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. 2021 Dec 18;13(24):4447.
doi: 10.3390/polym13244447.

Sandwich-Structured, Hydrophobic, Nanocellulose-Reinforced Polyvinyl Alcohol as an Alternative Straw Material

Chun-Tu Chou  1 , Shih-Chen Shi  1 , Chih-Kuang Chen  2
Affiliations

Sandwich-Structured, Hydrophobic, Nanocellulose-Reinforced Polyvinyl Alcohol as an Alternative Straw Material

Chun-Tu Chou et al. Polymers (Basel). .

Abstract

An environmentally friendly, hydrophobic polyvinyl alcohol (PVA) film was developed as an alternative to commercial straws for mitigating the issue of plastic waste. Nontoxic and biodegradable cellulose nanocrystals (CNCs) and nanofibers (CNFs) were used to prepare PVA nanocomposite films by blade coating and solution casting. Double-sided solution casting of polyethylene-glycol-poly(lactic acid) (PEG-PLA) + neat PLA hydrophobic films was performed, which was followed by heat treatment at different temperatures and durations to hydrophobize the PVA composite films. The hydrophobic characteristics of the prepared composite films and a commercial straw were compared. The PVA nanocomposite films exhibited enhanced water vapor barrier and thermal properties owing to the hydrogen bonds and van der Waals forces between the substrate and the fillers. In the sandwich-structured PVA-based hydrophobic composite films, the crystallinity of PLA was increased by adjusting the temperature and duration of heat treatment, which significantly improved their contact angle and water vapor barrier. Finally, the initial contact angle and contact duration (at the contact angle of 20°) increased by 35% and 40%, respectively, which was a significant increase in the service life of the biodegradable material-based straw.

Keywords: cellulose; hydrophobic; polyvinyl alcohol; sandwich structure; straw.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Preparation of PVA + CNC/CNF nanocomposite films.
Figure 2
Figure 2
Preparation of hydrophobic materials and sandwich-structured PVA-based hydrophobic composite films.
Figure 3
Figure 3
ASTM E96/E96M-16 upright cup and the wet cup method.
Figure 4
Figure 4
XRD patterns of the PVA + CNC/CNF nanocomposite films. The AA–KK notations are described henceforth. AA: Neat PVA, BB: PVA + 0.5 wt% CNCs, CC: PVA + 1.0 wt% CNCs, DD: PVA + 1.5 wt% CNCs, EE: PVA + 2.0 wt% CNCs, FF: PVA + 2.5 wt% CNCs, GG: PVA + 3.0 wt% CNCs, HH: Neat CNCs, II: PVA + 0.5 wt% CNFs, JJ: PVA + 1.0 wt% CNFs, and KK: Neat CNFs.
Figure 5
Figure 5
Grain sizes of the PVA + CNC/CNF nanocomposite films.
Figure 6
Figure 6
Contact angles of the PVA + CNC/CNF nanocomposite films.
Figure 7
Figure 7
Water vapor permeabilities of the PVA + CNC/CNF nanocomposite films.
Figure 8
Figure 8
(a) Tg and (b) Xc values of the PVA + CNC/CNF nanocomposite films.
Figure 9
Figure 9
(a) TGA and (b) DTG profiles of the PVA + CNC/CNF nanocomposite films.
Figure 10
Figure 10
DSC analysis of the (a) untreated and (b) heat-treated hydrophobic materials.
Figure 11
Figure 11
(a) TGA and (b) DTG profiles of the hydrophobic materials.
Figure 12
Figure 12
XRD patterns of untreated and heat-treated (a) PEG–PLA(70) and PEG–PLA(70) + neat PLA, and (b) PEG–PLA(140) and PEG–PLA(140) + neat PLA specimens. The temperatures, durations, and notations corresponding to this heat treatment are listed in Table 2.
Figure 13
Figure 13
Contact angle analyses of untreated and heat-treated (a) PEG–PLA(70)_90 °C, (b) PEG–PLA(70) + neat PLA_90 °C, (c) PEG–PLA(70) + neat PLA_125 °C, (d) PEG–PLA(140)_100 °C, (e) PEG–PLA(140) + neat PLA_100 °C, and (f) PEG–PLA(140) + neat PLA_125 °C samples. The durations and notations corresponding to this heat treatment are shown in Table 2.
Figure 14
Figure 14
Water vapor permeabilities of the sandwich-structured PVA-based (a) PEG–PLA(70) and PEG–PLA(70) + neat PLA, and (b) PEG–PLA(140) and PEG–PLA(140) + neat PLA hydrophobic composite films. The temperatures, durations, and notations corresponding to this heat treatment are listed in Table 2.
Figure 15
Figure 15
XPS profile of the sandwich-structured PVA-based hydrophobic composite film.
Figure 16
Figure 16
Contact angles of the sandwich-structured PVA-based hydrophobic composite film and commercially available PP.
Figure 17
Figure 17
Water uptake behavior of the sandwich-structured PVA-based hydrophobic composite film and a commercial PP specimen.
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References

    1. Plastic Pollution. [(accessed on 10 November 2021)]. Available online: https://ourworldindata.org/plastic-pollution.
    1. Camacho W., Karlsson S. NIR, DSC, and FTIR as quantitative methods for compositional analysis of blends of polymers obtained from recycled mixed plastic waste. Polym. Eng. Sci. 2001;41:1626–1635. doi: 10.1002/pen.10860. - DOI
    1. Majewsky M., Bitter H., Eiche E., Horn H. Determination of microplastic polyethylene (PE) and polypropylene (PP) in environmental samples using thermal analysis (TGA-DSC) Sci. Total Environ. 2016;568:507–511. doi: 10.1016/j.scitotenv.2016.06.017. - DOI - PubMed
    1. Gall S.C., Thompson R.C. The impact of debris on marine life. Mar. Pollut. Bull. 2015;92:170–179. doi: 10.1016/j.marpolbul.2014.12.041. - DOI - PubMed
    1. Eriksen M., Lebreton L.C., Carson H.S., Thiel M., Moore C.J., Borerro J.C., Galgani F., Ryan P.G., Reisser J. Plastic pollution in the world’s oceans: More than 5 trillion plastic pieces weighing over 250,000 tons afloat at sea. PLoS ONE. 2014;9:e111913. doi: 10.1371/journal.pone.0111913. - DOI - PMC - PubMed

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