Effect of trifluoroacetic acid on the properties of polyvinyl alcohol and polyvinyl alcohol–cellulose composites

Guzmán-Puyol, Susana; Ceseracciu, Luca; Heredia‐Guerrero, José A.; Anyfantis, George C.; Cingolani, R.; Athanassiou, Athanassia

doi:10.1016/j.cej.2015.04.092

Cited by 91 publications

(41 citation statements)

References 53 publications

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“…As shown in Fig. 1c, the infrared spectrum displays typical PVA absorption bands such as -OH stretching at 3276 cm −1 , asymmetric and symmetric -CH2 stretching at 2939 and 2908 cm −1 , respectively, -OH deformation vibration at 1672 and 1564 cm −1 , -CH2 bending at 1416 cm −1 and C-O stretching at 1099 cm −1 [32]. For the TiO2 modified with TFA, 1470 and 1639 cm −1 were the symmetric and asymmetric stretching of a carbonyl group, respectively.…”

Section: Resultsmentioning

confidence: 99%

Multicycle photocatalytic reduction of Cr(VI) over transparent PVA/TiO2 nanocomposite films under visible light

et al. 2017

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Photocatalytic reduction of hexavalent chromium in wastewater has been widely investigated as an attractive treatment method. In this work, we reported an efficient method for photocatalytic reduction of Cr(VI) over transparent polyvinyl alcohol/titanium dioxide (PVA/TiO2) nanocomposite films under sunlight irradiation. The transparent PVA/TiO2 nanocomposite films were prepared by a simple hydrothermal method combined with a solution casting process. The results revealed that the anatase TiO2 nanoparticles with size less than 10 nm were in-situ generated in PVA matrix, which endowed the films with high transparency. Photocatalytic reduction of Cr(VI) over PVA/TiO2 nanocomposite films exhibited superior visible light photocatalytic activity. Mechanism investigation demonstrated that the PVA acted not only as a transparent support for TiO2 nanoparticles, but also as holes scavengers simultaneously to improve the separation of photogenerated holes and electrons. Meanwhile, the transparent PVA/TiO2 nanocomposite films displayed remarkable stability and excellent recyclability during multicycle Cr(VI) photoreduction. Furthermore, the PVA/TiO2 nanocomposite films showed selective adsorption ability for Cr(III), and thus totally removal of Cr(VI) was achieved after photoreduction process.

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Section: Resultsmentioning

confidence: 99%

Multicycle photocatalytic reduction of Cr(VI) over transparent PVA/TiO2 nanocomposite films under visible light

et al. 2017

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“…The peak at 1650 cm −1 is associated to OH deformation vibrations. The absorption peaks at 1420 and 1090 cm −1 are attributed to the CH 2 bending and CO stretching of PVA groups, respectively . The peaks at 1330 and 850 cm −1 are also attributed to PVA, namely, to the CH 2 bending vibrations.…”

Section: Resultsmentioning

confidence: 96%

“…It refers to the initial volatilization of moisture, and possible remaining residues of solvent (DMF), from the specimens due to evaporation or dehydration of hydrated cations . Because the first degradation event for PVA reaches temperatures above 100 °C, it is possible that remaining molecules of DMF to act as plasticizers, as consequence of the initial degradation of the sections of polymer chains that interacted with the solvent via hydrogen bonding and, as such, being more difficult to eliminate . Usually, PVA is characterized by only two degradation steps.…”

Section: Resultsmentioning

confidence: 99%

Antimicrobial action and clotting time of thin, hydrated poly(vinyl alcohol)/cellulose acetate films functionalized with LL37 for prospective wound‐healing applications

Felgueiras

Teixeira

Tavares

et al. 2019

J of Applied Polymer Sci

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Poly(vinyl alcohol)/cellulose acetate (PVA/CA) films were prepared via a new method that combines principles from solvent casting and phase inversion. To guarantee some degree of flexibility, films were produced with a higher percentage of PVA compared to CA, from 90/10 to 50/50. The antimicrobial peptide (AMP) LL37 was then anchored using dopamine as a binding agent. Films were characterized in terms of functional groups, thermal stability, tensile strength, porosity, swelling, and degradation (stability in physiological media at different pHs). The antimicrobial performance of LL37 surface-modified films was tested against Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli in dynamic environment and in the presence and absence of an albumin interface. LL37 treated films demonstrated great antibacterial efficacy against the three kinds of bacteria, ≈75% inhibition for S. aureus, ≈85% for S. epidermidis, and ≈60% for E. coli, regardless of PVA/CA ratio. Presence of albumin reduced bacteria inhibition in all tested groups, most likely due to the binding of the protein molecules to the antimicrobial agents, reducing the free fraction available for bacterial killing. Films treated with LL37 accelerated clotting time (≈10 min) above vancomycin and bare surfaces, demonstrating great capacity to activate the intrinsic coagulation cascade.

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“…In many industrial processes such as food packaging, polymeric materials are required to have good thermal stability to endure high heat and humidity retort treatment (Guzman‐Puyol et al, ). TGA curves were shown in Figure a to reveal thermal degradation process of PVA films incorporated with different concentration GTE.…”

Section: Resultsmentioning

confidence: 99%

“…In many industrial processes such as food packaging, polymeric materials are required to have good thermal stability to endure high heat and humidity retort treatment (Guzman-Puyol et al, 2015). TGA curves were shown in Figure 3a 2008; L opez de Dicastillo et al, 2013;Nie et al, 2015;Sun et al, 2014).…”

Section: Thermogravimetric Analysis (Tga)mentioning

confidence: 99%

Development of moisture-absorbing and antioxidant active packaging film based on poly(vinyl alcohol) incorporated with green tea extract and its effect on the quality of dried eel

Chen

Xie

Yang

et al. 2017

J Food Process Preserv

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Active packaging film with functions of moisture-absorbing and antioxidant activity was developed based on poly(vinyl alcohol) (PVA) incorporated with green tea extract (GTE). The effects of GTE concentrations of 0, 0.5, 1, 1.5, and 2% on the physical, structural, and antioxidant properties of PVA films were investigated. The PVA film containing 2% GTE had lower moisture absorbing efficiency relatively and better antioxidant activity through DPPH radical-scavenging ability experiment. A packaging system of GTE-incorporated PVA films was applied to package dried eel and quality of dried eel was evaluated during storage. The result showed that dried eel packed with GTE-incorporated PVA films showed lower weight change, peroxide value and TBARS value during storage than that packed without PVA films or with PVA films but no GTE. The PVA film containing 2% GTE showed the best quality protective effectiveness to prevent the dried eel from absorbing moisture and oxidizing of lipid. Practical applicationsPoly(vinyl alcohol) (PVA) is a synthetic polymer that is widely used in packaging applications because of its excellent film forming, biodegradability, good mechanical, and gas barrier properties.The present study evidenced that the PVA films incorporated with GTE showed good quality protective effectiveness to prevent the dried eel packed with these films from absorbing moisture and oxidizing of lipid. This active packaging film could be used as inner layer or intermediate layer in the composite packaging film system to improve the storage quality of moisture-sensitive and high-fat food. Based on this concept, the moisture-absorbing agents and antioxidant can be incorporated into the packaging structures to develop an active multifunctional food packaging material potentially to remove or reduce moisture inside the food packaging system instead of desiccants and preservative added in the food.

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Effect of trifluoroacetic acid on the properties of polyvinyl alcohol and polyvinyl alcohol–cellulose composites

Cited by 91 publications

References 53 publications

Multicycle photocatalytic reduction of Cr(VI) over transparent PVA/TiO2 nanocomposite films under visible light

Multicycle photocatalytic reduction of Cr(VI) over transparent PVA/TiO2 nanocomposite films under visible light

Antimicrobial action and clotting time of thin, hydrated poly(vinyl alcohol)/cellulose acetate films functionalized with LL37 for prospective wound‐healing applications

Development of moisture-absorbing and antioxidant active packaging film based on poly(vinyl alcohol) incorporated with green tea extract and its effect on the quality of dried eel

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