Investigation on interlaminar properties of photopolymerizable resin repaired GFRPs during long-term acid ageing

2020 ◽  
Vol 34 (07n09) ◽  
pp. 2040037
Author(s):  
Zixuan Chen ◽  
Tianyu Yu ◽  
Yun-Hae Kim
Keyword(s):  
Ageing Time ◽  
Matrix Material ◽  
Operation Time ◽  
Acid Resistance ◽  
Complex Loading ◽  
Reinforced Plastics ◽  
Comprehensive Properties ◽  
Short Operation Time ◽  
Fiber Reinforced Plastics

Fiber reinforced plastics (FRPs) are extensively utilized in various applications due to their excellent comprehensive properties. However, the weak interlaminar property and durability of FRPs have been repeatedly mentioned as limitations in applications that include complex loading conditions. The remediation of FRPs has recently become a research focus for lifetime extension and strength reversion. Photopolymerizable resins, as a novel matrix material and an alternative for thermal polymerizable resins, have the advantages of short operation time, low price, and low equipment requirements. This study investigated the durability in long-term acid atmosphere exposure environment of photo and thermal polymerizable resin repaired GFRP. External glass fabric patches impregnated with the photo or thermal polymerizable resins were attached to pre-damaged fundamental specimens to conduct the remediation, followed by room temperature (RT) or UV irradiation for curing processing. The repaired specimens were positioned in the laboratory-fabricated hermetically-sealed condensation device. The 10 vol.% sulphuric acid (pH[Formula: see text][Formula: see text][Formula: see text]0.76) was chosen as the source to generate the acidic atmosphere. The total ageing time was sustained for eight weeks (over 1300 h), and ILSS and DCB tests were performed every seven days, together with morphology observation. Better interlaminar properties retention and stability were revealed after eight weeks ageing for UV repaired specimens. The hardener is a factor that tends to increase the acid penetration rate, which is thought of as the mechanism of the better acid resistance of the UV repaired specimens.

Effect of long climatic ageing on the microstructure of the surface of сarbon-fiber-reinforced plastics on base epoxy matrix

2019 ◽  
pp. 157-169 ◽  
Author(s):  
I. S. Deev ◽  
E. V. Kurshev ◽  
S. L. Lonsky
Keyword(s):  
Climatic Factors ◽  
Temperate Climate ◽  
Fiber Reinforced ◽  
Humid Climate ◽  
Climatic Zones ◽  
Reinforced Plastics ◽  
Carbon Plastics ◽  
Fiber Reinforced Plastics ◽  
Determining Factor

Studies and experimental data on the microstructure of the surface of samples of epoxy сarbon-fiber-reinforced plastics that have undergone long-term (up to 5 years) climatic aging in different climatic zones of Russia have been conducted: under conditions of the industrial zone of temperate climate (Moscow, MTsKI); temperate warm climate (Gelendzhik, GTsKI); a warm humid climate (Sochi, GNIP RAS). It is established that the determining factor for aging of carbon plastics is the duration of the complex effect of climatic factors: the longer the period of climatic aging, the more significant changes occur in the microstructure of the surface of the materials. The intensity of the aging process and the degree of microstructural changes in the surface of carbon plastics are affected by the features of the climatic zone. general regularities and features of the destruction of the surface of carbon plastics after a long-term exposure to climatic factors have been established on the basis of the analysis and systematization of the results of microstructural studies.

Influence of matrix systems on the deformation behavior of adaptive fiber-reinforced plastics

2020 ◽  
pp. 152808372092701
Author(s):  
Moniruddoza Ashir ◽  
Chokri Cherif
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Deformation Behavior ◽  
Matrix Material ◽  
Mixing Ratio ◽  
Fiber Reinforced ◽  
Reinforced Plastics ◽  
Bending Modulus ◽  
Hybrid Yarn ◽  
Fiber Reinforced Plastics

Adaptive structures contain actuators that enable the controlled modification of system states and characteristics. Furthermore, their geometric configuration as well as physical properties can be varied purposefully. The geometric configuration of adaptive fiber-reinforced plastics can be changed by varying the bending modulus of the matrix material. Hence, this research work presents the influence of thermosetting matrix material with different bending moduli on the deformation behavior of adaptive fiber-reinforced plastics. Firstly, shape memory alloys were converted into shape memory alloy hybrid yarn in order to realize this goal. Subsequently, shape memory alloy hybrid yarn was textile-technically integrated into reinforcing fabrics by means of weaving technology. The bending modulus of the thermosetting matrix material was changed by mixing modifier into it. The Seemann Corporation Resin Infusion Molding Process was used for infusion. Later, the deformation behavior of adaptive fiber-reinforced plastics was characterized. Results revealed that the maximum deformations of adaptive fiber-reinforced plastics with resin and modifier at a mixing ratio of 9:1 and 8:2 were increased to 34% and 63%, respectively, compared to adaptive fiber-reinforced plastics infiltrated by the reference resin. The maximum deformation speed during heating and cooling of adaptive fiber-reinforced plastic with the mixing ratio of resin and modifier at a value of 8:2 were 41.17 mm/s and 26.89 mm/s, respectively.

A novel model of acellular dermal matrix plug for anal fistula treatment. Report of a case and surgical consideration based on first utility in Poland

2017 ◽  
Vol 89 (4) ◽  
pp. 52-55 ◽  
Author(s):  
Adam Bobkiewicz ◽  
Łukasz Krokowicz ◽  
Maciej Borejsza-Wysocki ◽  
Tomasz Banasiewicz
Keyword(s):  
Anal Fistula ◽  
Operation Time ◽  
Acellular Dermal Matrix ◽  
Dermal Matrix ◽  
Polish Experience ◽  
Short Operation Time ◽  
New Type ◽  
Fistula Treatment ◽  
Long Term Observation

Anal fistula (AF) is a pathological connection between anus and skin in its surroundings. The main reason for the formation of anal fistula is a bacterial infection of the glands within the anal crypts. One of the modern techniques for the treatment of fistulas that do not interfere with the sphincters consists in implantation of a plug made from collagen material. We are presenting the first Polish experience with a new model of biomaterial plug for the treatment of anal fistula. We also point out key elements of the procedure (both preoperative and intraoperative) associated with this method. In the authors’ opinion, the method is simple, safe and reproducible. Innovative shape of the plug minimizes the risk of its migration and rotation. It also perfectly blends with and adapts to the course and shape of the fistula canal, allowing it to become incorporated and overgrown with tissue in the fistula canal. The relatively short operation time, minor postoperative pain and faster convalescence are with no doubt additional advantages of the method. Long-term observation involving more patients is essential for evaluation of the efficacy of the treatment of fistulas with the new type of plug.

scholarly journals On the Ablation Behavior of Carbon Fiber-Reinforced Plastics during Laser Surface Treatment Using Pulsed Lasers

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5682
Author(s):  
Jana Gebauer ◽  
Maximilian Burkhardt ◽  
Volker Franke ◽  
Andrés Fabián Lasagni
Keyword(s):  
Carbon Fiber ◽  
Laser Treatment ◽  
Carbon Fibers ◽  
Matrix Material ◽  
Pulsed Lasers ◽  
Fiber Reinforced ◽  
Carbon Fiber Reinforced Plastics ◽  
Reinforced Plastics ◽  
Matrix Removal ◽  
Fiber Reinforced Plastics

This contribution discusses the ablation phenomena observed during laser treatment of carbon fiber-reinforced plastics (CFRPs) with pulsed lasers observed employing laser sources with wavelengths of 355 nm, 1064 nm and 10.6 µm and pulse durations from picoseconds (11 ps) to microseconds (14 µs) are analyzed and discussed. In particular, the threshold fluence of the matrix material epoxy (EP) and the damage threshold of CFRP were calculated. Moreover, two general surface pretreatment strategies are investigated, including selective matrix removal and structure generation through indentation (ablation of both, matrix material and fibers) with a cross-like morphology. The surfaces obtained after the laser treatment are characterized by means of optical and scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy is employed for the analysis of composite and constituent materials epoxy and carbon fibers. As a result, different ablation mechanisms, including evaporation and delamination are observed, depending on the employed laser wavelength and pulse duration. For both 355 nm and 1064 nm wavelength, the laser radiation produces only partial ablation of the carbon fibers due to their higher absorption coefficient compared to the epoxy matrix. Although a selective matrix removal without residues is achieved using the pulsed CO2 laser. Differently, both constituent materials are ablated with the nanosecond pulsed UV laser, producing indentations. The sum of the investigations has shown that existing theories of laser technology, such as the ablation threshold according to Liu et al., can be applied to composite materials only to a limited extent. Furthermore, it has been found that the pronounced heterogeneity of CFRP mostly leads to an inhomogeneous ablation result, both when creating grooves and during selective matrix removal, where the carbon fibers influence the ablation result by their thermal conductivity, depending on fiber direction. Finally, despite the material inhomogeneity, a scanning strategy has been developed to compensate the heterogeneous ablation results regarding structure depth, width and heat affected zone.

Investigation on the Alkali-Resistance Properties of Basalt Fiber Reinforced Plastics Bars in Concrete

2011 ◽  
Vol 284-286 ◽  
pp. 182-186 ◽  
Author(s):  
Jun Long Zhou ◽  
Chun Xia Xu ◽  
Shi Yong Jiang ◽  
Bing Hong Li ◽  
Zhong Wen Ou
Keyword(s):  
High Temperature ◽  
Basalt Fiber ◽  
Alkali Resistance ◽  
Fiber Reinforced ◽  
Reinforced Plastics ◽  
Temperature Method ◽  
New Type ◽  
Fiber Reinforced Plastics ◽  
Marine Engineering

As a new type of building material, Basalt Fiber Reinforced Plastics is employed in concrete in place of steel reinforcement under such strongly-corrosive environment as marine engineering projects to avoid durability problem caused by corrosion. But BFRP bars’ alkali-resistance must be considered and studied. In this study, BFRP was soaked in saturated Ca(OH)2 solution and its tensile strength was measured through long-period immersion and high-temperature immersion experiments respectively. Besides, accelerated high-temperature method was adopted to detect its main ingredients: continuous Basalt fiber and resin. The results indicate that BFRP has poor alkali-resistance and its alkali-resistance must be improved if it is applied in concrete for long-term purpose.

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