scholarly journals Water Vapor Permeability of Poly(vinyl alcohol) Films Modified by Graft Polymerizing Styrene by Means of Irradiation

1973 ◽  
pp. 1244-1246
Author(s):  
Toshihiko Yoshitake
Keyword(s):  
Water Vapor ◽  
Vinyl Alcohol ◽  
Water Vapor Permeability ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability

Environmental-Friendly Soy Protein Isolate/Poly (Vinyl Alcohol) Blend Packaging Films: Water Vapor Permeability

2010 ◽  
Vol 96 ◽  
pp. 75-79 ◽  
Author(s):  
Jun Feng Su ◽  
Wen Long Xia ◽  
Wen Li ◽  
Ke Man Jin
Keyword(s):  
Water Vapor ◽  
Soy Protein ◽  
Vinyl Alcohol ◽  
Soy Protein Isolate ◽  
Water Vapor Permeability ◽  
Protein Isolate ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability ◽  
Glycerol Water ◽  
Moisture Sensitivity

The aim of the present work was to investigate the moisture sensitivity of soy protein isolate (SPI) films blending with poly (vinyl alcohol) (PVA) plasticized by glycerol. Water vapor permeability (WVP) was measured based on the contents of PVA and glycerol in films. WVP values of various SPI/PVA films with/without glycerol were in the range of 8.25 and 10.9 g mm/m2 h kPa. The results showed that WVP values decreased with the increasing content of PVA. Moreover, XRD tests confirmed that the glycerol would insert into the macromolecular blending structure and destroy the crystalline of blends, and the crosslinkage between glycerol molecules and SPI reduced the interstitial spaces in protein matrix, thus allowing for decreasing diffusion rate of water molecules through the films.

Effects of low poly(vinyl alcohol) content on properties of biodegradable blowing films based on two modified starches

2015 ◽  
Vol 30 (7) ◽  
pp. 1017-1030 ◽  
Author(s):  
Wentao Wang ◽  
Hui Zhang ◽  
Yangyong Dai ◽  
Hanxue Hou ◽  
Haizhou Dong
Keyword(s):  
Water Vapor ◽  
Vinyl Alcohol ◽  
Composite Films ◽  
Water Vapor Permeability ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability ◽  
Electron Microscopic ◽  
X Ray ◽  
Modified Starches ◽  
Ray Patterns

Biodegradable films from hydroxypropyl distarch phosphate (HPDSP)/poly(vinyl alcohol) (PVA) and cationic starch/PVA blends were obtained by extrusion blowing at ratios of 100:0, 95:5, 90:10, 85:15, and 80:20. The morphology, X-ray patterns, transparency, mechanical properties, thermal properties, and water vapor permeability (WVP) of the films were measured and compared. Scanning electron microscopic micrographs of the films showed continuous matrix texture as well as better compatibility between modified starches and PVA. X-Ray diffraction indicated the formation of ordered crystalline structures in the films during extrusion blowing. The addition of PVA to modified starches significantly increased their tensile strength (TS, 3.92 MPa) while decreasing their water vapor permeability (WVP, 3.23 × 10−10 g m−1 s−1 Pa−1). The starch/PVA composite films did not show phase separation.

scholarly journals Mussel-Inspired Approach to Constructing Dual Network Coated Layered Clay for Enhanced Barrier and Antibacterial Properties of Poly(vinyl alcohol) Nanocomposites

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2093
Author(s):  
Long Mao ◽  
Jianda Xie ◽  
Huiqing Wu ◽  
Yuejun Liu
Keyword(s):  
Vinyl Alcohol ◽  
Antibacterial Properties ◽  
Water Vapor Permeability ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability ◽  
One Pot ◽  
Solution Casting Method ◽  
Uv Transmittance ◽  
Layered Clay ◽  
Double Hydroxides

Inspired by complexation and mussel adhesion of catechol groups in tannic acid (TA), organophilic layered double hydroxides (LDHs@TA-Ti) were synthesized by forming a one-pot assembled TA-titanium (Ti) dual network coating on the surface of layered clay for the first time. LDHs@TA-Ti/poly(vinyl alcohol) (PVA) nanocomposites were prepared by the solution casting method. The results show that TA-Ti(IV) and TiO2 coordination compounds are simultaneously formed due to hydrolysis of titanium tetrachloride and complexation of TA in aqueous solution. Upon TA-Ti coatings onto the surface of LDHs, the antibacterial rate of LDHs@TA-Ti is up to 99.98%. Corresponding LDHs@TA-Ti/PVA nanocomposites also show outstanding antibacterial properties. Compared with pure PVA, LDHs@TA-Ti/PVA nanocomposites show a 40.9% increase in tensile strength, a 17.5% increase in elongation at break, a 35.9% decrease in oxygen permeability and a 26.0% decrease in water vapor permeability when adding 1 wt % LDHs@TA-Ti. UV transmittance (at 300 nm) of LDHs@TA-Ti/PVA nanocomposites decrease by 99.4% when the content of LDHs@TA-Ti reaches 3 wt %. These results indicate that PVA matrix incorporated with LDHs@TA-Ti could be used as a potential active packaging material to extend the shelf life of food products.

scholarly journals Active Biodegradable Polyvinyl Alcohol–Hemicellulose/Tea Polyphenol Films with Excellent Moisture Resistance Prepared via Ultrasound Assistance for Food Packaging

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 219
Author(s):  
Yining Wang ◽  
Jinhui Li ◽  
Xin Guo ◽  
Haisong Wang ◽  
Fang Qian ◽  
...  
Keyword(s):  
Water Vapor ◽  
High Performance ◽  
Food Packaging ◽  
Composite Films ◽  
Water Vapor Permeability ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability ◽  
Moisture Resistance ◽  
Film Material ◽  
Strength Performance

Poor water-vapor barriers and mechanical properties are common problems of biobased films. To maintain food quality, the barrier and its strength performance need to be improved. Tea polyphenols (TP) are a natural active substance, and their benzene ring structure provides a barrier for them as a film material. Films that incorporate TP also have enriched functionalities, e.g., as antioxidants. Here, active poly (vinyl alcohol) (PVA)-hemicellulose (HC)/TP films with good moisture resistance and antioxidant capacity were prepared via ultrasound assistance. The effects of TP incorporation and ultrasonication on the physical, antioxidant, and micromorphological properties of the films were investigated. Results showed that the addition of TP improved the thermal stability and water-vapor permeability (WVP) of the composite films. When a PVA-HC/TP composite film with a PVA-HC to TP mass ratio of 100:10 was treated with ultrasonication for 45 min, tensile strength was 25.61 Mpa, which was increased by 54% from the film without any treatment, and water-vapor permeability (WVP) value declined from 49% to 4.29 × 10−12 g·cm/cm2·s·Pa. More importantly, the films’ DPPH scavenging activity increased to the maximal levels of 85.45%. In short, these observations create a feasible strategy for preparing high-performance biodegradable active-packaging films.

Morphology and Properties of Blends of Poly(3-hydroxybutyrate) with Poly(vinyl alcohol)

2016 ◽  
Vol 10 (3) ◽  
pp. 311-316
Author(s):  
Anatoly Olkhov ◽  
◽  
Alexey Iordanskii ◽  
Keyword(s):  
Water Vapor ◽  
Relative Elongation ◽  
Composite Films ◽  
Tensile Modulus ◽  
Water Vapor Permeability ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability ◽  
X Ray ◽  
Extruded Films ◽  
Sensitive Characteristics

The structure of extruded films based on blends of polyvinyl alcohol and poly(3-hydroxybutyrate) (PHB) was studied for various compositions. The methods of DSC and X-ray analysis were used. As the phase-sensitive characteristics of the composite films, diffusion and water vapor permeability were also investigated. In addition, the tensile modulus and relative elongation-at-break were measured. Changes in the glass transition temperature of the blends and constant melting points of the components show their partial compatibility in intercrystallite regions. At the content of PHB in the composite films equal to 20–30 wt % their mechanical characteristics and water diffusion coefficients are dramatically changed. This fact, along with the analysis of the X-ray diffractograms, indicates a phase inversion in the above narrow concentration interval. The complex pattern of the kinetic curves of water vapor permeability is likely to be related to additional crystallization, which is induced in the composite films in the presence of water

scholarly journals Influence of Ammonium Zirconium Carbonate on Properties of Poly(vinyl alcohol)/Xylan Composite Films

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xiao-feng Chen ◽  
Jun-li Ren ◽  
Ling Meng
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Vinyl Alcohol ◽  
Positive Impact ◽  
Raw Materials ◽  
Composite Films ◽  
Water Vapor Permeability ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability ◽  
Ammonium Zirconium Carbonate

A series of composite films were prepared using poly(vinyl alcohol) (PVA) and xylan as degradable raw materials under the addition of glycerol and ammonium zirconium carbonate (AZC). The influences of AZC on the mechanical properties, water-resisting properties, thermal stability, solubility (S), and water vapor permeability of PVA/xylan composite films were comparatively discussed. The results showed that AZC had a positive impact on improving the water resistance and mechanical properties of composite films especially for elongation at break (EAB). With increasing the AZC amounts from 0% to 15%, EAB increased rapidly from 18.5% to 218.0%, and theSvalues decrease from 11.64% to 8.64%. When the AZC amount reached 15%, the tensile strength still performed well (22.10 MPa). The great compatibility of components in composite films was also observed. Moreover, the addition of AZC had great influences on the thermal stability of composite films and the degradation in soil.

scholarly journals Preparation and Characterization of a Bioartificial Polymeric Material: Bilayer of Cellulose Acetate-PVA

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Andrés Bernal-Ballén ◽  
Ivo Kuritka ◽  
Petr Saha
Keyword(s):  
Mechanical Properties ◽  
Water Vapor ◽  
Cellulose Acetate ◽  
Polymeric Material ◽  
Gas Permeability ◽  
Water Vapor Permeability ◽  
Poly Vinyl Alcohol ◽  
Vapor Permeability ◽  
Scanning Calorimetry ◽  
Well Differentiated

A new bioartificial polymeric material consisting of a bilayer of cellulose acetate and poly(vinyl alcohol) was successfully obtained by casting method. The material was characterized by Fourier transform infrared spectroscopy, contact angle, scanning electron microscopy, differential scanning calorimetry, gas permeability, water vapor permeability, and mechanical properties. The characterization indicates that two distinct and well-differentiated surfaces were achieved without detriment to the bulk properties. The interaction between natural and synthetic polymers indeed enhanced the gas permeability as well as the water vapor permeability in comparison to the original components, although mechanical properties were not substantially boosted by the combination of both. Moreover, beyond the interface, there were no detected interactions between the polymers as can be evidenced by the presence of a uniqueTgin the bilayer. The amalgamation of the relatively good mechanical properties with the two differentiated surfaces and the improvement of the permeability properties could indicate the potential of the material for being used in medicine.

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