The Application of Shape Memory Polymer (SMP) in Textiles

The Application of Shape Memory Polymer (SMP) in Textiles

Noor Ahmed Raaz
Specialized in Apparel Manufacturing
Owner and Editor in chief Textile Merchandising
Asst. Prof., Department of Textile Engineering
Atish Dipankar University of Science & Technology
Email: mnnabi@adust.edu.bd

 

Shape Memory Polymer:

Shape-memory polymers are a developing class of dynamic polymers that have dual-shape skills. They can change their shape in a predefined way from the shape it consists to the shape as exposed to an appropriate stimulus. While the shape under stimulus is given by the initial processing step, the initial shape is determined by applying a process called programming. This concept has been extended to other stimuli by either indirect thermal actuation or direct actuation by addressing stimuli-sensitive groups on the molecular level. Finally, polymers are introduced that can be multifunctional. Potential applications for such materials as active medical devices are highlighted. In this paper, the application of shape memory polymer in the textile are discussed along with the opportunities and challenges.

Application of SMP in Textiles:

There are lots of applications of shape memories polymer in textiles. Here I discuss a few major applications such as follows-

1. Smart Energy Storage Textiles
2. Deodorant Fabrics
3. Wound-dressing Products
4. Damping Fabrics
5. Breathable Fabrics
6. Fabric Finishing
7. Ergonomic Textile

1. Smart Energy Storage Textiles:

Wearable electronics carve a distinct niche in our daily lives by providing changes in outdated living habits to less consuming and healthier ones. Electronic circuits are generally integrated into flexible textile matrices to achieve such smart wearable electronics. Batteries and supercapacitors are two archetypal energy storage devices, which is extensively used in our daily life. The capability of storing energy strongly relies on the properties of electrodes, including microarchitecture, conductivity, and specific surface area. SMPs in a SC usually serve as the substrate or core, with a conducting layer and an active layer attached successively to the surface of the shape-memory substrate or core to make a shape-memory electrode. Huang et al. used shape memory material as the fiber core, which was consecutively coated with MnO2 and PPy to fabricate temperature-sensitive electrodes.

2. Deodorant Fabrics:

Such special fabrics have the ability to release deodorant agents at certain temperatures. The smart fabric is fabricated by coating a stimuli-responsive polymeric hydrogel on the textile surface. The hydrogel is attached to the textile surface through chemically cross-linking by using a functional monomer, such as acrylamide, and a cross-linking agent such as 2-(diethylamino) ethyl acrylate. Deodorant is generally incorporated into the hydrogel during or after the cross-linking reaction. Usually, β-cyclodextrin is loaded with polymeric gel for further enhancing the controlled release properties of hydrogel-modified textiles. β-cyclodextrin has a hydrophobic interior cavity and a hydrophilic external surface in its structure. Therefore, different types of hydrophobic guest deodorant moieties can be included in its cavity. Recently, a few body-responsive deodorant hydrogel products are also available on the market. Even though such advantages of deodorant fabrics, it is not fully explored. A few issues such as soft handles and high stability of the products need to be taken into consideration for the development of such fabric. Another important factor is controlling the hydration degree of the product in the open environment.

3. Wound-dressing Products:

Chitin and chitosan derivatives are extensively used to fabricate wound dressing products due to their better antibacterial properties and wound-healing properties. Chitosan hydrogel as a wound dressing material can help in the reestablishing of skin architecture. Chitosan-treated alginate filaments and cotton fabric have been fabricated for advanced wound dressings. In addition to chitin/chitosan, various biopolymer-based hydrogel products have also been developed for wound dressing. Such smart wound dressing materials can deliver a novel drug release system in response to variations in pH/temperature; thus, the wounds can quickly heal.

4. Damping Fabrics:

SMPs can absorb effect energy due to their better damping properties at around Tg. Allied Signal Inc. manufactured an automotive seatbelt fabric using SMP fibers (Securus fibers) which can absorb the kinetic energy and so effectively rise a passenger’s safety by utilizing the damping effect of the SMPs. The Securus fibers are prepared of shape memory poly (ethylene terephthalate)-poly (caprolactone) block copolymers. It is reported that the fiber can absorb energy from the body’s forward motion and thus improves the safety of passengers during an accident.

5. Breathable Fabrics:

SMPUs are used for fabrication of breathable fabrics. WVP of the SMPU can be simply altered rendering to the wearer’s body temperature. The total WVP of SMPU films can be enhanced by including hydrophilic segments such as dimethylpropionic acid and diol-terminated poly (ethylene oxide) in SMPUs. The total WVP of SMPs can also be meaningfully improved by forming micro foams in the SMPUs.

6. Fabric Finishing:

Thermo-responsive SMPs can be useful in the textile via apparel finishing. Wrinkle-free, crease retention, anti-shrinkage and dynamic visual textiles are fabricated by giving SMPs on fabrics. An investigation on it originate that the cotton fabrics treated with SMP show better wrinkle-free effect. Cotton fabric apply with SMPU can recover to its original flat shape (wrinkle-free) within a minute upon blowing steam over it. SMP-treated fabrics keep good crease and pattern retention ability. As a result, good aesthetic appeal is reached in such treated fabric.

7. Ergonomic Textile:

The violin is made from a combination of shape memory polymer and carbon fibers. The shape memory polymer used here is “Veriflex”. Itdesigned to help to reduce the neck and shoulder pain of the player, as it can be reshaped as desired by the player.