Morphology of poly(3-hydroxybutyrate)–polyvinyl alcohol extrusion films

2015 ◽  
Vol 35 (8) ◽  
pp. 765-771 ◽  
Author(s):  
Anatoly A. Ol’khov ◽  
Alexey L. Iordanskii ◽  
Tamara P. Danko

Abstract The morphology of extruded films based on blends of polyvinyl alcohol (PVA) and poly(3-hydroxybutyrate) (PHB) was studied for various compositions. The methods of differential scanning calorimetry (DSC) and X-ray analysis were used. The phase-sensitive characteristics of the composite films, diffusion and water vapor permeability were also investigated. Processes of binding of water and swelling cause the first areas; processes of a relaxation and transition of structure of composites to an equilibrium condition, the second. In addition, the tensile modulus and relative elongation-at-break were measured. Changes in the glass transition temperature (Tg) of the blends and constant melting points of the components show their partial compatibility in intercrystalline regions. At a content of PHB in the composite films equal to 20–30% wt., the 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.

2016 ◽  
Vol 10 (3) ◽  
pp. 311-316
Author(s):  
Anatoly Olkhov ◽  
◽  
Alexey Iordanskii ◽  

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


2016 ◽  
Vol 36 (2) ◽  
pp. 181-188 ◽  
Author(s):  
Aleksandra Buzarovska ◽  
Gordana Bogoeva-Gaceva ◽  
Radek Fajgar

Abstract Poly(lactic acid) (PLA) based composite films with different content of talc (5–15 wt%) were prepared by the solvent casting method. The effect of talc on morphological, structural, thermal, barrier and mechanical properties of neat PLA was investigated. The PLA/talc composites revealed a polymorphic crystalline structure, as demonstrated by X-ray diffraction (XRD) study and differential scanning calorimetry (DSC) analysis. The PLA/talc composites also exhibited significantly improved barrier properties (up to 55% compared to neat PLA), as shown by water vapor permeability (WVP) tests. The puncture measurements showed improved mechanical properties at lower content of talc (up to 5 wt%), and increased brittleness of the PLA/talc composite films at higher talc concentrations.


2015 ◽  
Vol 30 (7) ◽  
pp. 1017-1030 ◽  
Author(s):  
Wentao Wang ◽  
Hui Zhang ◽  
Yangyong Dai ◽  
Hanxue Hou ◽  
Haizhou Dong

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.


Optimization of film formula-based kappa-carrageenan and polyvinyl alcohol (PVA) was studied using a two-level, two-factor Design Expert 11® by Response Surface Methodology (RSM) Central Composite Design (CCD). The aim of this study was to obtain the optimal concentration of kappa-carrageenan and polyvinyl alcohol in producing films. The influence composition ⱪ-carrageenan and polyvinyl alcohol was characterized. The results showed the effects of k-carrageenan and polyvinyl alcohol had a significant effect on the response thickness, tensile strength, burst strength, elongation, solubility, water vapor barrier, opacity, color, and moisture content. The optimized condition for production k-carrageenan and PVA was 1.21% carrageenan and 1.93% polyvinyl alcohol, which was giving film with thickness 0.044 mm, tensile strength 16.69 MPa, burst strength 167.86 kPa, elongation 81.79%, water solubility 65.04%, water vapor permeability 7.49 g/m s Pa x 10-11, opacity 2.31, ΔE 2.42, and moisture content 19.13%


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jinshu Liu ◽  
Xiaoyan Ma ◽  
Wenzhao Shi ◽  
Jianwei Xing ◽  
Chaoqun Ma ◽  
...  

Abstract Baicalin, an active flavonoid ingredient of Scutellaria baicalensis Georgi, was extracted by heat reflux extraction and showed the same significance UV absorption property with standard baicalin. Active films were prepared from polyvinyl alcohol (PVA) containing baicalin extract by casting method. The effect of baicalin extracts on the UV-blocking, optical, antioxidant property, water vapor permeability, swelling and mechanical properties of the films were studied. UV–vis transmittance spectra showed that PVA films incorporated with baicalin extract blocked ultraviolet light range from 280–400 nm even with low concentration of baicalin (0.5 wt%) and maintain the high transparency in visible spectrum. The outstanding UV-blocking properties of PVA films incorporated with baicalin extract were also confirmed by Rhodamine B degradation. Baicalin conferred antioxidant properties to PVA films as determined by DPPH radical scavenging activity. Due to the interaction between hydroxy groups of baicalin and PVA molecule, water vapor permeability, swelling and elongation at break of the films were decreased accompanied with the increasing in tensile strength and Young’s modulus. FTIR reveal that the interaction between PVA molecules was significant changed by the introduction of baicalin. These results suggest that PVA film incorporated with baicalin extract can be used for the development of functional protective film.


Author(s):  
Jie Liu ◽  
Yanchun Liu ◽  
Eleanor M. Brown ◽  
Zhengxin Ma ◽  
Cheng-Kung Liu

The leather industry generates considerable amounts of solid waste and raises many environmental concerns during its disposal. The presence of collagen in these wastes provides a potential protein source for the fabrication of bio-based value-added products. Herein, a novel composite film was fabricated by incorporating vegetable-tanned collagen fiber (VCF), a mechanically ground powder-like leather waste, into a chitosan matrix and crosslinked with genipin. The obtained composite film showed a compact structure and the hydrogen bonding interactions were confirmed by FTIR analysis, indicating a good compatibility between chitosan and VCF. The optical properties, water absorption capacity, thermal stability, water vapor permeability and mechanical properties of the composite films were characterized. The incorporation of VCF into chitosan led to significant decreases in opacity and solubility of the films. At the same time, the mechanical properties, water vapor permeability and thermal stability of the films were improved. The composite film exhibited antibacterial activity against food-borne pathogens. Results from this research indicated the potential of the genipin-crosslinked chitosan/VCF composites for applications in antimicrobial packaging. 


2010 ◽  
Vol 120 (3) ◽  
pp. 1671-1678 ◽  
Author(s):  
Devrim Balköse ◽  
Kaan Oguz ◽  
Lutfi Ozyuzer ◽  
Suleyman Tari ◽  
Esen Arkis ◽  
...  

2013 ◽  
Vol 469 ◽  
pp. 156-161 ◽  
Author(s):  
Hong Pan ◽  
Dan Xu ◽  
Qin Liu ◽  
Hui Qing Ren ◽  
Min Zhou

Starch-based nanocomposite films were fabricated by the incorporation of different amounts of nanodiamond (ND) particles. These films were characterized by SEM, FT-IR, TGA, tensile testing and water vapor permeability measurement. It was observed that at low loadings, ND dispersed well in starch matrix. However, as the loading amount increased, aggregates as large as several micrometers appeared. The physical blending of ND with starch didnt change the thermal degradation mechanisms of starch films, only increased the char residues. As the ND loading increased, the tensile strength of composite films increased but the elongation at break decreased. However, the water vapor permeability increased as the loading of ND increased due to the increased microspores in films. With further modifications, ND may be considered as a novel of biocompatible nanofillers for reinforcement of biopolymers for food packaging applications.


2010 ◽  
Vol 150-151 ◽  
pp. 1396-1399 ◽  
Author(s):  
Xi Hong Li ◽  
Kuan Guo ◽  
Xiao Yan Zhao

This paper explains and demonstrates the effects of beeswax on functional and structural properties of soy protein isolate films, containing different glycerol. The results showed that percentage elongation at break, water vapor permeability, and transparency of soy protein isolate films decreased when the beeswax content increased, but tensile strength and oxygen permeability increased. The higher the glycerol content, the higher the film water vapor permeability, oxygen permeability, and transparency. The results of differential scanning calorimetry and Fourier transform infrared spectroscopy suggested that beeswax cross-linked with soy protein isolate molecules via connecting with glycerol, composed the film matrix.


Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4406
Author(s):  
Anita Kwaśniewska ◽  
Michał Świetlicki ◽  
Adam Prószyński ◽  
Grzegorz Gładyszewski

In the present study, starch/powdered activated carbon composite films were prepared by incorporating various amounts of powdered activated carbon (PAC)—1–5, 10, and 15 %—into a starch matrix, using the solvent casting method. The effect of PAC addition on the biopolymer film was investigated. The mechanical properties were examined by ultra-nanoindentation, nanoscratch, and micro-tensile tests. Since the mechanical properties of biopolymer films are correlated with their structure, the effect of PAC addition was tested using X-ray diffraction. The surface parameters morphology and wettability were analyzed by atomic force microscopy (AFM) and contact angle measurements. The barrier properties were examined by determining water vapor permeability and the water solubility index. The obtained results did not show a monotonic dependence of the mechanical parameters on PAC content, with the exception of the maximum strain, which decreased as the amount of the additive increased. The visible effect of PAC addition was manifested in changes in the adhesive force value and in water vapor permeability (WVP). The barrier properties decreased with the increase of the filler content.


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