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Polymeric Biomaterials and Current Trends for Advanced Applications
Published in Anandhan Srinivasan, Selvakumar Murugesan, Arunjunai Raj Mahendran, Progress in Polymer Research for Biomedical, Energy and Specialty Applications, 2023
Vineeth M. Vijayan, Suja Mathai, Vinoy Thomas
Shape memory polymers (which have the capability to return from a deformed shape to their original state under the assistance of an external stimulus like temperature) are widely utilized for 4D bioprinting applications as they have the temperature-controlled shape changes.104,105 Currently most of the shape memory polymers are having high shape transition temperature which makes it more inconvenient for biomedical implantations. This has led towards the quest of new shape memory polymers whose transition temperature lies in the room temperature range. In this regard, Zhang et al. have reported a new shape memory polymer named poly (glycerol dodecanoate) acrylate (PGDA) (Figure 2.11).106 This new polymer was synthesized by the polycondensation of glycerol and dodecanedioic acid. This prepared PGDA polymer has shape transition temperature around 20–37°C, which lies in the room temperature range. This low shape transition temperature range makes it ideal for biological applications. This new polymer was utilized to fabricate different structures such as triangular star, six-petal flower, and honeycomb. These 3D structures have shown high shape fixity and recovery ratios. The biomedical use of this shape memory polymer was demonstrated by showing its utility as a stent and vascular graft.
Waterborne Polyurethanes for Automobile Industries
Published in Ram K. Gupta, Ajay Kumar Mishra, Eco-Friendly Waterborne Polyurethanes, 2022
Shape memory polymers are an emergent section of advanced smart materials [52]. Shape memory polymers possess the ability to demonstrate shape memory upshot [53]. Characteristically, shape memory polymers may display shape alteration upon suitable stimulus, such as heat, light, electric current, voltage, stress, pH, water, and other environmental effects. An imperative feature is use of an appropriate type of polymer. Generally, segmented polymers are preferred, including polyurethanes, polyesters, epoxies, etc., and other segmented polymers. Such segmented polymers generally can mimic shapes under the effect of some external force, as mentioned earlier [54]. The automobile industry is shifting from the use of solvent-borne polyurethane to waterborne polyurethane technology. Shape memory waterborne polyurethanes have been found to be beneficial in various car parts and internal components. The use of shape memory waterborne polyurethanes not only reduces the overall weight of the car compared to the metal body but also prevents problems, such as external metal damage by corrosion or denting.
Potential application of high-performance polymers in the oil and gas drilling engineering
Published in Domenico Lombardo, Ke Wang, Advances in Materials Science and Engineering, 2021
Shape memory polymer material is a kind of smart material that can change shapes under external environmental stimuli. The deformable structure of this smart material has shown great application potential in many fields such as biomedicine, aerospace, etc., and it can be used as plugging device, bracket device, and releasing devices 4D printed shape memory polymers can form relatively complex, personalized, and high-precision structures, or structures that are difficult to achieve with traditional preparation techniques. It may provide new ideas for intelligent control and controllable plugging in the oil and gas field [8–11].
Exact solution for dynamic analysis of a shape memory polymer plate subjected to the initial conditions
Published in Mechanics Based Design of Structures and Machines, 2023
Shape-memory polymers are a type of viscoelastic material that has the ability to change geometry-shape in response to temperature, light-induced, and electro-active (Margoy et al. 2021). Huang et al. (2020) studied the recent advances and new developments of SMPs. According to this investigation, over the last two decades, SMPs have attracted immense interest and have been studied intensively worldwide. According to this investigation, it was observed that there are three different models to simulate the SMPs as follows; Rheological models of SMPs.Phase transition models of SMPs.Models combining viscoelasticity and phase transitions.
Design of 4D printed shape-changing tracheal stent and remote controlling actuation
Published in International Journal of Smart and Nano Materials, 2021
Fenghua Zhang, Nan Wen, Linlin Wang, Yunqi Bai, Jinsong Leng
Shape memory polymers (SMPs) and their composites (SMPCs) can recover from the preset temporary shape to the initial shape under the external stimuli including heat, light, electricity and magnetism. Due to the advantages of large deformation and strong recovery ability, SMPs and SMPCs have attracted much attention in biomedicine, aerospace, flexible electronics and other fields. Polylactic acid (PLA) with good biocompatibility has been widely used in biomedical field [1–4]. The shape memory epoxy-acrylate hybrid photopolymer was synthesized by Yu [5], and the complex structure was prepared by stereolithography. Sonawane, V.C [6]. et al. prepared tacrolimus-eluting scaffolds with shape memory PLA and poly-L-glycolic acid (PLGA) by solvent casting. The mixed hydroxyapatite of PLA was used to repair the bone defect. However, the traditional manufacturing process cannot provide accurate complex structures for SMPs, and it is difficult to further meet the requirements of high-tech fields such as minimally invasive medicine and precision medicine for the complexity of smart structures.
Investigation of the shape memory and actuation properties of different asymmetric smart polymer composites
Published in Advanced Composite Materials, 2021
Abdul Basit, Gildas Lhostis, Bernard Durand
The shape memory properties of shape memory polymers and their composites strongly depend on their constitution as it changes the rigidity and stiffness of the composite. In general, SMPs have low strength and stiffness that is why they have high elongation strain. The addition of reinforcement such as carbon nano-tubes, nano-fibers, fillers, fibers or fabric layers, etc., increases the stiffness and strength of the structure which ultimately influence the shape memory properties of the shape memory polymer composites. The increase in stiffness due to the reinforcement increases the elastic modulus of the structure. Hence, the instantaneous spring-back displacement increases during the programming cycle of the composite which results in a decrease in overall fixity of the composite [9].