**1. Introduction**

Textiles are versatile materials composed of natural or synthetic fibers, with a wide range of applications [1,2]. With the global economy and technological advancements, smart textiles [3–5] are one of the research hotspots in the field of textiles and garments. Intelligent textiles are a sort of smart fabric or material which can be responsive to the external environment or an outside stimulus in behavior, including electrical, chemical, biological agents or physical temperature [6,7]. Currently, in order to introduce some kind of advanced function or special performance, smart textile materials are often modified by direct coating technology such as roll coating, the spraying method or deposition and surface treatment approaches, such as plasma treatment technology, ultraviolet irradiation [8], etc. These technologies are very useful and applied for smart textiles in improving or introducing some kind of certain performance based on the concrete requirements in actual applications. However, it should be mentioned that the utilization of traditional coating technology often inevitably hides the original capabilities of fabrics. Additionally, surface process techniques often concern a complicated process or environmental pollution along with surface structure destruction. This inevitably leads to the degeneration of some other characteristics of fabrics, such as tenderness, breathability and hygroscopicity.

 Li, J.; Wang, B.-X.; Cheng, D.-H.; Liu, Z.-M.; Lv, L.-H.; Guo, J.; Lu, Y.-H. Electrospun Sericin/PNIPAM-Based Nano-Modified Cotton Fabric with Multi-Function Responsiveness. *Coatings* **2021**, *11*, 632. https:// doi.org/10.3390/coatings11060632

**Citation:**

Academic Editor: Esther Rebollar

Received: 23 March 2021 Accepted: 12 May 2021 Published: 25 May 2021

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As a comparison, electrospinning technology [9] has shown enormous potential such as filtration, separation [10,11], drug delivery of biomedical materials [12,13] and intelligent fabric modification because of grea<sup>t</sup> advantages such as the smaller fiber diameter, the higher porosity and permeability rate, large specific surface area, and high mechanical capacity [14,15], as well as its effective approaches of synergizing the required functions of materials and outstanding performance of textiles. However, the fabrics of intelligent modification with electrospinning technology are generally e-textiles and pressure-sensitive fabrics [16,17]. Furthermore, the fabrics of intelligent modification with electrospinning technology are generally e-textiles [18] and pressure-sensitive fabrics [19]. Though coupling electrospinning technology to thermo-responsive polymers such as poly(N-isopropylacrylamide) can effectively produce smart responsive nanofibers [20–23], few studies use them to modify textiles. In addition, most thermoresponsive textiles are conducted by coating smart polymers in industrial technologies. Currently, the coating smart polymers are mainly prepared and applied in the form of threedimensional hydrogels with the shortcoming of smaller poriness and lower surface area and response rate.

In our previous work [24], multifunctional mulberry silk fabrics were successfully prepared with PNIPAM/chitosan/PEO nanofibers. The modified mulberry silk fabrics represented brilliant temperature- and pH-susceptivity and antibacterial capabilities. This prompted us to investigate other fabric applications such as cotton fabrics. Based on this, we chose the sericin of the Antheraea pernyi silks as the main raw materials. This took full advantage and improved the application of Antheraea pernyi silk sericin.

Here, we present a strategy for the fabrics, which brings some new ideas of modified fabrics. First, we prepared a kind of thermo-responsive polymer hydrogel by blending sericin/PEO solutions with N-isopropylacrylamide using an interpenetrating polymer network technology. Second, we prepared thermo-responsive nanofiber materials through electrospinning technology. Third, the modified cotton textiles that possessed temperatureand pH-sensitivity were produced by using the nanofiber network. The properties of the smart textiles were investigated and contrasted with those of the other samples. In addition, the biological property of smart textiles was examined with an antimicrobial activity test. This study suggests the potential of the temperature- and pH-responsive smart textiles to tissue engineer support materials, medicine slow release materials and other responsive materials.

#### **2. Experimental Procedure**
