Tensile Breaking Strength Research Articles

Tensile Property Test Analysis of Double Protein Modified Fiber

In order to study the tensile mechanical properties of the double protein modified fiber. Tensile breaking property and stress relaxation were analyzed and proper mechanical models were selected for fitting. The analysis shows that: in dry and wet, the straight tensile breaking tenacity of the double protein modified fiber is weaker than that of the modified soybean protein fiber, the elongation at break and initial modulus are near to those of the modified soybean protein fiber, the breaking tenacity of the double protein modified fiber increases slightly when wet while the elongation at break and initial modulus decline a little. In knotted and looped, the double protein modified fiber’s tensile breaking tenacity is weaker than that of the modified soybean protein and its tensile breaking strength and elongation at break decrease differently. The fitting reveals that the four element nonlinear viscoelastic model is the best to describe straight tensile. The two optimal models for knotted and looped tensile are the four element nonlinear viscoelastic model and the Improved Zurek model. In addition, the six element viscoelastic plasticity model is appropriate to simulate stress relaxation.

Influence of Construction of Textile Material on Performance of Warp Sizing

Warp sizing is the precondition of weaving for most textile material. A key fact discussed in this paper is capillary effect, by means of a series of experiments known as observation of suction lift of various types of yarn under non-wetting and wetting condition, a longitudinal and cross section of warp under microscope, tensile breaking strength of sized warp compared between non-wetting sized warp and pre-wetting sized warp, desizing time, etc, it is concluded that the capillary effect is affected by textile material construction such as linear density of warp, spinning process, yarn twist, absorbency .etc, is inherent driving force for size glue penetrating into warp so as to make weaving possible, pre-wetting process will be greatly helpful for penetrating in warp slashing, resulted from capillary effect being enhanced

Evaluation of the use of fibrin and microcrystalline chitosan membranes as carriers for transforming growth factor beta‐1

AbstractThe aim of this study was to describe the mechanical features of homogeneous and layered chitosan (Ch) and fibrin–chitosan (Fb–Ch) membranes as well the kinetics of transforming growth factor beta‐1 (TGF‐β1) release from five types of polymer carriers. Composites in the form of a film containing physiologically clotted fibrin (Fb) and microcrystalline chitosan (MCCh) were prepared and then crosslinked with calcium chloride. The films were characterized by Infrared (IR) spectroscopy, mechanical tests (film thickness, maximal tensile force, breaking strength, and elongation at break), and SEM images. The results reveal that Ch film demonstrates higher efficiency in binding TGF‐β1 and, at the same time, is less effective in its release—1.25% of the total amount between 6 h and 14 days. However, the Fb membrane binds TGF‐β1 not as strongly, which leads to more effective release of the compound—25% after 6 h and 28.98% of the total amount after 14 days. The factor TGF‐β1 is released in vitro from Fb–Ch membranes with different kinetics. The most efficient release of TGF‐β1 was observed in the case of the layered Fb–Ch (M4 L) membrane (after 14 days it reached a maximal value of 14.08% of the total amount). The release was lower with increasing Ch concentrations in the film, suggesting a high affinity of TGF‐β1 with the Fb–Ch component. The Fb–Ch membrane with incorporated TGF‐β1 may prove to be a very useful scaffold in the tissue regeneration process. This study demonstrates that Fb and MCCh gels could be used as carrier matrices for the controlled release of bioactive TGF‐β1. It was found that the degree of TGF‐β1 release from the membrane is influenced by the physiochemical and mechanical characteristics of the films and by its affinity to growth factor TGF‐β1. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Aggregation structure development and mechanical properties of biodegradable poly(butylene succinate‐co‐terephthalate) fibers

AbstractBiodegradable poly(butylene succinate‐co‐terephthalate)(PBST) copolyester, with 70 mol % butylene terephthalate (BT), was melt‐spun into fibers at various take‐up velocities ranging from 2.0 to 4.0 km/min. The structure development and mechanical properties of the as‐spun PBST fibers were intensively investigated via birefringence, wide angle X‐ray diffraction (WAXD) measurement, tensile test, and cyclic stretch test. With increasing the take‐up velocity, the initial tensile modulus and breaking strength of PBST fibers increased, while elongation at break decreased. These were attributed to the increasing degree of orientation and crystallinity, which were resulted from the elevating tension of spinning line at higher take‐up velocity. To elucidate the effects of soft butylene succinate (BS) unit on the tensile and elastic properties of PBST fibers, poly(butylene terephthalate) (PBT) fibers were adopted as a comparison sample. The results showed that the combination of soft BS unit and hard BT unit for PBST fibers made contribution to the lower initial modulus, higher elongation at break and better elastic recovery than those of PBT fibers. Moreover, PBST fibers were found to undergo PBT‐like crystal form transition from α‐form to β‐form crystal structure under tension load through the measurement of WAXD. A relatively wider strain region for the crystal transition of PBST fibers also endowed them with higher elastic recoverability than PBT fibers. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Study on Influencing Factors of the Seaming of Knitted and Woven Fabrics

Clothing combining knitted and woven fabrics gets more and more favor of people. In this study, three knitted fabrics and three woven fabrics which are common on market were selected and seamed. The tensile breaking strength, elongation at break and the fracture reason of the joint of knitted and woven fabrics were tested using the one-way vertically stretching method. The test results were analyzed and it was found there are many factors affecting the seam strength of knitted and woven fabrics. Experiment shows that the main factors include: stitch density, joint method and choice of the joining material. The study of this subject provides the basis for designing better joint wear and improving sewing quality and efficiency.

Monochlorotriazinyl-β-cyclodextrin grafting onto polyester fabrics and films

The monochlorotriazinyl-β-cyclodextrin (MCT-β-CD) grafting onto polyester fabrics and films was carried out in an alkaline medium (saponification conditions with Na2CO3 respectively NaOH) at different temperatures (20 and 130°C) and treatment durations (30min, 1h, 3h, 5h, 24h) through a discontinuous procedure. The saponification and grafting were accomplished in two variants: individually and simultaneously respectively. It was noticed that the alkaline medium produces chemical and superficial modifications which make possible the MCT-β-CD grafting onto the polyester supports. This was rendered evident through FTIR analysis and SEM electron microscopy. The degree of grafting depends on the saponification/grafting conditions (the concentration of alkaline agents, time, temperature, MCT-β-CD concentration) and is reflected by the nitrogen content, hygroscopicity, air permeability, as well as by mechanical properties (tensile breaking strength, breaking elongation, breaking mechanical work and the specific mass work).

Histological and genetic characteristics associated with the seed-shattering habit of weedy rice (Oryza sativa L.) from Okayama, Japan

We aimed to elucidate the molecular nature of the seed-shattering habit of weedy rice Oryza sativa L. in Okayama Prefecture, Japan, which seems to be an “off-type” of the main rice varieties in Okayama. We performed time-course analyses of breaking tensile strength (BTS) and analyzed the histological features of pedicels; we also genotyped the seed-shattering genes qSH1 and sh4 of weedy rice accessions and rice cultivars. The BTS of weedy accessions and cultivars began to decrease simultaneously at three weeks after heading. The weedy accessions showed complete loss of BTS and grain dispersal at five weeks after heading. In contrast, the cultivars maintained a certain degree of BTS and did not exhibit grain dispersal. Pedicel structures, which affect BTS, differed between the weedy accessions and the cultivars. The weedy accessions had complete and cracked abscission layers, while the cultivars had incomplete and uncracked abscission layers; however, the qSH1 and sh4 sequences that influence the formation of the abscission layer showed no differences between the weedy accessions and cultivars. We surmise that the shattering habit of weedy rice in Okayama is caused by formation and degeneration of the abscission layer, mediated by unidentified shattering-related gene(s).

The Effect of Suture Size on Skin Wound Healing Strength in Rats

It is known that sutures enhance wound closure and promote healing. Sutures initially provide the mechanical strength to seal the wound and protect it from pathogens. Previous studies of suture mechanics focused on the material strength or knotting methods in vitro. Only a few studies have investigated the correlation between the healing strength of wounds and suturing. The purpose of this study was to investigate how the size of 4-0 and 6-0 nylon sutures affect the healing skin strength in rats. The temporal tensile breaking strength and normalized recovery index were measured by tensile testing. The histology observations were also obtained for structural correlation. Our results find that the mechanical strengths of both 4-0 and 6-0 groups do not have a statistical difference in the first two weeks. After four weeks, however, the breaking strengths of healing skin from the thicker 4-0 suture group are higher than the thinner 6-0 suture group. Histological observation showed more inflammatory cells in the 6-0 group than in the 4-0 group in the first week. These results reveal that small sutures can prolong healing time. The histological results are consistent with this finding, which demonstrated more inflammatory cells and extension of the inflammation phase.

The Effects of Recycled Acrylonitrile Butadiene Rubber Content and Maleic Anhydride Modified Polypropylene (PPMAH) on the Mixing, Tensile Properties, Swelling Percentage and Morphology of Polypropylene/Recycled Acrylonitrile Butadiene Rubber/Rice Husk Powder (PP/NBRr/RHP) Composites

The effect of recycled acylonitrile butadiene rubber (NBRr) content and PPMAH as a compatibilizer on the properties of PP/NBRr/RHP composites were examined using a Haake Rheomix at 180°C, 60 rpm for 9 min. Results showed that higher stabilization torque, Young's modulus and tensile strength were obtained for PPMAH compatibilized composite as compared to uncompatibilized composites. However, for elongation at break (Eb) and swelling percentage of compatibilized composites exhibited lower values than uncompatibilized composites. The increase of NBRr content in both compatibilized and uncompatibilized composites resulted in higher stabilization torques, swelling percentage and elongation at break but lower tensile strength and Young modulus. Tensile fractured surfaces observed by scanning electron microscopy showed good adhesion between NBRr and PP matrix and better dispersion of RHP for the compatibilized composites.

Inheritance of grain shedding and abscission layers in the cross combination between rice varieties

Seed shattering is an undesirable characteristic of rice cultivars affecting the loss of grain yield before and during harvesting. These grain losses are influenced by varietal characteristics. The histological peculiarities of the abscission region obtained were different among rice varieties, and had a close relationship with grain shedding. In order to obtain information for the breeding of new persistent shedding varieties, this study was designed to clarify the inheritance of grain shedding habits in relation to the abscission layer. In the cross combination of two easily shedding varieties, Milyang 23, a japonica-indica hybrid rice with cracked abscission layers and Ashahi, a japonica-type rice with uncracked abscission layers, the cracking of parenchymatous cells in the abscission layer was controlled by a single dominant gene. The breaking tensile strength coincided well with cracked and uncracked abscission layers. In four crosses between a persistent shedding variety without abscission layers and two easily shedding varieties with cracked abscission layers, and two medium shedding varieties with uncracked abscission layers, respectively, the formation of the abscission layer was controlled by a single dominant gene. The easily shedding and persistent shedding habits coincided well when the abscission layers were both present and absent. The easily shedding characteristics were dominant in cross combination. The close negative correlations were recognized between degrees of grain shedding and breaking tensile strengths.

Identification for quantitative trait loci controlling grain shattering in rice

Seed shattering is an important factor causing loss of grain yield before and during rice harvest. In the present study, the quantitative trait loci regarding shattering scale, breaking tensile strength (BTS) and abscission layer (AL), the parameters evaluating seed shattering habit by hand gripping, a digital force gauge and observation on AL, respectively, were identified by using an doubled haploid line (DHL) population from a cross between a loose-shattering type Tongil variety, ‘Samgang’, and a moderately difficult shattering japonica variety, ‘Nagdong’. Eight QTLs consisted in four QTLs for shattering scale, two QTLs for AL, each one QTL for pulling and bending strength were detected on six chromosomes, respectively. Among them, Qss1 with flanking markers RM6696 and RM476 explained 31% of phenotype variation in shattering scale. Furthermore, two new QTLs controlling shattering habit, Qss5-2 and Qal5-1, were located on chromosome 5 at the interval 5028–5037 and 5021-RM289. They explained 10% and 12% of phenotype variations, respectively. A total of eleven digenic epistatic loci were identified for four parameters. The identification of QTLs affecting seed shattering habits is favorable to thoroughly dissect the genetic mechanism of the shattering habit and to apply for marker-assisted selection in rice breeding system of specific regions.

Preparation and characterization of poly(vinyl butyral) hollow fiber membrane via thermally induced phase separation with diluent polyethylene glycol 200

Hydrophilic poly(vinyl butyral) (PVB) microporous hollow fiber membranes were prepared via thermally induced phase separation (TIPS), polyethylene glycol with molecular weight 200(PEG200) was used as diluent. The phase diagram of PVB/PEG200 system indicated L–L phase separation. The effects of preparation condition such as take-up speed, bore liquid flow rate, air-gap, and water bath temperature on the properties of the membrane were investigated. The results showed that PVB hollow fiber membrane prepared at air-gap 5 mm had a little greater tensile strength, breaking strength and elongation than those prepared at air-gap zero, and the former had a little greater rejection but smaller water permeate. The increase of the take-up speed led to the decrease of inner diameters and thickness, the increase of the bore liquid flow rate led to the increase of inner diameter and outer diameter, but the decrease of thickness.

Prediction of Handsheet Tensile Strength by Computational Simulation of Structure

To better understand the influence of fiber morphology on paper properties, we developed a novel 3-D computational simulator of paper structure, which was validated through experimental work. This simulator creates virtual pieces of handsheets using the size distributions of the fibers as the main inputs. Once the structure is generated, physical properties can be assessed. The main principles of the simulation and the results for one global texture property, the apparent density, were presented in a previous paper. In this paper, we focus on the prediction of the tensile breaking strength, the most commonly used physical property for paper characterization. The model is based on the model developed by Shallhorn and Karnis, which was adapted to take into account the fiber morphological distributions. It was successfully applied in the absence of fiber breaks during the test and validated with the 10 pulps used in the first part of the study.

Inheritance of the cracking characteristics of abscission layer and its relation with the degree of grain shedding

Seed shattering is an undesirable characteristic of rice cultivars affecting field loss of grain yield before and during harvesting. This research was designed to clarify the inheritance of the cracking characteristics of abscission layers formed between the rice grains and its pedicel using F2 populations derived from the crossing of Milyang 23 and Ashahi. The results indicated that the cracking characteristic of Milyang 23 was dominant to absence of cracking in Ashahi, and controlled by a single dominant gene. The degrees of grain shedding were somewhat related with the cracking characteristics of the abscission layer. The breaking tensile strengths closely correlated with the diameter of the supporting zone, the thickness of sclerenchyma tissue between the inner side of abscission layer and the central vascular tissues in the lemma side, and in the palea side, respectively. Some negative correlations were observed between the breaking tensile strengths and some agronomic traits such as plant height, culm length, panicle length, number of matured grains, and the ratio of fertility.

QTL mapping for agronomic and fibre traits using two interspecific chromosome substitution lines of Upland cotton

AbstractCS‐B14Sh and CS‐B22Sh are cotton interspecific chromosome substitution (CS)‐B lines, in which a pair of short arms of chromosome 14 and chromosome 22 were introgressed from Gossypium barbadense doubled‐haploid line 3‐79 with the background of Gossypium hirsutum line TM‐1, respectively. These two CS‐B lines were crossed with TM‐1, and segregating progenies (F2 and F2:3, respectively) were obtained. Phenotypic data of lint yield, yield‐related traits and fibre‐quality traits were collected from two trials. In the cross CS‐B14SH X TM‐1, QTL for boll weight (BW), lint percentage (LP), fibre upper half mean length (UHML), micronaire reading (MIC), and fibre breaking tensile strength (STR) were repeatedly detected. Alleles from 3‐79 decreased BW and MIC, but increased UHML and STR. In the cross CS‐B22Sh X TM‐1, QTL for BW, LP, UHML, MIC, STR, fibre elongation (EL),seed weight(SW), node of first fruiting branch (NFB) and fibre uniformity index (UI) were repeatedly detected, and alleles from 3‐79 decreased UHML, UI and STR, but increased NFB, SW, MIC and EL. QTL clusters were found in both populations.

Effect of Sustained-Release PDGF and TGF-β on Cyclophosphamide-Induced Impaired Wound Healing

Proper wound healing is pivotal to successful surgical outcomes. Previous studies have shown that growth factors can be used to enhance tissue repair under impaired healing conditions. However, because of limited delivery methods, the growth factors in these studies were delivered either topically or as a single local administration. Sixty Sprague-Dawley rats were divided equally into five groups and served as untreated normal controls or were implanted subcutaneously with a novel sustained-release drug delivery system through a dorsal incisional wound. This system delivered either transforming growth factor (TGF)-beta alone, platelet-derived growth factor (PDGF) alone, or TGF-beta and PDGF in combination, or served as unloaded sham controls. Wound healing was impaired in all treated rats by the administration of cyclophosphamide on days 1, 3, and 5. Wound tensile breaking strength was determined on days 4, 7, and 14. Sustained release of either TGF-beta or PDGF alone not only failed to improve the healing of cyclophosphamide-induced impaired wound healing but resulted in a paradoxical decrease in wound tensile breaking strength by day 7. However, the combined delivery of both TGF-beta and PDGF improved wound healing and significantly increased wound tensile breaking strength by day 7. Sustained-release delivery of TGF-beta and PDGF in combination, but not separately, by a subcutaneously implanted drug delivery system significantly improves cyclophosphamide-induced impaired wound healing in rats.

3-D computational simulation of paper handsheet structure and prediction of apparent density

To obtain a better understanding of the influence of fiber morphology on paper properties, a novel 3-D computational simulator of paper structure was developed and validated by experimental work. Depending on the wood species, the dimensions of the fibers may vary by a factor of two or three, which directly influences paper structure and properties. Using known fiber size distributions, the model creates virtual handsheets made of these pulps that can be visualized, manipulated, and qualitatively and quantitatively compared to real handsheets. For a given basis weight, the model calculates the number of fibers in the sample and the main textural properties: thick-ness, apparent density, porosity, and roughness. It also computes the relative bonded area and the apparent specific surface, which are important factors for assessing mechanical or transport properties. This simulator can be used to predict, in a very short time, the variation of a property as a function of changes in one morphological parameter such as fiber length. This paper presents the main principles of the simulation and the results for one global textural property, apparent density. A prediction of tensile breaking strength will be presented in a subsequent paper.

Comparative evaluation of the breaking strength of a simple mobile mandibular advancement splint

Mandibular advancement splints (MASs) are used to advance the mandible forward in patients with sleep-disordered breathing. The conventional rigid MAS restricts the movement of the mandible, and this immobility sometimes produces discomfort, including temporomandibular disorders. A simple method for fabricating a mobile MAS was devised, using a connector made from a polyethylene toothed belt, with the intention of making the MAS more comfortable. The experimental connector is easily constructed, inexpensive, and small enough for use as an intraoral MAS. To evaluate durability, the axial and diagonal tensile breaking strengths of the MAS, using high- or low-density polyethylene (HDPE or LDPE) lateral toothed belts, were compared with those of a conventional mobile MAS (Silensor). The values were compared by factorial analysis of variances and post hoc Scheffe's S multiple comparison intervals, with the value of statistical significance set at alpha = 0.05. In addition, the experimental LDPE connectors were clinically tested in 30 patients (23 males and 7 females aged 19-71 years) and evaluated. Compared with the Silensor, the experimental MAS exhibited sufficient breaking strength, especially when a diagonal tensile load was applied to mimic mandibular lateral translation. When examining the clinical evaluation between 3 and 4 months after insertion, no damage or failure was observed. The experimental connecting system may have clinical applications. To make the connector stronger for clinical use, HDPE should be used.

Effect of chemical treatments on water sorption and mechanical properties of flax fibres

In this work, in order to improve the adhesion between a polyester matrix (unsaturated polyester resin) and flax fibres ( Linum usitatissimum L.) and to increase their moisture resistance, chemical surface treatments have been used. These different treatments were performed with maleic anhydride (MA), acetic anhydride (Ac), silane (Si) and styrene (S). The modified flax fibres were characterized by means of infrared spectroscopy and surface energy analysis. The effect of these treatments on water sorption was investigated by using a gravimetric static equilibrium method. Water sorption isotherms were derived from kinetic data. The Park model based on the three sorption modes: Langmuir, Henry’s law and clustering, was successfully used to simulate the experimental sorption data. It was found that the (Ac) and particularly (S) treatments reduced overall water uptake of flax fibres. We show that tensile modulus, breaking strength and breaking strain depend on the chemical treatment used.

Effects of heat treatment on deformation characteristics of medium carbon steel

The effects of heat treatment on bending deformation, tensile strength and hardness of RST 37 medium carbon steels were investigated. Steel rod samples of ø12 mm diameter, 100 mm length, and % weight composition of 0.39 wt % C, 0.70 wt % Mn and 0.80 wt % Si and traces of alloying elements were tested. The samples were austenitized at 1123 K, annealed, normalized, quenched and tempered. Mechanical tests conducted on the sam-ples were bending, hardness, ultimate tensile strength, % elongation, breaking strength, yield strength, and yield ratio. The results showed that annealed, normalized and tempered samples exhibited high springback, while the hardened samples showed relatively low springback. As the tensile strength or yield strength increased, ductili-ty or total elongation decreased. The hardness was found to decrease with increasing springback. Journal of Applied Science and Technology Vol. 13 (1 & 2) 2008: pp. 81-85