Polymer Composite Systems in Pipeline Repair: Design, Manufacture, Application, and Environmental Impacts

Polymer Composite Systems for Pipeline Repair: Design, Manufacture, Application, and Environmental Impacts delivers the latest developments in nanomaterials, specifically polymers and composites that can support pipeline repair in an effective and more environmentally-sound way. Edited by a diverse worldwide group of contributors, the reference touches on design and manufacturing techniques, patch configurations, hybrid pipes used in harsher environments, and damage detection techniques. High temperature, marine, and cold fluids are also included. Rounding out with economic and environmental impact assessments, this book gives today’s oil and gas pipeline engineers an impactful and sustainable tool to safely repair pipelines.

• Present readers with detailed knowledge on the design, manufacture and application of composite systems used to repair damage in pipelines
• Assesses the environmental impacts on pipeline repairs using nano materials
• Provides the most recent developments in the research of polymers, blends and composites for repair applications
• Bridge theory and practice on the most recent developments in the research of polymers, blends and composites, with applicable case studies and contributions from a diverse group of worldwide contributors

• Language: English
• Publisher: Elsevier Science
• Release date: May 30, 2023
• ISBN: 9780323950947

Book preview

Chapter One

Recent advancements in polymer composites for damage repair applications

V Bhuvaneswari,    Department of Mechanical Engineering, KPR Institute of Engineering and Technology, Coimbatore, Tamil Nadu, India

Abstract

Composites are used worldwide for their multiple abilities. In general, focus is more toward polymer matrix composites due to their availability in plenty, easy extraction without affecting the vicinity, and flexible manufacturability. The basic ability of polymer composites is light weight, so adoptability is better for versatile applications. In this chapter, the focus is toward a specific application, which is the damage-repairing ability of polymer composite. The damage repairing ability is neither by itself nor through external agents, both are discussed but predominantly self-healing . This ability makes the polymer composites to widen their applications to many domains therein, and it can save cost, human life, and so on.

Keywords

Carbon nanotube; nanofiller; carbon composites; carbon fiber; nanofibers; polymer composite

1.1 Introduction

Materials made of polymers have been obligated to accomplish under extreme mechanical, thermal, and chemical stress in the automotive, aerospace, and space industries. It is both expensive and time- consuming to replace or repair damaged components in many cases. Damage to polymer structures can be divided into two categories: macro and microscopic. Impact and internal stresses can cause microscopic damage such as microcracking. It is a leading cause of failure, even though undetectable, and the resulting structural fragmentation reduces mechanical properties such as strength, stiffness, and dimensional stability (Narin, 2000; Pang & Bond, 2005). Traditionally, damage at the macroscopic level is discovered by visual inspection and repaired. However, detecting microscopic and internal destruction requires the use of damage inspection methods including ultrasonic waves and radiography. However, because of the constraints in the resolution among these methodologies, damages such as microcracking cannot be detected and therefore cannot be repaired. Furthermore, it is exceptionally complicated to recognize and repair cracks, structural defects, and delamination in polymer composites (Dry, 1996; Pang & Bond, 2005; Ramesh, Balaji, et al., 2022). A number of problems can occur as a result of these internal defects, such as macrocracks, moisture swelling, and de-bonding. These microcracks can also lead to deterioration in performance (Joseph et al., 2002; Ramesh, Rajeshkumar, Balaji, et al., 2022; Ramesh, Rajeshkumar, Sasikala, et al., 2022) and reduced bond strength, which can lead to de-bonding (Awaja, Gilbert, et al., 2009). Chain scission along with structural break-up causes the majority of surface damage to polymer structures and laminating polymers.

Damage to the physical properties of the damaged area occurs quickly, and this can spread locally or make its way to other locations. Repairing damaged chains can often restore their original properties and stop the damage from getting worse. Pressure, heat, light (which would include UV), impact, radiation, and high-energy particles damage polymer chains when they are exposed to external stressors. A dent, a crack, a microcrack, a rupture, or a fracture may be the result of the damage. Polymers and polymer composites used in industrial applications are protected from damage by adding damage-retardant and damage-resistant additives. In contrast, such additives also have no repairing methodologies once the seriously harmful stress overtakes the shield barrier (Blaiszik et al., 2010; Deepa et al., 2021; Feldman, 2002; Ramesh et al., 2021a). The ultimate molecular structure of thermosetting polymers is determined by the curing experimental parameters during manufacturing. Since curing reactions can be monitored, further influence on the end product’s specifications, including crack and microcrack formation, can be gained (Awaja et al., 2008; Awaja, Riessen, et al., 2009; Rajeshkumar, 2021). In recent times, self-healing or self-repairing polymer composites based on the biological wound-healing processes have been introduced (Brown et al., 2005; Devarajan et al., 2021; Kessler et al., 2003; Pang & Bond, 2005; Ramesh, Rajeshkumar, Balaji, et al., 2021; Ramesh, Rajeshkumar, Bhuvaneswari, 2021).

Fiber-reinforced composite packed with dicyclopentadiene monomer stabilized with 100–200 ppm p-tert-butyl catechol in microcapsules over a mean diameter of 160 lm were healed at 80°C to achieve up to 80% restoration (Devarajan et al., 2021; Kessler et al., 2003). Because of the high cost of production and scarcity of basic process knowledge, self-healing polymer composites are currently in a precarious position. The above composites are more effective at preventing further damage than they are at healing existing damage. These materials are complicated to work with because of their poor mechanical properties as well as their inability to form large structures. New polymer resin composites with self-healing properties such as thixotropic and phenolic epoxies have the prospects to provide the necessary understanding and capital accumulation as well as industrial solution.

1.2 Repairable at ambient conditions

The extremely repressed dispersion of their own polymer chains makes the fabrication of repairable polymeric substances with elevated mechanical stiffness and strength an enormous challenge. Poly(acrylic acid) (PAA) and poly(allylamine hydrochloride) (PAH) composites were synthesized by precisely adjusting the electrostatic as well as H-bonding interactions among both PAA and PAH, resulting in associative phase separation and in situ nanostructure formation. An electrostatic arrangement of PAA along with PAH complexes and the H-bonded association of PAA along with PAH complexes occurred as nanospheres scattered uniformly in the continuous phase. The PAA along with PAH copolymer was given a double-cross-linked structure as a result of this structural feature, which allowed for considerable reinforcement of the material. They had tensile strengths as high as approximately 67 MPa and elastic modulus as strong as approximately 2.0 GPa for the PAA along with PAH composites. A liquid-like form of the PAA along with PAH structures could be used to repair/heal the PAA along with PAH composite under room conditions (25°C, 40% humidity) because of the complex’s reversible electrostatic interactions and H-bonds between PAA and PAH (i.e., coacervate). Using the ‘ability to heal’ strategy identified here, high-strength and tight supramolecular polymer materials can be repaired or healed with ease (Zhu, et al., 2020) (Fig. 1.1).

Figure 1.1 Stress versus strain for repaired composite (Zhu, et al., 2020).

1.3 Delamination injection repair

Repairing of damaged fiber-reinforced polymer (FRP) composite laminates using the resin injection repair method was discussed in many earlier studies. Low-energy impacts and manufacturing flaws can damage FRP composites despite their excellent mechanical properties, including delamination and interlaminar cracking. For industries such as automotive, wind energy, and aerospace where composite materials are increasingly being utilized, repair procedures must be both time- and cost-effective. Vacuum and pressure are used to inject a low-viscosity resin into the damaged areas of a laminated component, which then cures as it becomes a solid. Nondestructive methods for detecting damage, usage of low-viscosity resins, resin injection repair strategies, case studies, and the difficulties of implementing this repair technique are all discussed in this chapter (Omairey et al., 2022; Saravana Kumar et al., 2017).

1.4 Self-healing methods

Internal damage to advanced polymer composites, including cracks and microcracks, that develops over time and degrades the performance of the material is a major source of concern. Failure, as well as fracture, occurs earlier than expected because of this. Nowadays, smart techniques that detect and repair internal damage before it causes a final failure are being sought to extend the lifespan of enhanced composite materials. Here, self-healing is regarded as one of the most important characteristics for responsive systems to detect internal damage and repair it. Developing smart self-healing polymer composites with prospective application fields in aerospace, transportation, coating, electronics, and robotics is a new and exciting research field. First, the concepts, as well as techniques associated with self-healing in polymer composite materials are introduced and briefly discussed. Then, the chapter moves on to discuss some of the challenges and recent accomplishments in this field. Then, an evaluation of the latest advancement in linking these methodologies is presented. As a result of these systems' use in various industries, recent successes have been possible (Ramesh, Kumar, et al., 2020; Shojaei & Khasraghi, 2021).

1.5 Nanofiber healing

An erudite self-healing carbon fiber composite relying on core nanofiber for construction purposes has been introduced. Coaxial electrospinning was used to encapsulate the self-healing epoxy resin and curing agent in polyacrylonitrile to create two-component core–shell nanofibers. The mechanical force of the composites has been enhanced by altering the interlaminar dispersion of the core–shell nanofibers, which have been dispersed and seen between carbon fiber layers. It was found that the bending force might be enhanced by 5.96% through the bending test. Self-healing conditions have been calculated by trying to cure kinetic analysis and the bending test. After 1 hour of self-healing at 120°C, the results showed a healing efficiency of 110.12%. Scanning electron microscopy clearly showed the discharge of the self-healing agent (SHA) as well as it trying to fill microcracks. Core–shell nanofibers could indeed enhance the mechanical force of composites, extending their useful life and opening up new structural implementation possibilities (Felix Sahayaraj et al., 2021; Wang, Cai, et al., 2021) (Fig. 1.2).

Figure 1.2 Nanofiber healing method (Wang, Cai, et al., 2021).

By altering the interlaminar dispersion of core–shell nanofibers, researchers were able to improve the composite’s mechanical strength and increase its bending strength by 5.96%. The increased mechanical strength of composites will open up a wider range of structural applications on the assumption that self-healing can be achieved. Changes in self-healing temperature and time were used to determine the best conditions for self-healing. After 1 hour of self-healing at 120°C, the results showed a healing efficiency of 110.12%. Scanning electron microscopy clearly showed the discharge of the SHA as well as it trying to fill microcracks. A scanning electron microscope (SEM) test showed that nanofibers mentioned in this research can satisfactorily repair microcracks smaller than 20 m and probably partly repair microcracks larger than 48 m (Shojaei & Khasraghi, 2021).

1.6 Carbon nanotube composites

Carbon nanotube (CNTs) composite are being used as nanofillers during the production of nanocomposites as they possess outstanding mechanical, electrical, thermal, and self-mending properties while weighing minimally (Hassanzadeh-Aghdam & Ansari, 2019; Idumah, 2021; Joo et al., 2018; Ramesh, Rajeshkumar, Bhoopathi, 2021). CNTs are smart and multifunctional materials. In addition to their superior thermal and electrical characteristics, CNTs have excellent polymer compatibility, which make them suitable for the fabrication of self-mending polymer nanocomposites (PNCs). On the other hand, how parameters affecting the polymer matrix–CNT nanocomposite degree of interaction affect the self-healing morphology. A bioinspirational concept of self-mending is achieved as nature is made up of self-healing composites. Engineering fields such as aerospace, automobiles, sporting goods, electronics, and robotics have long had a fascination with materials that can repair themselves. As a result of these characteristics, the materials' shelf life can be extended and replacement costs reduced, all the while ensuring safety.

Cracks can form within the structure’s enclosure, causing structural polymer composites to degrade and be damaged. Electronic skin’s ability to self-heal is critical for the next generation of wearable technology. There is still a lot of work to be done in the field of manufacturing conductors with good mechanical properties combined with thermal sensitivity, adhesion, and injectability. Deformation sensing and self-healing behavior of CFPP/CNT nanocomposites were studied in relation to the conductivity of the network. CFPP/CNT nanocomposite damage sensitivities were improved by spraying CNT into the prepregs and monitoring the press parameters to increase through-thickness electrical conductivity. Repetitive three-point bending test results show an increase in electrical resistivity in the thickness direction and a high degree of self-mending efficiency (96.83%) during the fourth cycle of reproducible testing (Ramesh, Kumar, et al., 2020).

1.7 Shape memory

For this research, we used the COMSOL Multi-physics finite element program to achieve our goals. After only 1 second of insonation, simulations showed a temperature emergence of up to 5.6K in the implanted shape memory polymer (SMP) fiber of an 8 mm thick, 18 mm length model composite with a 5.8% volume fraction of SMP. The fiber–matrix interfaces were found to generate heat, but the successive temperature upsurge within the embedded fibers was accomplished mostly through traditional heating conduction out from high-temperature interfacial zones into the fibers themselves. The rise in temperature was examined in relation to specimen length, thickness, and fiber volume fraction. This research sheds light on how ultrasound can help SMP FRP matrix composites initiate self-healing (Hassanzadeh-Aghdam & Ansari, 2019).

1.8 Carbon fiber

Bis-maleimides (BMIs) have healing properties at the polymer level, and they are thermally reversible. The post-impact behavior of reference and modified carbon-fiber-reinforced polymers (CFRPs) with the stacking sequence 2S and related volume fractions of fibers were tested by compression tests and evaluated under low-velocity impact (LVI). After impact, C-scan inspections showed that all CFRPs had comparable damage resistance, and compression prior to LVI divulged no deterioration due to the incorporation of a SHA. After impact, all CFRPs’ compressive strength degrades as expected, according to the compression after impact (CAI) tests. Finally, the SHA has been able to completely rebuild the damaged area since healing activation, while the remaining compression properties were greatly enhanced (Kostopoulos et al., 2021) (Fig. 1.3).

Figure 1.3 Carbon fiber (Kostopoulos et al., 2021).

The incorporation of Diels-Alder (DA) -based SHAs into CFRPs was already done in a novel way. An electrospinning process was used to electrospray specific areas of the CFRP material throughout all of the carbon fiber layers with DA-based materials in their unreacted form (TF and BMI oligomers). It was possible to replace some of a host resin matrix upon curing using SEP while simultaneously cross-linking the composites without affecting their architecture because the SHA has been uniformly distributed (i.e. thickening effect). As a result, compression tests performed in the initial situation revealed comparable in-plane mechanical characteristics between the reference and modified CFRPs, and similar resistance to damage evolution following an LVI incident (primarily by delaminations). There are a number of advantages to using the current method, such as the fact that it does not negatively impact the mechanical characteristics, the architecture of the composites, and providing good hardness values especially in comparison to other methods. To sum up, the current method appears to be a promising one for upcoming composite structures (Kostopoulos et al., 2021).

1.9 Tufted composites

New FRP composites using adorn with a tuft shape memory alloy (SMA) fibers combine greater delamination opposition with crack-closure properties. Thin Ni–Ti alloy SMA tufts are heated to activate a characteristic that partly terminates the delamination after crack growth. When the SMA tufts have still not deformed beyond a shape memory strain limit, finite element (FE) analysis shows that comprehensive fracture closure occurs, because of their damage tolerance and ability to close delamination cracks. SMA-tufted composite materials present an exciting potential start for destruction acceptant composite material development (Ciampa et al., 2021; Ramesh, Balaji, et al., 2021; Wang, Yuan, et al., 2021). SMA filaments can be used to tuft fiber-polymer laminates with a high configuration I delamination opposition and the ability to close delamination cracks. The traditional tufting method can be used to insert SMA filaments through the width of dry fabric preforms. Because the SMA tufts created a large-scale bridging method region all along the delamination fracture, the tufted laminate had significantly enhanced configuration I interlaminar fracture toughness. Elastic deformation is accompanied by plastic deflection and pull-out in the SMA tufts, which create high bridging traction loads (Fig. 1.4).

Figure 1.4 Finite element model (Ciampa et al., 2021).

The delamination crack was partially closed (by 50%) using electrical resistance heating of the SMA tufts. Partial crack closure was achieved by driving closure forces into the first row of bridge tufts near crack’s tip, which generated the first traction load for closure. When heated, these tufts retained their original shape because they had not been elongated beyond the SMA’s shape memory limit. The tufts further toward the bridging zone, on the other hand, had been deformed beyond the point of repair. Heating did not activate the shape memory influence through these severely deformed tufts, so they were unable to aid in the fracture closure method. Once if the fracture opening is below a shape memory strain threshold, the SMA tufts can completely close the delamination (Ciampa et al., 2021).

1.10 Carbon composite

There were two different sorts of self-repairable composite laminates which are embedded with microcapsules of 6 and 12 wt.%, correspondingly. Using a piezoelectric transducer and a pitch-catch approach, we activated and captured the guided waves. Mode Double cantilever beam samples were used for interlaminar fracture tests, and the effects of microcapsule concentration on specimen interlaminar properties were investigated. When analyzing mechanical tests and guided wave detecting findings, interlaminar crack areas of self-healing samples have been observed. High-concentration microcapsule specimens have a lower self-healing efficiency than samples with low-concentration microcapsules. The specimens’ interlaminar properties are decreased by low-concentration microcapsules. The self-healing ability of specimens was found to be correlated with two guided-wave parameters: signal peak value and waveform similarity. Responding signals have lower peak values and larger waveform differences when specimens have been damaged. A rise in response signal amplitude and a smaller waveform distinction were seen between healed specimens (Loh et al., 2021).

The potential of carbon fiber/epoxy (CF/EP) composite materials to fully integrate microcapsules to self-heal using an ultrasonic guided wave is being evaluated using a simple but reliable preliminary technique. With a low-profile piezoelectric transducer fixed to the surface, an experimental pitch-catch-directed wave-promulgating arrangement has been tested on double cantilever beams. To evaluate the interlaminar characteristics of CF/EP composites, the ultrasonic guided wave method can be used to analyze the changing trend of communications peak value and waveform resemblance with the progression of interlaminar damage in self-healing specimens, according to the results. High-concentration samples have a lower recovery efficiency for interlaminar characteristics than low-concentration specimens. High-concentration microcapsules, on the other hand, improve interlaminar characteristics of specimens due to the amalgamation influence of microcapsules. Nondestructive testing technique for assessing the self-healing abilities of CF/EP composites could be developed using the guided-wave-based technique. This could lead to the technological applications of self-healing composites. Numerous different specifications of ultrasonic guided waves, including local wave numbers, frequency-domain analyses, and time-frequency analyses, will be examined in upcoming work in order to improve the suggested technique and quantitatively estimate the effect of self-healing (Loh et al., 2021; Ramesh, Rajeshkumar, Bhoopathi,