Tensile Strength of Surface Treated PBO Fiber

2015 ◽  
Vol 815 ◽  
pp. 622-628 ◽  
Author(s):  
Gang Shi ◽  
Su Ju ◽  
Chun Fang Huang ◽  
Da Zhi Jiang ◽  
Jian Wei Zhang
Keyword(s):  
Tensile Strength ◽  
High Performance ◽  
Fiber Surface ◽  
Interface Energy ◽  
Plasma Modification ◽  
Interface Properties ◽  
Weibull Analysis ◽  
Combined Treatments ◽  
Pbo Fiber ◽  
The Individual

Poly p-phenylene benzobisoxazole (PBO) fiber is a kind of organic fiber with high performance, but the properties of the interface between PBO fiber and resin are poor, which limit its application in the field of composite materials. Therefore, the surface modification methods were employed to enhance the interface properties, which could damage the fiber. This article assessed the influence of plasma modification, γ-ray irradiation, coupling agent, acid treatment and combined treatments on the strength of PBO fiber filament, and investigated its tensile strength with Weibull analysis. Through observation of fiber surface by SEM，it can be found that some combined treatments caused less damage to PBO fiber compared to the individual treatments. This indicates that if combining the different treatments appropriately, the interface energy of PBO fiber will increase, with the excellent mechanical properties well retained

scholarly journals Kenaf Bast Fibers—Part II: Inorganic Nanoparticle Impregnation for Polymer Composites

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Jinshu Shi ◽  
Sheldon Q. Shi ◽  
H. Michael Barnes ◽  
Mark F. Horstemeyer ◽  
Ge Wang
Keyword(s):  
Tensile Strength ◽  
Polymer Composites ◽  
Tensile Modulus ◽  
Fiber Surface ◽  
Bast Fibers ◽  
Inorganic Nanoparticle ◽  
The Individual ◽  
Kenaf Fibers ◽  
Kenaf Bast Fibers ◽  
Kenaf Bast

The objective of this study was to investigate an inorganic nanoparticle impregnation (INI) technique to improve the compatibility between kenaf bast fibers and polyolefin matrices. The Scanning Electron Microscopy (SEM) was used to examine the surface morphology of the INI-treated fibers showing that the CaCO3nanoparticle crystals grew onto the fiber surface. Energy-dispersive X-ray spectroscopy (EDS) was used to verify the CaCO3nanoparticle deposits on the fiber surface. The tension tests of the individual fiber were conducted, and the results showed that the tensile strength of the fibers increased significantly (more than 20%) after the INI treatments. Polymer composites were fabricated using the INI-treated fiber as reinforcement and polypropylene (PP) as the matrix. The results showed that the INI treatments improved the compatibility between kenaf fibers and PP matrix. The tensile modulus and tensile strength of the composites reinforced with INI-treated fibers increased by 25.9% and 10.4%, respectively, compared to those reinforced with untreated kenaf fibers.

Enhanced UV Stability of PBO Fibers by Using Benzotriazole UV Absorber

2012 ◽  
Vol 522 ◽  
pp. 931-934 ◽  
Author(s):  
Bo Song ◽  
Ling Hui Meng ◽  
Yu Dong Huang
Keyword(s):  
Tensile Strength ◽  
Intrinsic Viscosity ◽  
Fiber Surface ◽  
Experimental Results ◽  
Uv Exposure ◽  
Uv Absorber ◽  
Pbo Fiber ◽  
Significant Change ◽  
Surface Morphologies ◽  
Strength Retention

In the present research, a sizing agent containing benzotriazole UV absorber was used as coating to enhance the UV stability of PBO fibers. The sizing coating was characterized by XPS and SEM. The effect of UV absorber on UV stability of PBO fibers was studied by an accelerated photo-aging method. The experimental results show that UV stability of coated PBO fibers was obviously improved compare to uncoated PBO fibers. After 480 h of UV exposure, the tensile strength retention and intrinsic viscosity retention of coated PBO fibers was higher than that of original PBO fibers. SEM photograph shows that no significant change of surface morphologies, meanwhile some latitudinal crack appeared on the original PBO fiber surface.

Improvement of PBO fiber surface and PBO/PPESK composite interface properties with air DBD plasma treatment

2011 ◽  
Vol 44 (5) ◽  
pp. 548-553 ◽  
Author(s):  
Qian Wang ◽  
Ping Chen ◽  
Caixia Jia ◽  
Mingxin Chen ◽  
Bin Li
Keyword(s):  
Plasma Treatment ◽  
Fiber Surface ◽  
Interface Properties ◽  
Dbd Plasma ◽  
Composite Interface ◽  
Pbo Fiber

scholarly journals THE ALKALI TREATMENT PARAMETERS USING TAGUCHI MODEL IN ORDER TO OBTAIN THE OPTIMUM TENSILE STRENGTH OF SINGLE KENAF FIBER

2017 ◽  
Vol 7 (2) ◽  
pp. 49
Author(s):  
Henny Pratiwi
Keyword(s):  
Tensile Strength ◽  
Analysis Of Variance ◽  
High Performance ◽  
Optimal Parameter ◽  
Alkali Treatment ◽  
Fiber Surface ◽  
Taguchi Methods ◽  
Naoh Solution ◽  
The Fourier Transform ◽  
Kenaf Fibers

The development of high-performance engineering products made from natural resources is increasing worldwide. Kenaf plants have been extensively exploited over the past few years. Chemical treatment is considered to modify the fiber surface properties. In this study, kenaf bast fibers were treated with various concentrations of NaOH with different immersed time, immersed temperature, and dried temperature. Fiber bundle tensile were performed to evaluate the effect of treatments on the fiber tensile strength. Taguchi Methods are used in order to obtain the optimal parameter which could affect the tensile strength of kenaf fibers. Three-Level Orthogonal array is used to design the experiment. Finally, the experimental results will be evaluated using analysis of variance (ANOVA). The analysis of variance (ANOVA) shows that the most significant alkali parameter is NaOH concentration, which accounts for 40.19 percent of the total. It is also found that the optimum treatment is kenaf immersed in 3 wt. percent NaOH solution for 1 hour at 33 degrees celcius and dried at 60 degrees celcius which is supported by the Fourier Transform Infrared Spectroscopy.

Morphology of High-Performance Rigid-Rod Polymer Fibers and Molecular Composites

1989 ◽  
Vol 47 ◽  
pp. 338-339
Author(s):  
W.W. Adams ◽  
S. J. Krause
Keyword(s):  
Tensile Strength ◽  
High Performance ◽  
Liquid Crystalline ◽  
Molecular Level ◽  
Synergistic Effects ◽  
Tensile Modulus ◽  
Commercial Development ◽  
The Matrix ◽  
Molecular Composites ◽  
Rigid Rod

Rigid-rod polymers such as PBO, poly(paraphenylene benzobisoxazole), Figure 1a, are now in commercial development for use as high-performance fibers and for reinforcement at the molecular level in molecular composites. Spinning of liquid crystalline polyphosphoric acid solutions of PBO, followed by washing, drying, and tension heat treatment produces fibers which have the following properties: density of 1.59 g/cm3; tensile strength of 820 kpsi; tensile modulus of 52 Mpsi; compressive strength of 50 kpsi; they are electrically insulating; they do not absorb moisture; and they are insensitive to radiation, including ultraviolet. Since the chain modulus of PBO is estimated to be 730 GPa, the high stiffness also affords the opportunity to reinforce a flexible coil polymer at the molecular level, in analogy to a chopped fiber reinforced composite. The objectives of the molecular composite concept are to eliminate the thermal expansion coefficient mismatch between the fiber and the matrix, as occurs in conventional composites, to eliminate the interface between the fiber and the matrix, and, hopefully, to obtain synergistic effects from the exceptional stiffness of the rigid-rod molecule. These expectations have been confirmed in the case of blending rigid-rod PBZT, poly(paraphenylene benzobisthiazole), Figure 1b, with stiff-chain ABPBI, poly 2,5(6) benzimidazole, Fig. 1c A film with 30% PBZT/70% ABPBI had tensile strength 190 kpsi and tensile modulus of 13 Mpsi when solution spun from a 3% methane sulfonic acid solution into a film. The modulus, as predicted by rule of mixtures, for a film with this composition and with planar isotropic orientation, should be 16 Mpsi. The experimental value is 80% of the theoretical value indicating that the concept of a molecular composite is valid.

EFFECT OF ZINC DITHIOCARBAMATES AND THIAZOLE-BASED ACCELERATORS ON THE VULCANIZATION OF NATURAL RUBBER

2012 ◽  
Vol 85 (1) ◽  
pp. 120-131 ◽  
Author(s):  
Md. Najib Alam ◽  
Swapan Kumar Mandal ◽  
Subhas Chandra Debnath
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Reaction Mechanism ◽  
Natural Rubber ◽  
High Performance ◽  
Binary Systems ◽  
Synergistic Activity ◽  
Tetramethylthiuram Disulfide

Abstract Several zinc dithiocarbamates (ZDCs) as accelerator derived from safe amine has been exclusively studied in the presence of thiazole-based accelerators to introduce safe dithiocarbamate in the vulcanization of natural rubber. Comparison has been made between conventional unsafe zinc dimethyldithiocarbamate (ZDMC) with safe novel ZDC combined with thizole-based accelerators in the light of mechanical properties. The study reveals that thiuram disulfide and 2-mercaptobenzothiazole (MBT) are always formed from the reaction either between ZDC and dibenzothiazyledisulfide (MBTS) or between ZDC and N-cyclohexyl-2-benzothiazole sulfenamide (CBS). It has been conclusively proved that MBT generated from MBTS or CBS reacts with ZDC and produces tetramethylthiuram disulfide. The observed synergistic activity has been discussed based on the cure and physical data and explained through the results based on high-performance liquid chromatography and a reaction mechanism. Synergistic activity is observed in all binary systems studied. The highest tensile strength is observed in the zinc (N-benzyl piperazino) dithiocarbamate-accelerated system at 3:6 mM ratios. In respect of tensile strength and modulus value, unsafe ZDMC can be successfully replaced by safe ZDCs in combination with thiazole group containing accelerator.

Study of Transcrystallization in Polymer Composites

1989 ◽  
Vol 170 ◽  
Author(s):  
Benjamin S. Hsiao ◽  
J. H. Eric
Keyword(s):  
Thermal Conductivity ◽  
Free Energy ◽  
Carbon Fiber ◽  
Plasma Treatment ◽  
Polymer Composites ◽  
High Performance ◽  
Interfacial Strength ◽  
Fiber Surface ◽  
Semicrystalline Polymers ◽  
First Case

AbstractTranscrystallization of semicrystalline polymers, such as PEEK, PEKK and PPS, in high performance composites has been investigated. It is found that PPDT aramid fiber and pitch-based carbon fiber induce a transcrystalline interphase in all three polymers, whereas in PAN-based carbon fiber and glass fiber systems, transcrystallization occurs only under specific circumstances. Epitaxy is used to explain the surface-induced transcrystalline interphase in the first case. In the latter case, transcrystallization is probably not due to epitaxy, but may be attributed to the thermal conductivity mismatch. Plasma treatment on the fiber surface showed a negligible effect on inducing transcrystallization, implying that surface-free energy was not important. A microdebonding test was adopted to evaluate the interfacial strength between the fiber and matrix. Our preliminary results did not reveal any effect on the fiber/matrix interfacial strength of transcrystallinity.

Improving Efficiency in Robot Assisted Belt Grinding of High Performance Materials

2014 ◽  
Vol 907 ◽  
pp. 139-149 ◽  
Author(s):  
Eckart Uhlmann ◽  
Florian Heitmüller
Keyword(s):  
Gas Turbines ◽  
High Performance ◽  
Scale Effects ◽  
Turbine Blades ◽  
Repair Process ◽  
Industrial Robots ◽  
Robot Assisted ◽  
Belt Grinding ◽  
Economy Of Scale ◽  
The Individual

In gas turbines and turbo jet engines, high performance materials such as nickel-based alloys are widely used for blades and vanes. In the case of repair, finishing of complex turbine blades made of high performance materials is carried out predominantly manually. The repair process is therefore quite time consuming. And the costs of presently available repair strategies, especially for integrated parts, are high, due to the individual process planning and great amount of manually performed work steps. Moreover, there are severe risks of partial damage during manually conducted repair. All that leads to the fact that economy of scale effects remain widely unused for repair tasks, although the piece number of components to be repaired is increasing significantly. In the future, a persistent automation of the repair process chain should be achieved by developing adaptive robot assisted finishing strategies. The goal of this research is to use the automation potential for repair tasks by developing a technology that enables industrial robots to re-contour turbine blades via force controlled belt grinding.

Adaptive Precision Block-Jacobi for High Performance Preconditioning in the Ginkgo Linear Algebra Software

2021 ◽  
Vol 47 (2) ◽  
pp. 1-28
Author(s):  
Goran Flegar ◽  
Hartwig Anzt ◽  
Terry Cojean ◽  
Enrique S. Quintana-Ortí
Keyword(s):  
Linear Algebra ◽  
Graphics Processing Units ◽  
High Performance ◽  
Numerical Algorithms ◽  
Mixed Precision ◽  
Before And After ◽  
Memory Accesses ◽  
Specialized Hardware ◽  
The Individual ◽  
Graphics Processing

The use of mixed precision in numerical algorithms is a promising strategy for accelerating scientific applications. In particular, the adoption of specialized hardware and data formats for low-precision arithmetic in high-end GPUs (graphics processing units) has motivated numerous efforts aiming at carefully reducing the working precision in order to speed up the computations. For algorithms whose performance is bound by the memory bandwidth, the idea of compressing its data before (and after) memory accesses has received considerable attention. One idea is to store an approximate operator–like a preconditioner–in lower than working precision hopefully without impacting the algorithm output. We realize the first high-performance implementation of an adaptive precision block-Jacobi preconditioner which selects the precision format used to store the preconditioner data on-the-fly, taking into account the numerical properties of the individual preconditioner blocks. We implement the adaptive block-Jacobi preconditioner as production-ready functionality in the Ginkgo linear algebra library, considering not only the precision formats that are part of the IEEE standard, but also customized formats which optimize the length of the exponent and significand to the characteristics of the preconditioner blocks. Experiments run on a state-of-the-art GPU accelerator show that our implementation offers attractive runtime savings.

Sign in / Sign up

Export Citation Format

Share Document