii chips were obtained and analyzed for their basic density, chemical composition, higher heating value, trace elemental analysis, and chip size distribution. The chips were kraft cooked using conditions that produced a 74 ± 6 kappa number. The pulps were characterized for kappa number, yield, viscosity, and morphologic characteristics (e.g., length, wall thickness, and coarseness). Black liquor was analyzed for total solids, organics, inorganics, sodium sulfide, sodium hydroxide, and sodium carbonate. Brownstocks were beaten at five different energy levels in a Valley beater, and the physical strength properties of 120 g/m² handsheets were measured to develop a beater curve. The results of this study showed differences in delignification between the two woods and lower pulp yield for E. benthamii , which are related to their chemical compositions and basic densities. The E. benthamii studied in this work exhibited higher amounts of lignin and extractives, lower carbohydrate content, and lower basic density. However, cooking a blend of the two woods afforded good results in pulping and in physical pulp properties.

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Does kraft hardwood and softwood pulp viscosity correlate to paper properties?

TAPPI Journal ◽

10.32964/tj15.10.643 ◽

2016 ◽

Vol 15 (10) ◽

pp. 643-651 ◽

Cited By ~ 1

Author(s):

ROBERT J. OGLESBY ◽

HUMPHREY J. MOYNIHAN ◽

RICARDO B. SANTOS ◽

ASHOK GHOSH ◽

PETER W. HART

Keyword(s):

Physical Properties ◽

Strength Loss ◽

Strength Properties ◽

Clear Correlation ◽

Paper Properties ◽

Physical Strength ◽

Pulp Viscosity ◽

Softwood Pulp ◽

The Impact ◽

Increased dryness after pressing and wet web strength by utilizing foam application technology

TAPPI Journal ◽

10.32964/tj15.11.731 ◽

2016 ◽

Vol 15 (11) ◽

pp. 731-738 ◽

Cited By ~ 1

Author(s):

KARITA KINNUNEN-RAUDASKOSKI ◽

KRISTIAN SALMINEN ◽

JANI LEHMONEN ◽

TUOMO HJELT

Keyword(s):

Tensile Strength ◽

Guar Gum ◽

Paper Industry ◽

Reference Sample ◽

Strength Properties ◽

Cellulose Microfibrils ◽

Application Technology ◽

Ethylene Vinyl Alcohol ◽

Wet Pressing ◽

Web Strength

Production cost savings by lowering basis weight has been a trend in papermaking. The strategy has been to decrease the amount of softwood kraft pulp and increase use of fillers and recycled fibers. These changes have a tendency to lower strength properties of both the wet and dry web. To compensate for the strength loss in the paper, a greater quantity of strength additives is often required, either dosed at the wet end or applied to the wet web by spray. In this pilot-scale study, it was shown how strength additives can be effectively applied with foam-based application technology. The technology can simultaneously increase dryness after wet pressing and enhance dry and wet web strength properties. Foam application of polyvinyl alcohol (PVA), ethylene vinyl alcohol (EVOH), carboxymethyl cellulose (CMC), guar gum, starch, and cellulose microfibrils (CMF) increased web dryness after wet pressing up to 5.2%-units compared to the reference sample. The enhanced dewatering with starch, guar gum, and CMF was detected with a bulk increase. Additionally, a significant increase in z-directional tensile strength of dry web and and in-plane tensile strength properties of wet web was obtained. Based on the results, foam application technology can be a very useful technology for several applications in the paper industry.

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