Shape memory polymer composite coatings with enhanced mechanical and antimicrobial properties

Abstract

Purpose This paper aims to exploit shape memory polymer (SMP) composite as multifunctional coatings for protecting substrates from surface wear and bacterial. The efficiency of added nano or micro-sized particles in enhancing the properties of SMP was investigated. This study also attempts to use a low-cost and effective spraying approach to fabricate the coatings. The coatings are expected to have good conformability with the substrate and deliver multi-functional performance, such as wrinkle free, wear resistance, thermal stability and antimicrobial property. Design/methodology/approach High-performance SMP composite coatings or thin films were fabricated by a home-made continuous spray-deposition system. The morphologies of the coatings were studied using the scanning electron microscope and the transmission electron microscope. The abrasion properties were evaluated by Taber Abraser test, and thermo-gravimetric analysis was carried out to investigate the thermal properties of prepared composites. The antimicrobial property was determined by the inhibition zone method using E. coli. The thermally responsive shape memory effect of the resulting composites was also characterized. Findings The morphology analysis indicated that the nanoclay was distributed on the surface of the coating which resulted in a significant improvement of the wear property. The wear resistance of the coatings with nanoclay was improved as much as 40 per cent compared with that of the control sample. The thermo-gravimetric analysis revealed that the weight loss rate of composites with nanoclay was dropped over 40 per cent. The SMP coating with zinc oxide (ZnO) showed excellent antimicrobial effect. The shape recovery effect of SMP/nanoclay and SMP/ZnO composites can be triggered by external heating and the composites can reach a full shape recovery within 60 s. Research limitations/implications This study proposed a continuous spray-deposition fabrication of SMP composite coatings, which provides a new avenue to prepare novel multi-functional coatings with low cost. Originality/value Most studies have emphasized on the sole property of SMP composites. Herein, a novel SMP composite coating which could deliver multi-functionality such as wrinkle free, wear resistance, thermal stability and antimicrobial property was proposed.

Highly Stretchable and Wearable Strain Sensor Based on Printable Carbon Nanotube Layers/Polydimethylsiloxane Composites with Adjustable Sensitivity

“…The pattern design of sensors was done in a CAD software. Printer setup and printing parameters could be found in our previous study. , Specimens were printed at the speed of 15 mm/s, and during the printing process, PDMS substrates were placed on a heating platen with a temperature of 90 °C to induce the water evaporation. After the printing process, copper wires were attached to the end of CNT patterns and finally another layer of PDMS was cured on top of printed patterns to obtain the composite strain sensors.…”

Effect of GNPs and resin blend on tear resistance of 4D printed shape memory photopolymer composite

“…When compared with other 3 D printing technologies, the digital light processing (DLP)-based resin 3 D printing (R3DP) technique creates objects using localized photopolymerization and can produce items with very complicated geometries and high resolution (Kuang, 2021). This raises a huge interest among the researchers on photopolymer (PP) resin printing technology using DLP due to its applicability to a variety of applications ranging from automotive to aerospace (Pei, 2014), biomedical devices to drug delivery systems (Wang et al , 2018), smart electronic devices to soft robotics (Yap et al , 2020) and shape-changing cloths to smart textiles (Andreu et al , 2021). Figure 1 depicts the working of liquid crystal display (LCD)-type R3DP apparatus used to fabricate SMPPCs specimens.…”