scholarly journals Behavior of Polymer Materials Exposed to Aging in the Swimming Pool: Focus on Properties That Assure Comfort and Durability

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2414
Author(s):  
Ivana Salopek Čubrić ◽  
Goran Čubrić ◽  
Vesna Marija Potočić Matković
Keyword(s):  
Fluid Transport ◽  
Negative Impact ◽  
Microscopic Analysis ◽  
Tensile Tests ◽  
Polymer Materials ◽  
Breaking Force ◽  
Textile Materials ◽  
Few Data ◽  
Effects Of Aging

The degradation of polyamide (PA) and polyester (PES) polymers is under intense study due to growing concerns about the accumulation of plastics in soils and oceans. Previous studies confirm that ageing degrades PA and PES at the molecular level. However, researchers have not addressed the development of protocols for aging textile materials in swimming pools, and few data are available on the effects of aging on comfort and durability. This research addresses the development of the aging protocol for PA and PES swimwear materials, its implementation, and the evaluation of properties that assure comfort and durability after specific periods of exposure. The tests include microscopic analysis, tensile tests, determination of fluid transport phases and drying period. The results revealed changes in the surface of the material in terms of fibrillation (more pronounced after outdoor aging). There is a positive correlation between the exposure duration and the breaking force (R2 ranges from 0.85 to 0.98), with a stronger correlation for the PA materials. The decrease in breaking force due to aging is up to 40%, indicating significantly reduced durability. The change in breaking force follows the changes in mass (R2 = 0.867). In terms of comfort assurance, outdoor aging of materials should have a greater negative impact than indoor ageing.

scholarly journals РОЗРИВАЛЬНІ ХАРАКТЕРИСТИКИ КОМПЛЕКСНОЇ ПОЛІЕТИЛЕНОВОЇ НИТКИ

2022 ◽  
pp. 51-59
Author(s):  
SVITLANA BOBROVA ◽  
OKSANA DMYTRYK ◽  
LIUDMYLA HALAVSKA ◽  
TETIANA YELINA
Keyword(s):  
Linear Density ◽  
Materials Science ◽  
Breaking Load ◽  
Breaking Force ◽  
Factors Affecting ◽  
Textile Materials ◽  
Modeling Systems ◽  
Analysis And Synthesis ◽  
Straight Segments

Purpose. To investigate the influence of the number of threads resisting to break, the griping length, and the change in the position of the interlacing point when threading with a loop the breaking characteristics of complex polyethylene threads in the form of a loop.Methodology. In the course of the research, experimental research methods were used to determine the breaking characteristics of high molecular weight polyethylene threads on a WDW-5ES tensile machine in accordance with DSTU ISO 2062: 2004, the main provisions of textile materials science and knitting theory, methods of analysis and synthesis of the results obtained. Results. Based on the results of the studies, the influence of different factors on the breaking characteristics of complex multifilament threads was determined, namely: the influence of the number of threads resting on the break, the griping length and the change in the position of the weave point when threading with a loop. In the course of research, the griping length was changed in the range from 25mm to 300mm, and with a stable griping length (100 mm), the location of the thread weave point relative to the lower grip (25mm, 50mm, 75mm) was changed. It has been found that the breaking characteristics of a complex polyethylene yarn are influenced by both the griping length and the location of the weave point in the case of a loop-shaped break. The magnitude of the specific breaking force in the study of loop-shaped rupture is greater than in the study of straight segments of the thread. This is due to parallelization and compaction of the filaments due to the presence of the weave point on the thread that resists tearing. Scientific novelty. Regularities of the effect of griping length, linear density, and location of the point of weave of the complex high molecular threads in relation to the downer and upper grip are established provided that the griping length (100 mm) remains unchanged on the value of breaking load and elongation.Practical significance. Determination of the factors affecting the breaking characteristics of a complex polyethylene yarn will allow in the future, at the stage of designing the structure of knitwear in computer 3D modeling systems, to provide for the magnitude of the breaking force.

scholarly journals Interrelation Between Tensile Properties of Yarns and Woven Fabrics with These Yarns

2019 ◽  
Vol 19 (4) ◽  
pp. 387-393
Author(s):  
Eglė Kumpikaitė ◽  
Indrė Tautkutė-Stankuvienė ◽  
Dovilė Redeckienė
Keyword(s):  
Tensile Properties ◽  
Raw Materials ◽  
Tensile Tests ◽  
Woven Fabrics ◽  
Breaking Force ◽  
Elongation At Break ◽  
Natural Silk ◽  
Cotton Yarns ◽  
Almost All

Abstract The main parameters of tensile tests for fabrics and yarns are the breaking force and the elongation at break. The aim of this investigation was to find the relation between the tensile properties of yarns and woven fabrics for different natural raw materials. Manmade bamboo, natural single flax, blended plied flax and natural silk yarns, plied combed cotton yarns, blended plied cotton, and polyester yarns were used for the research. The warp of almost all fabrics, except of one fabric, was from flax. This fabric was woven using blended flax and silk yarns in the warp. Weft yarns were more various – yarns of one kind were used in the weft for certain fabrics; yarns of two kinds were used in 1:1 repeats in other fabrics. It was established that the breaking force for both woven fabrics and yarns increases when the elongation at break increases. The relationships between the tensile parameters of yarns and woven fabrics were established. The results showed weak dependence between the tensile parameters of yarns and fabrics because the coefficients of determination of the dependences are small.

DEFINITION OF TIME SPENT ON REPAIR OF BUS TRANSMISSION UNITS TAKING INTO ACCOUNT TECHNOLOGICAL EQUIPMENT RELIABILITY

2020 ◽  
Vol 2020 (9) ◽  
pp. 29-33
Author(s):  
Sergey Bulatov
Keyword(s):  
Negative Impact ◽  
Probabilistic Method ◽  
Technological Equipment ◽  
Quality And Safety ◽  
Transmission Unit ◽  
Equipment Reliability ◽  
Hours Of Work ◽  
Definition Of ◽  
Time Decrease

The paper purpose is the effectiveness estimation in the technological equipment use, taking into account its reliability and productivity for defective transmission units of buses. The problem consists in the determination of time to be spent on repair of bus transmission units taking into account technological equipment reliability. In the paper there is used a probabilistic method for the prediction bus transmission units, and also a method of the dynamics of averages which allow ensuring minimum of costs for units downtime during repair and equipment cost. The need for repair of transmission units (gear box) arises on an average after 650 hours, the average productivity of the bench makes 4.2 bus / hour. The bench fails on the average after 4600 hours of work, the average time of the bench makes 2 hours. In such a way the solution of the problem specified allows analyzing the necessity of time decrease for transmission unit repair to avoid long downtimes of buses in repair areas without negative impact upon high repair quality and safety during the further operation.

Changes of some sewage sludge parameters prepared with an ultrasonic field

1997 ◽  
Vol 36 (11) ◽  
pp. 101-106 ◽  
Author(s):  
January Bien ◽  
Lidia Wolny
Keyword(s):  
Sewage Sludge ◽  
Microscopic Analysis ◽  
Chemical Compounds ◽  
Ultrasonic Field ◽  
Water Removal ◽  
Vacuum Filter ◽  
Additional Criterion ◽  
New Methods ◽  
Sludge Conditioning

Studies of sewage sludge conditioning by ultrasonic field concentrate on determination of the increase of water removal effect, which depends on kind of sludge and chemical compounds used in the dewatering process. An attempt was made to find new methods of sludge preparation before dewatering. Tests presented here focused on digested and difficult dewatered sludge. The sludge was dewatered on a vacuum filter after conditioning with polyelectrolytes and the ultrasonic field. The microscopic analysis was an additional criterion to evaluate changes in the sludge structure after preparation. The polyelectrolyte dose of 3 mg/g d.m. sonicated within 15 sec. resulted in the 50% decrease of sludge volume. Results presented confirmed our previous experiences, concerning the relation between conglomerates of sludge and the effect of dewatering.

Sign in / Sign up

Export Citation Format

Share Document