High Strength Polyethylene Fiber Research Articles

Enhancement on compressive strength of Bangkok clay cement using novel high-strength polyethylene fibers

This study aims to investigate the effect of novel high-strength polyethylene fibers on the unconfined compressive strength (UCS) behavior of concrete produced with admixed Bangkok clay cement. Bangkok clay samples were prepared at a liquid limit of 88% and were added to ordinary Portland cement (OPC) at 2, 4, 6, 8 and 10% by weight; polyethylene fibers were also added at 0.5, 1.0, 1.5, 2.0 and 2.5% by volume. These samples were cured for 7, 14, and 28 days and subjected to an unconfined compressive test. From the test results, the cement content of 8% by weight was the optimum, and a polyethylene fiber content of 1% by volume is recommended. Moreover, the novel high-strength polyethylene fiber with 0.2 mm in diameter and 6 mm in length provided the maximum UCS value.

Green-Engineered Cementitious Composite Production with High-Strength Synthetic Fiber and Aggregate Replacement

Engineered cementitious composites (ECCs) are potentially useful structural reinforcement and repair materials. However, owing to their high costs and carbon emissions, they are not used extensively. To control these carbon emissions and costs, recycled fly ash cenospheres (FACs) and high-strength polyethylene (PE) fibers are used here to explore the possibility of developing green lightweight ECCs (GLECCs). A series of experiments was conducted to test the physical and mechanical properties of the developed GLECC and to evaluate the possibility of developing an GLECC. The crack width development of the GLECC was also analyzed using the digital image correlation method. The experimental results indicate the following: (1) The increase in FAC content and the decrease in PE content worsened the performance of GLECCs, but the resulting GLECCs still had significant strain-hardening properties; (2) The performance and costs of GLECCs can be balanced by adjusting the amount of FAC and PE. The maximum amount of FACs attainable is 0.45 (FAC/binder), and the required amount of PE fibers can be reduced to 1%. As a result, the cost was reduced by 40% and the carbon emission was reduced by 36%, while the compressive strength was greater than 30 MPa, the tensile strength was greater than 3.5 MPa, and the tensile strain was nearly 3%. (3) The width of the crack was positively correlated with the FAC content and negatively correlated with the fiber content. In the 0.8% strain range, the average crack width can be controlled to within 100 μm and the maximum crack width can be controlled to within 150 μm, with the performance still meeting the requirements of many applications.

Experimental investigation of the performance of concrete columns strengthened with fiber reinforced concrete jacket

This paper presents an experimental study on the axial compressive behavior of concrete columns retrofitted and confined by fiber-reinforced concrete (FRC) jackets. Three different engineered cementitious composite (ECC) mixes containing high-strength polyethylene fibers at three fiber volume fractions of 0%, 1%, and 2%, and one ultra-high performance cementitious composite (UHP) mix at fiber volume fraction of 4%, were prepared to produce FRC jackets around the core concrete. Horizontal stirrups were used in the FRC jackets with three different horizontal reinforcement ratios to investigate the effect of the level of confinement and the interaction between the conventional reinforcement and fibers. The results show that specimens having no fiber or stirrup in their retrofitting jacket exhibit a brittle behavior and only those containing both stirrup and fiber provide a ductile behavior. It was also observed that the lateral strain of the jacket layer at a given axial strain increased with an increase in the fiber content, indicating an increased rate of dilation for the jacket concrete at a higher fiber volume fraction. It was also found that the best solution to enhance both ductility and strength of columns using FRC jacket is to include a minimum of both fiber content and reinforcement in the jacketing layer. The observations of this study reveal the great potential of the use of FRC jackets in retrofitting of structural members, especially columns in seismic regions.

순수 폴리올레핀 소재용 청록색 염료의 합성

The 6 novel super hydrophobic bluish-green dyes, showing the maximum absorption at 600~650nm, were synthesized to dye polyolefin fibers such as polypropylene and high strength polyethylene fibers. Their absorption spectra appeared almost the same at visible range, which meant the length of alkyl substituents did not affect on color appearance of the dyes. The optimum length of alkyl group was determined as hexyl substituents from the practical point of view. From the dyeing results, the optimum dyeing condition was for 1 hour. The good fastness ratings to washing, rubbing were obtained showing 4-5 for both fibers. Light fastness was obtained also good rating 4 for both fibers.

Composite properties of high-strength polyethylene fiber-reinforced cement and cementless composites

This paper presents an experimental study of the composite properties of cement based- and alkali-activated ground-granulated blast furnace slag (GGBS) based composites reinforced by high-strength polyethylene fibers and a discussion of the different behaviors of the two types of binder-based composites. A series of experiments, including those to test the density, compression, and uniaxial tension, was performed to characterize the mechanical properties of the composite. The test results indicated that an alkali-activated GGBS composite shows a higher tensile strain capacity with smaller crack widths and crack spacings than a cement-based composite, although the alkali-activated GGBS composite showed lower compressive and lower tensile strength than the cement-based composite with the same water-to-binder ratio. It was also observed that the alkali-activated GGBS-based composite has higher ratio of the tensile strength to the compressive strength than the cement-based composite.

Numerical Analysis of Rigid and Flexible Reflection of Air Shock Wave

To study the difference between the reflected pressures of air shock wave on the rigid and flexible walls, the FE models of RC anti-blast wall and high-strength polyethylene fiber textile anti-blast wall were set up and the FSI solver of LS-DYNA was used to perform the numerical simulation. The TNT charge weight used in simulation is 5kg, 10kg, 15kg and 20kg, respectively. The peak reflected overpressures of air shock wave on the two kinds of walls were obtained. The variation of reflection coefficient of air shock wave on the anti-blast wall with scaled explosion distance and the wall stiffness was analyzed.

Treatment of nursing bottle caries with ribbond

Ribbond is a biocompatible, esthetic material made from high-strength polyethylene fiber. Lenowoven polyethylene ribbon (Ribbond) has been used successfully for tooth splinting, replacement of missing teeth, reinforcement of provisional acrylic resin fixed partial dentures, and orthodontic retention. This article presents the application of this polyethylene ribbon - RIBBOND - for the treatment of nursing bottle caries. To conclude we suggest that this combined technique of polyethylene fibers and composite material could be a very efficient alternative procedure to conventional treatment plans in pedodontic practice, with excellent esthetics and functional results.

Ribbond as an Esthetic Space Maintainer

Ribbond is a biocompatible, esthetic material made from a highstrength polyethylene fiber. Lenowoven polyethylene ribbon (Ribbond) has been used successfully for tooth splinting, replacement of missing teeth, reinforcement of provisional acrylic resin fixed partial dentures, and orthodontic retention. This paper presents the application of this polyethylene ribbon - RIBBOND as an esthetic space maintainer in pedodontic practice. We suggest that this combined technique of polyethylene fibers and composite material could be very efficient alternative procedure to conventional unesthetic space maintainers in pedodontic practice with excellent esthetics and functional results.

Thermal Conductivity of High Strength Polyethylene Fiber and its Application for Cryogenic Use

Thermal Conductivity of High Strength Polyethylene Fiber and its Application for Cryogenic Use

Ultra High Strength Polyethylene Fiber Applications for Heat Dissipating Fabrics

Ultra High Strength Polyethylene Fiber Applications for Heat Dissipating Fabrics

Thermal Conductivity of High-Strength Polyethylene Fiber and Applications for Cryogenic Use

The local temperature rise of the tape is one of instabilities of the conduction-cooled high temperature superconducting (HTS) coils. To prevent the HTS tape from locally raising a temperature, high thermal conductive fiber reinforced plastic was applied to coil bobbin or spacer for heat drain from HTS tape. The thermal conductivity of ramie fibers increases by increasing orientation of molecular chains with drawing in water, and decreases by chain scission withγ-rays irradiation or by bridge points in molecular chains with vapor-phase-formaldehyde treatments. Thermal conductivity of high strength ultra-high-molecular-weight (UHMW) polyethylene (PE) fiber increases lineally in proportion to tensile modulus and decreases by molecular chain scissions withγ-rays irradiation. This result suggested the contribution of the long extended molecular chains due to high molecular weight on the high thermal conductivity of high strength UHMW PE fiber. Thermal conductivity of high strength UHMW PE fiber reinforced plastics in parallel to fiber direction is proportional to the cross sectional ratio of reinforcement oriented in the conduction direction. Heat drain effect of high strength UHMW PE fiber reinforced plastic from HTS tape is higher than that of glass fiber reinforced plastic (GFRP) and lower than that of aluminum nitride (AlN). In the case of HTS coil, the thermal stability wound on coil bobbin made of high strength UHMW PE fiber reinforced plastic is good as that of AlN, and better than that of GFRP.

Creep forming of high strength polyethylene fiber prepregs for the production of ballistic protection helmets

Production of highly three dimensionally curved composite products with continuous fibers so far is dependent on drapability of the fibrous precursor. Drapability depends on the in-plane shear compliance of the precursor and on its bending flexibility. Elongation of the fibers usually gives a negligible contribution to drapability because high performance fibers typically show small elongations to failure. However, high strength polyethylene fibers are an exception. They may accumulate considerable creep elongation, provided that the loading time is sufficiently long. Choosing a proper processing temperature, somewhat below the melting temperature, allows that this sufficiently long processing time is still within the limits that are acceptable for industrial production. This paper explores the technique for creep forming of high strength polyethylene fiber prepregs for the production of full scale ballistic protection helmet shells. Such helmets show a highly three dimensionally curvature. It was found that such helmets can be made by creep-forming indeed. The helmets were free of wrinkles and showed excellent protection against supersonic projectiles. It was found to be very important that a homogeneous temperature distribution is provided during creep forming. Very high fiber tensile stresses occur during creep forming. Control of these high creep stresses is necessary.

The effect of gamma-radiation on polymer composites based on thermoplastic matrices

The effect of 60Co γ-radiation on polymer composite materials (PCMs) based on reinforcing glass cloth, polyethylene (PE), polyamide (PA) and polypropylene (PP) matrices has been studied. It has been found that PCMs based on more durable PP and PA matrices have a substantially lower radiation resistance as compared to their PE-matrix analogs. More stable carbon-reinforced plastics based on the PE matrix also have a lower radiation resistance as compared to fiberglass plastics. High-strength PE fiber, PE film, and PE-matrix composites behave in fundamentally different manners under the action of radiation.

Experimental setup to detect superconducting wire motion

An experimental setup was designed and fabricated to study superconducting wire motion under the influence of electromagnetic force. Experiments were conducted at 4.2 K by varying the experimental conditions such as the tension to the superconducting wire and different insulating materials at the interface of the superconducting wire and head part. The insulating materials used in the experiments were polyimide film and a high strength polyethylene fiber cloth, Dyneema. Details of the experimental setup and the test results are reported in this paper.

Application of High Strength Polyethylene Fiber for Superconducting Magnetic Energy Storage

Application of High Strength Polyethylene Fiber for Superconducting Magnetic Energy Storage

Development of High Performance Fiber Reinforced Composite with Negative Thermal Expansion Property

There are exists positive thermal expansion property for almost all materials. However, in many cases, the material property with negative thermal expansion is requested for engineering applications. This work is to develop high performance fiber-reinforced composites with negative thermal expansion by using high strength polyethylene fiber Dyneema®, high strength PBO fiber ZYLON®, aramid fiber Technora ® and carbon fibers.

High strength polyethylene fibers from high density polyethylene/organoclay composites

AbstractHigh strength fibers were prepared from high density polyethylene (HDPE)/organically modified montmorillonite (OMMT) composites. X‐ray diffraction study revealed that the composites were of conventional or phase‐separated type. As‐spun composite fibers were found to have higher drawability than as‐spun HDPE fiber. As a result of an increased drawability, fibers with much higher mechanical properties were obtained. The highest modulus and tensile strength obtained in the present study were 38 GPa and 1.7 GPa, respectively. Study of internal morphology suggests that the role of OMMT is to suppress a defect formation and allows the fiber to be drawn to higher draw ratio. Analysis of the mechanical properties of the fibers using a Griffith type relationship suggested that the fibers have much smaller defects and the predicted attainable strength for the fiber is much higher than that previously predicted for melt‐spun and hot drawn fiber. POLYM. ENG. SCI., 47:943–950, 2007. © 2007 Society of Plastics Engineers

The effect of γ‐irradiation on thermal strain of high strength polyethylene fiber at low temperature

AbstractTo understand the contribution to negative thermal expansion by the length of the molecular chains in high‐strength ultra‐high‐molecular‐weight polyethylene (UHMW‐PE) fiber, the thermal expansion coefficient in the range of low temperature was investigated for high‐strength UHMW‐PE fiber (Toyobo, Dyneema®; hereinafter abbreviated to DF), irradiated by γ‐rays (γ‐rays treatment) that induce the molecular scission. The molecular weight of DF decreased by γ‐ray treatment. X‐ray diffraction behavior did not change by γ‐ray treatment. The melting behavior observed by DSC showed the main chain scission of DF by γ‐ray treatment. The DFs, with and without γ‐ray treatment, expand by cooling down (negative thermal expansion). The change of negative thermal expansion of DF by γ‐ray treatment was small. It is suggested that negative thermal expansion does not change by only the molecular chain scission. These results suggested that the effect of negative thermal expansion of DF in the temperature range from 213 to 303 K by the molecular chain scissions is small and that the length of extended molecular chains contributes to a negative thermal expansion a little. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 204–209, 2006

Chain Orientation in Polyethylene Fibers Prepared by Ethylene Nanoextrusion Polymerization

Ethylene nanoextrusion polymerization has been demonstrated to be a novel nanofabrication concept for the preparation of polyethylene (PE) fibers directly from ethylene monomers without any post-processing procedures. For PE fibers, chain orientation is a critical parameter that affects performance and application of the fibrous materials. In this communication, we report an investigation on chain orientation in PE fibrous samples prepared through nanoextrusion polymerization using a two-dimensional wide angle X-ray diffraction (2D WAXRD) technique. Two types of fibrous samples, including individual microfibers and microfiber aggregates, were sampled randomly and studied. For individual PE microfibers, anisotropic diffraction patterns were observed, suggesting chain orientation along the microfiber axial direction. Some microfibers showed the most desired diffraction pattern often found in high-modulus high-strength PE fibers. These samples possessed a very high degree of chain orientation along the fiber axis. Owing to a random aggregation of anisotropic microfibers, microfiber aggregates exhibited isotropic diffraction patterns. This work provided further experimental evidence for the proposed nanoextrusion polymerization concept.

Thermal Expansion Coefficient of Unidirectional High-Strength Polyethylene Fiber Reinforced Plastics at Low Temperature

High-strength polyethylene fiber (Dyneema®, DF) has a negative linear thermal expansion coefficient in the direction of the fiber. Thermal expansion coefficients of fiber-reinforced plastics are of important applications in cryogenic use. The purpose of this study is to construct the engineering technology for the thermal strain of DF reinforced plastics (DFRP) for cryogenic engineering. In this study, we investigate the thermal expansion coefficient of unidirectional high-strength DF reinforced plastics (UD-DFRP) in which DFs with different tensile moduli (15–134 GPa) and thermal expansion coefficients are used. Furthermore, using the thermal expansion coefficient and tensile modulus of each DF fiber and the matrix resin, the thermal expansion coefficients of the DFRPs are estimated by the rule of mixtures and are compared with the measured values. The results indicate that the thermal expansion coefficient of UD-DFRP behaves in a similar way to that expected from calculations based on the rule of mixtures. In addition, relationships concerning the difference between the calculated and measured values, the difference in the thermal expansion coefficient of the fiber and the resin, and the surface treatment of the fiber (adhesivity), as well as the diameter of the fiber (the area of the interfacial bonding) are studied. The results show that all of these influence the thermal expansion coefficient of UD-DFRP. The design of negative thermal expansion coefficient of UD-DFRP is established.