sign in sign up
<<
Home , Hand feel, Spandex

Communication Study on the Development of Antiviral Spandex Fabric Coated with Poly(Hexamethylene Biguanide) Hydrochloride (PHMB)

Wen-Yi Wang 1, Sui-Lung Yim 2, Chun-Ho Wong 2 and Chi-Wai Kan 1,*

1 Institute of and , The Hong Kong Polytechnic University, Hong Kong 999077, China; [email protected] 2 Avalon SteriTech Limited, Shatin, New Territories, Hong Kong 999077, China; [email protected] (S.-L.Y.); [email protected] (C.-H.W.) * Correspondence: [email protected]; Tel.: +852-2766-6531

Abstract: The spread of COVID-19 has brought about huge losses around the world. This study aims to investigate the applicability of PHMB used for developing antiviral spandex clothing against coronavirus. PHMB was qualitatively determined on the surface of spandex fabrics by using BPB. The antiviral analysis shows that the PHMB-treated spandex fabric can kill 99% of the coronavirus within 2 h of contact, which suggests that the spandex fabric treated with PHMB could be used for developing antiviral clothing against coronaviruses for containing the transmission of COVID-19 in high-risk places. Furthermore, PHMB-treated spandex fabrics were shown excellent antibacterial activity against gram-positive S. aureus and gram-negative K. pneumoniae. The hand feel properties of Spandex fabric were not significantly affected by the PHMB coating in addition to the wrinkle  recovery, which was obviously improved after PHMB coating. 

Citation: Wang, W.-Y.; Yim, S.-L.; Keywords: PHMB; antiviral clothing; coronavirus; protective spandex clothing Wong, C.-H.; Kan, C.-W. Study on the Development of Antiviral Spandex Fabric Coated with Poly(Hexamethylene Biguanide) 1. Introduction Hydrochloride (PHMB). Polymers Spandex fiber is a long-chain synthetic polymeric fiber which was first invented at 2021, 13, 2122. https://doi.org/ DuPont’s laboratory in 1959 [1]. It is reported that spandex fabric can be stretched up to 10.3390/polym13132122 five to eight times its normal size and then recover to its original shape [2]. Spandex fabric (Lycra®, spandex, and elastane are mostly synonyms) is gaining popularity in making Academic Editor: Fabien Salaün stretchable clothing in recent years due to its extraordinary merits such as exceptional elasticity, durability, and light weight [3]. In addition to this, spandex fabric is supple and Received: 8 June 2021 more adaptable, which makes spandex widely used in garments where both and Accepted: 25 June 2021 Published: 28 June 2021 fit are required such as , , exercise wear, surgical hose, , gloves, , wrestling suits, and rowing suits [4–6]. There are four methods available for fabricating spandex fibers, i.e., melt extrusion, Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in reaction , solution dry spinning, and solution wet spinning, among which solution published maps and institutional affil- dry spinning is the most used method for fabricating spandex, with nearly 95 percent of the iations. world’s spandex being manufactured by this method [2]. Briefly, the first step included in this method is the production of a prepolymer by mixing macroglycol (, polyether, polycarbonate, polycaprolactone, or a combination of these chemicals) with a diisocyanate . The prepolymer is then reacted with diamine acid to extend the chain of the prepolymer. Afterwards, this solution is diluted to make it easier to handle before Copyright: © 2021 by the authors. extrusion [7]. Through heating, twisting, finishing, and , the elastic and durable Licensee MDPI, Basel, Switzerland. This article is an open access article spandex fabrics are finally produced. The stretching characteristic of spandex is ascribed to distributed under the terms and the hydroxyl groups on both ends of the macroglycol, while the strength results from the conditions of the Creative Commons shorter chain group [1]. Though spandex fabric has lots of advantages Attribution (CC BY) license (https:// as mentioned above, it also suffers from some disadvantages with its poor breathability and creativecommons.org/licenses/by/ hygroscopicity. These problems can be addressed by blending or other breathable 4.0/). materials with spandex [8].

Polymers 2021, 13, 2122. https://doi.org/10.3390/polym13132122 https://www.mdpi.com/journal/polymers Polymers 2021, 13, 2122 2 of 7

Polymers 2021, 13, 2122 2 of 7 breathability and hygroscopicity. These problems can be addressed by blending cotton or other breathable materials with spandex [8]. play a significant role in the transmission of infectious diseases because of theTextile vulnerability fibers play to microbial a significant attack. role The in the outbreak transmission of COVID-19 of infectious around diseases the world because has goneof the on vulnerability for one and to a microbialhalf years attack. and has The alread outbreaky resulted of COVID-19 in huge aroundlosses [9]. the It world has been has reportedgone on forthat one COVID-19 and a half could years survive andhas for 48 already h on cloth resulted [10], inwhich huge makes losses it [ 9indispensable]. It has been toreported develop that antiviral COVID-19 fabrics could with survive potential for 48 application h on cloth in [10 protective], which makes clothing. it indispensable In order to achieveto develop antiviral antiviral activity, fabrics a wide with variety potential of ch applicationemicals have in protectivebeen applied clothing. to textile In products order to suchachieve as antiviraltriclosan activity,via a wide technology variety of chemicals[11]. Apart have from been the applied broad-spectrum to textile products bacteri- such as triclosan via finishing technology [11]. Apart from the broad-spectrum bactericidal cidal properties, one of the major problems for these treated antiviral fabrics is the dura- properties, one of the major problems for these treated antiviral fabrics is the durability bility against wear and household washing. against wear and household washing. Poly(hexamethylene biguanide) hydrochloride (PHMB) is a well-known commercial Poly(hexamethylene biguanide) hydrochloride (PHMB) is a well-known commercial bactericide that has been widely used in a variety of areas such as the food industry and bactericide that has been widely used in a variety of areas such as the food industry and recreational water because of its low toxicity and broad-spectrum bactericidal properties recreational water because of its low toxicity and broad-spectrum bactericidal proper- [12,13]. PHMB is composed of repeating biguanidine units spaced by hydrophobic hexa- ties [12,13]. PHMB is composed of repeating biguanidine units spaced by hydrophobic methylen hydrocarbon chains (Figure 1). The antibacterial mechanism of PHMB is highly hexamethylen hydrocarbon chains (Figure1). The antibacterial mechanism of PHMB dependent on the cationic biguanide moieties that can interact with the negatively is highly dependent on the cationic biguanide moieties that can interact with the nega- charged phosphate head groups of bacterial cell membrane and finally cause cell death tively charged phosphate head groups of bacterial cell membrane and finally cause cell [14,15]. In the , PHMB is generally used through the processes of padding, death [14,15]. In the textile industry, PHMB is generally used through the processes of spraying,padding, conventional spraying, conventional exhaust method exhaust or pa methodd–dry–cure or pad–dry–cure [16]. PHMB [shows16]. PHMB strong shows affin- itystrong to cellulosic affinity to fibers cellulosic due fibersto electrostatic due to electrostatic interaction interaction and hydrogen and hydrogen bonding bonding and the andad- sorptionthe adsorption follows follows typical typical Langmuir Langmuir isotherms isotherms at lower at lower concentrations concentrations [13]. [Therefore,13]. Therefore, the fabricsthe fabrics treated treated with withPHMB PHMB display display excellent excellent durability durability against against household household laundering launder- [17]. Moreover,ing [17]. Moreover, PHMB has PHMB modest has virucidal modest virucidal activity against activity non-enveloped against non-enveloped viruses such viruses as HIV-1such as [18]. HIV-1 The [ 18mechanism]. The mechanism of action of of action PHMB-bas of PHMB-baseded biocides biocidesis to interact is to with interact the withviral capsidthe viral and capsid to lead and to to virus lead death to virus [19]. death Hence, [19]. the Hence, present the study present aims study to develop aims to developan anti- viralan antiviral fabric against fabric against COVID-19 COVID-19 with potential with potential application application for protective for protective clothing clothing by using by PHMB.using PHMB.

Figure 1. ChemicalChemical structure structure of PHMB.

2. Materials Materials and and Methods Methods 2 Spandex- (cotton(cotton 92%/spandex92%/spandex 8%) withwith weightweight 180180 g/cmg/cm2 waswas used in thisthis study. Poly(hexamethylene biguanide)biguanide) hydrochloridehydrochloride (PHMB)(PHMB) asas aa 20%20%w w/v/v aqueous solution,solution, PEG400 (400 g/mol in in average), average), polyurethane binder (20% ww/v/v aqueousaqueous solution), solution), and bromophenol blue (BPB) sodium were suppliedsupplied by Sigma-Aldrich (St. Louis, MO, USA). 2.1. PHMB Coating Treatment 2.1. PHMB Coating Treatment The finishing recipe was prepared by adding 10% (w/v) PHMB, 5% (w/v) PEG400, The finishing recipe was prepared by adding 10% (w/v) PHMB, 5% (w/v) PEG400, and and 8% (w/v) binder into deionized water. The process of pad–dry–cure was used to treat 8%the ( fabricw/v) binder samples. into The deionized fabric sample water. was The firstly proces paddeds of pad–dry–cure with the finishing was used solution to treat with the a fabricwet pickup samples. of 80%. The Afterwards,fabric sample the was sample firstly was padded dried with in an the oven finishing at 90 ◦ Csolution for 5 min with and a wetthen pickup cured atof 13080%.◦C Afterwards, for 45 s. the sample was dried in an oven at 90 °C for 5 min and then cured at 130 °C for 45 s. 2.2. Qualitative Analysis of PHMB 2.2. QualitativeThe presence Analysis of PHMB of PHMB on the fabric was qualitatively determined by the anionic dye BPB,The which presence can be of complexed PHMB on with the fabric PHMB was with qu thealitatively formation determined of a blue stable by the complex anionic [dye16]. BPB,The present which studycan be utilizes complexed BPB towith qualitatively PHMB with determine the formation the presence of a blue of PHMB stable coated complex on the fabrics.

Polymers 2021, 13, 2122 3 of 7

2.3. Antiviral Activity The antiviral activity of the fabric samples treated with PHMB was tested in accordance with ISO 18184:2019. The antiviral fabrics (20 × 20 mm) were inoculated with 200 µL of virus at a concentration of 105 and left for 2 h at 25 ◦C. After contacting for 2 h, 20 mL of wash-out solution in the vial containers was added with agitation by Vortex mixer for 5 s and 5 times to wash out the virus from the specimens. TCID50 (Median Tissue Culture Infectious Dose) was calculated following the appropriate incubation time. The antiviral activity value was then calculated by comparison of the antiviral test recover from the control fabric according to Equation (1) as follows:

M = lg(Va) − lg(Vb) (1)

where M is the antiviral activity value, lg(Va) is the common logarithm average infectivity titer after 2 h of contact (PFU/vial) with the reference specimen, and lg(Vb) is the common logarithm average infectivity titer after 2 h of contact with the antiviral spandex fabric.

2.4. Antibacterial Property The antibacterial property of treated samples was qualitatively investigated against gram-positive S. aureus and gram-negative K. pneumoniae according to AATCC TM 147-2011, and the quantitative determination was performed in accordance with AATCC TM100-2019. The bacteria were grown in nutrient agar at 37 ± 2 ◦C for 24 h. Fabric samples were cut into 20 × 20 mm pieces for the antibacterial test. The zone of inhibition around the samples were photographed at the end of the incubation period. The average width of inhibition zone along a streak on either side of the sample was calculated by Equation (2) as follows:

W = (T − D)/2 (2)

where W = width of clear zone of inhibition in mm; T = total diameter of test specimen and clear zone in mm; and D = diameter of the test specimen in mm. The Inhibition percentage of PHMB-coated spandex samples were calculated as per Equation (3):

Inhibition % = [(A − B)/A] × 100% (3)

where A = CFU/mL for sample at 0 h and B = CFU/mL for sample after 24 h.

2.5. Hand Feel Evaluation The hand feel properties of Spandex after PHMB coating, i.e., resilience, softness, smoothness, and wrinkle recovery, were evaluated by using a PhabrOmeter instrument (Nu Cybertec, Inc., Davis, CA, USA) according to AATCC Test Method 202-2014.

3. Results and Discussion 3.1. Qualitative Analysis of PHMB Coated on the Surface of Spandex Fabric Spandex fabric is distinguished for its remarkable elasticity, which is desired in many applications such as form-fitting garments, , and glove fabric. The present study aims to impart spandex fabric with antiviral activity against coronavirus by using PHMB. Figure2 demonstrates that the spandex fabric treated with PHMB shows a distinct blue shade, as compared to the control sample, which suggests the presence of the PHMB coating on the surface of the spandex fabric sample. PolymersPolymers2021 2021, ,13 13,, 2122 2122 44 of 77

FigureFigure 2.2. ImagesImages ofof thethe untreateduntreated fabricfabric andand PHMBPHMB treatedtreated fabricfabric sample.sample.

3.2.3.2. AntiviralAntiviral ActivityActivity ofof PHMBPHMB CoatedCoated SpandexSpandex FabricFabric Then,Then, thethe antiviralantiviral activityactivity of of the the PHMB-treated PHMB-treated spandex spandex fabric fabric against against Feline Feline coron- coro- avirus,navirus, a surrogatea surrogate virus virus of SARS-CoV-2, of SARS-CoV-2, was studiedwas studied and shown and shown in Table in1 Table. It can 1. be It clearly can be observedclearly observed that the PHMB-treatedthat the PHMB-treated spandex fabric spandex had strong fabric antiviral had strong behavior antiviral against behavior Feline coronavirusagainst Feline after coronavirus 2 h of contact, after with2 h of up contact, to 99% with viral up inactivation. to 99% viral The inactivation. antiviral activityThe an- valuetiviral is activity 2.21. SARS-CoV-2 value is 2.21. can SARS-CoV-2 survive for 48can h onsurvive cloth for according 48 h on to cloth report according [9]. This to demon- report strates[9]. This that demonstrates the PHMB-treated that the spandex PHMB-treated fabrics could spandex effectively fabrics contain could theeffectively transmission contain of coronavirus.the transmission The actionof coronavirus. mechanism The could action be mechanism due to the interaction could be due of PHMB to the withinteraction the viral of capsid,PHMB leadingwith the to viral virus capsid, death [leading19]. Considering to virus death the susceptibility [19]. Considering of COVID-19 the susceptibility to standard of disinfectionCOVID-19 to methods standard [9 ],disinfection it is believed methods that PHMB-treated [9], it is believed spandex that fabricsPHMB-treated could play spandex a role infabrics containing could theplay transmission a role in containing of COVID-19, the transmission particularly of inCOVID-19, high-risk places.particularly in high- risk places. Table 1. Antiviral activity values of the control and PHMB treated fabric samples. Table 1. Antiviral activity values of the control and PHMB treated fabric samples. Logarithm Average of Infectivity Antiviral Sample Percentage/% LogarithmTiter Average (PFU/vial) of Infectivity Activity Sample Antiviral Activity Percentage/% ImmediatelyTiter after (PFU/vial) 5.71 N/A N/A Control Immediatelyinoculation after inoculation 5.71 N/A N/A Control AfterAfter contacting contacting for 2 for h 2 h 5.24 5.24 0.47 0.47 66.29 66.29 PHMB-treatedPHMB-treated span- AfterAfter contacting contacting for 2 for h 2 h 3.50 3.50 2.21 2.21 99.38 99.38 spandexdex fabric fabric

3.3.3.3. AntibacterialAntibacterial PropertiesProperties ofof PHMB-CoatedPHMB-Coated SpandexSpandex FabricFabric Next,Next, thethe antibacterial antibacterial activity activity of of spandex spandex fabrics fabrics after after PHMB PHMB treatment treatment was was evaluated evalu- bothated qualitativelyboth qualitatively and quantitatively. and quantitatively. Figure Figure3 displays 3 displays the images the images of control of control sample sample and PHMBand PHMB treated treated spandex spandex fabric infabric the inhibition in the inhibition of S. aureus of S.and aureusK. pneumoniae and K. pneumoniae. The inhibition. The zoneinhibition and inhibition zone and percentageinhibition percentage against S. aureus againstand S. aureusK. pneumoniae and K. pneumoniaewere shown were in Table shown2. Clearly,in Table the 2. bacteriaClearly, passingthe bacteria throughout passing the throughout fabric samples the fabric reveals samples that the reveals control that sample the doescontrol not sample have any does antibacterial not have any properties. antibacter Byial contrast, properties. after By treatment contrast, with after PHMB, treatment the spandexwith PHMB, fabric the shows spandex strong fabric antibacterial shows strong behaviour, antibacterial particularly behaviour, for particularly the gram-positive for the S.gram-positive aureus with theS. aureus inhibition withzone the inhibition of 2.40 mm, zone which of 2.40 is farmm, greater which than is far that greater for the than gram- that negativefor the gram-negativeK. pneumoniae .K. The pneumoniae reason for. The this reason could befor due this to could the fact be due that toS. aureusthe factis that more S. vulnerableaureus is more to the vulnerable antibacterial to the agent antibacterial PHMB than agentK. pneumoniaePHMB than. TheK. pneumoniae quantitative. The analysis quan- furthertitative showedanalysis that further the spandexshowed that fabric the after spandex PHMB fabric treatment after PHMB has 100% treatment inhibitory has action 100% againstinhibitory both actionS. aureus againstand bothK. pneumoniaeS. aureus and. The K. pneumoniae mechanism. The of actionmechanism could of be action explained could bybe theexplained fact that by PHMBthe fact molecules that PHMB can molecu disruptles thecan microbialdisrupt the membrane microbial andmembrane selectively and condensesselectively thecondenses chromosomes, the chromosomes, causing microbe causing death microbe [14]. death [14].

Polymers 13 Polymers 20212021,, 13,, 2122 2122 5 5of of 7 7

FigureFigure 3. 3. ImagesImages of of the the qualitative qualitative analysisanalysis forfor antibacterialantibacterial activitiesactivities of of PHMB-coated PHMB-coated fabric fabric samples sam- plesagainst againstS. aureus S. aureus(SA )(SA and) andK. pneumoniae K. pneumoniae(KP). (KP).

Table 2. Inhibition zone and inhibition percentage of PHMB-treated spandex fabrics against S. Table 2. Inhibition zone and inhibition percentage of PHMB-treated spandex fabrics against S. aureus aureus (SA) and K. pneumoniae (KP). (SA) and K. pneumoniae (KP). Inhibition Zone/mm Inhibition/% Sample Inhibition Zone/mm Inhibition/% Sample SA KP SA KP Control SA0 KP0 SAN/A KPN/A PHMB-treatedControl spandex fabric 0 2.40 0 1.15 N/A 100 N/A 100 PHMB-treated spandex fabric 2.40 1.15 100 100 3.4. Hand Feel Analysis 3.4. HandThe PHMB Feel Analysis coating may affect the hand feel properties of spandex fabric. Hence, the hand Thefeel PHMBof PHMB coating treated may spandex affect was the handevaluated feel propertiesand shown of in spandex Table 3. fabric. Clearly, Hence, after coatingthe hand with feel PHMB, of PHMB both treated resilience spandex and softness was evaluated of spandex and fabric shown have in Tablea negligible3. Clearly, de- crease,after coating whereas with there PHMB, is a slight both resilience increase in and the softness smoothness. of spandex These fabric results have show a negligible that the PHMBdecrease, coating whereas slightly there affects is a slight the hand increase feel in properties the smoothness. of spandex. These However, results show the wrinkle that the recoveryPHMB coating saw a slightlysignificant affects increase the hand from feel 65.2% properties to 73.16% of spandex. in comparison However, to the wrinklecontrol sample.recovery This saw suggests a significant that th increasee PHMB from coating 65.2% enhances to 73.16% the wrinkle in comparison recovery to of the spandex. control sample. This suggests that the PHMB coating enhances the wrinkle recovery of spandex. Table 3. Hand feel properties of PHMB-coated spandex fabric.

Table 3. HandSample feel properties of PHMB-coatedResilience spandexSoftness fabric. Smoothness Wrinkle Recovery/% Control 41.85 88.58 54.44 65.2 Wrinkle PHMB-treatedSample spandex fabric Resilience 39.69 88.37 Softness 55.56 Smoothness 73.16 Recovery/%

4. ConclusionsControl 41.85 88.58 54.44 65.2 PHMB-treated spandex fabric 39.69 88.37 55.56 73.16 The antiviral activity of the PHMB-treated spandex fabric was investigated in the present study against Feline coronavirus. BPB testing shows that PHMB was successfully 4. Conclusions coated on the surface of fabric. The antiviral analysis shows that the PHMB-treated span- dex fabricThe antiviralkilled 99% activity of the ofcoronavirus the PHMB-treated within 2 h spandex contact, fabricwhich wassuggests investigated that the inspan- the dexpresent fabric study treated against with FelinePHMB coronavirus. could be used BPB for testing developing shows antiviral that PHMB clothing was (e.g., successfully gloves coated on the surface of fabric. The antiviral analysis shows that the PHMB-treated spandex in Figure 4) against coronaviruses for containing the transmission of COVID-19 from high- fabric killed 99% of the coronavirus within 2 h contact, which suggests that the spandex risk surfaces. Moreover, both qualitative and quantitative antibacterial analyses demon- fabric treated with PHMB could be used for developing antiviral clothing (e.g., gloves in strated that the spandex fabric has excellent antibacterial activity after treatment with Figure4) against coronaviruses for containing the transmission of COVID-19 from high-risk PHBM, particularly for the gram-positive S. aureus. Hand feel analysis showed that PHMB surfaces. Moreover, both qualitative and quantitative antibacterial analyses demonstrated coating does not visibly affect the hand feel properties such as resilience, softness, and that the spandex fabric has excellent antibacterial activity after treatment with PHBM, smoothness, but can obviously improve the wrinkle recovery of Spandex fabric. particularly for the gram-positive S. aureus. Hand feel analysis showed that PHMB coating

Polymers 2021, 13, 2122 6 of 7 Polymers 2021, 13, 2122 2 of 7

breathabilitydoes not visibly and affect hygroscopicity. the hand feel These properties proble suchms can as resilience,be addressed softness, by blending and smoothness, cotton or otherbut can breathable obviously materials improve with the wrinklespandex recovery [8]. of Spandex fabric.

Figure 4.TextileSpandex-based fibers play antiviral a significant gloves on role various in the daily transmission life scenarios. of infectious diseases because of the vulnerability to microbial attack. The outbreak of COVID-19 around the world has goneAuthor on Contributions: for one and aConceptualization, half years and has C.-W.K. already and resulted C.-H.W.; methodology,in huge losses W.-Y.W. [9]. It and has S.-L.Y.; been reportedinvestigation, that W.-Y.W.COVID-19 and could S.-L.Y.; survive resources, for C.-W.K.48 h on andcloth C.-H.W.; [10], which data makes curation, it indispensable W.-Y.W. and S.- toL.Y.; develop writing—original antiviral fabrics draft preparation, with potential W.-Y.W.; application writing—review in protective and editing, clothing. C.-W.K., In S.-L.Y. order and to achieveC.-H.W.; antiviral visualization, activity, W.-Y.W. a wide and variety S.-L.Y.; of supervision, chemicals C.-W.K.;have been project applied administration, to textile products C.-W.K.; funding acquisition, C.-W.K. All authors have read and agreed to the published version of the such as triclosan via finishing technology [11]. Apart from the broad-spectrum bacteri- manuscript. cidal properties, one of the major problems for these treated antiviral fabrics is the dura- bilityFunding: againstThis wear research and was household funded by washing. the Hong Kong Polytechnic University, grant number ZVQJ and ZVNM.Poly(hexamethylene biguanide) hydrochloride (PHMB) is a well-known commercial bactericideInstitutional that Review has Boardbeen widel Statement:y usedNot in applicable.a variety of areas such as the food industry and recreational water because of its low toxicity and broad-spectrum bactericidal properties Informed Consent Statement: Not applicable. [12,13]. PHMB is composed of repeating biguanidine units spaced by hydrophobic hexa- methylenData Availability hydrocarbon Statement: chainsThe (Figure data presented 1). The antibacterial in this study aremechanism available of on PHMB request is from highly the dependentcorresponding on author. the cationic biguanide moieties that can interact with the negatively chargedConflicts phosphate of Interest: Thehead authors groups declare of bacterial no conflict cell of membrane interest. and finally cause cell death [14,15]. In the textile industry, PHMB is generally used through the processes of padding, References spraying, conventional exhaust method or pad–dry–cure [16]. PHMB shows strong affin- 1. Singha, K. Analysis of Spandex/Cottonity to cellulosic Elastomeric fibers due Properties: to electrostatic Spinning andinteraction Applications. and Int.hydrogen J. Compos. bonding Mater. 2012 and, 2the, 11–16. ad- [CrossRef] sorption follows typical Langmuir isotherms at lower concentrations [13]. Therefore, the 2. Tezel, S.; Kavu¸sturan,Y. Experimentalfabrics treated Investigation with PHMB of Effectsdisplay of excellent Spandex durability Brand and against Tightness household Factor on laundering Dimensional [17]. and Physical Properties of Cotton/SpandexMoreover, SinglePHMB has Fabrics.modest Text.virucidal Res. J. 2008activity, 78, 966–976.against [non-envelopedCrossRef] viruses such as 3. Islam, S.; Alam, S.M.; Akter,HIV-1 S. The [18]. consequences The mechanism of temperature of action on the of shrinkagePHMB-bas propertiesed biocides of cotton is to spandexinteract wovenwith the fabric. viralJ. Text. Polym. 2019, 7, 2–7. capsid and to lead to virus death [19]. Hence, the present study aims to develop an anti- 4. Li, Q.; Ni, L.; Wang, J.; Quan, H.; Zhou, Y. Establishing an ultrasound-assisted activated peroxide system for efficient and sustainable scouring-bleachingviral of fabric cotton/spandex against COVID-19 fabric. Ultrason. with Sonochem.potential 2020application, 68, 105220. for [protectiveCrossRef][ PubMedclothing] by using 5. Akter, N. analysisPHMB. of spandex incorporated single jersey fabrics for sportswear. Indian J. Sci. Technol. 2020, 13, 1998–2009. [CrossRef] 6. Gohain, J.; Raichurkar, P. Study effect of different parameters in heat setting of spandex fabric and other quality. J. Text. Excell. 2011, 3, 41–49. 7. Schollenberger, C.S.; Stewart, F.D. Thermoplastic Polyurethane Hydrolysis Stability. J. Elastoplast. 1971, 3, 28–56. [CrossRef] 8. Gokarneshan, N.; Thangamani, K. An investigation into the properties of cotton/spandex and polyester/spandex knitted fab-rics. J. Text. Inst. 2010, 101, 182–186. [CrossRef] 9. Team, I.C.F. Modeling COVID-19Figure scenarios 1. Chemical for thestructure United of States. PHMB.Nat. Med. 2021, 27, 94–105. 10. Chin, A.W.H.; Chu, J.T.S.; Perera, M.R.A.; Hui, K.P.Y.; Yen, H.L.; Chan, M.C.W.; Peiris, M.; Poon, L.L.M. Stability of SARS-CoV-2 in different environmental conditions.2. MaterialsLancet and2020 Methods, 1, e145. 11. Iyigundogdu, Z.U.; Demir, O.; Asutay, A.B.; Sahin, F. Developing Novel Antimicrobial and Antiviral Textile Products. Appl. Spandex-knitted fabric (cotton 92%/spandex 8%) with weight 180 g/cm2 was used in Biochem. Biotechnol. 2017, 181, 1155–1166. [CrossRef][PubMed] this study. Poly(hexamethylene biguanide) hydrochloride (PHMB) as a 20% w/v aqueous

Polymers 2021, 13, 2122 7 of 7

12. De Paula, G.F.; Netto, G.I.; Mattoso, L.H.C. Physical and Chemical Characterization of Poly(hexamethylene biguanide) Hy- drochloride. Polymers 2011, 3, 928–941. [CrossRef] 13. Blackburn, R.S.; Harvey, A.; Kettle, L.L.; Payne, J.D.; Russell, S.J. Sorption of Poly(hexamethylenebiguanide) on Cellulose: Mechanism of Binding and Molecular Recognition. Langmuir 2006, 22, 5636–5644. [CrossRef][PubMed] 14. Chindera, K.; Mahato, M.; Sharma, A.K.; Horsley, H.; Kloc-Muniak, K.; Kamaruzzaman, N.F.; Kumar, S.; McFarlane, A.; Stach, J.; Bentin, T.; et al. The antimicrobial polymer PHMB enters cells and selectively condenses bac-terial chromosomes. Sci. . 2016, 6, 23121. [CrossRef][PubMed] 15. Kaehn, K. Polihexanide: A Safe and Highly Effective Biocide. Ski. Pharmacol. Physiol. 2010, 23, 7–16. [CrossRef][PubMed] 16. Wang, W.-Y.; Kan, C.-W. An eco-friendly method: Bromophenol blue (BPB) applied for dyeing cotton fabrics coated with cationic finishing agents. Cellulose 2020, 27, 9045–9059. [CrossRef] 17. Lau, J.Y.N.; Chan, D.S.B.; Chiou, J.; Kan, C.W.; Lam, K.H.; Lam, W.H.; Yung, K.F. Durable Antimicrobial Treatment of Textile for Use in Healthcare Environment. U.S. Patent Application No. 17/045,659, 4 April 2019. 18. Pinto, F.; Maillard, J.-Y.; Denyer, S.; McGeechan, P. Polyhexamethylene biguanide exposure leads to viral aggregation. J. Appl. Microbiol. 2009, 108, 1880–1888. [CrossRef][PubMed] 19. Pinto, F. Mechanisms of Action of Polyhexamethylene Biguanide-Based Biocides Against Non-Enveloped Virus. Ph.D. Thesis, Cardiff University, Cardiff, UK, 2010.