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1.
The release of extractables from multi‐layered plastic films such as those used in containers for liquid drug products has been investigated. Targeted extractables were chosen from the film's extractable profile, as elucidated by a controlled extraction study. The total available pool of targeted extractables was ascertained via exhaustive sequential extraction of the film and the film layer responsible for the target extractables was established. This information, along with the film's structure, was used to produce a mathematical migration model for each of these targets. The film was fashioned into pouches, filled with a simulating solvent and the release of the targeted extractables to the pouches' contents was measured. The measured and modeled concentrations were found to be very similar, establishing the model's ability to effectively mimic the experimental system. This result suggests that mathematical modeling, which is widely used in the food industry to assess the safety of food packaging, may be applicable to packaged pharmaceutical products. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41223.  相似文献   

2.
In this study, we synthesized novel films based on bacterial cellulose (BC), BC modified by polypyrrole (PPy), and a PPy–zinc oxide nanocomposite (BC–PPy–ZnO). The soft polymerization method at room temperature was used to obtain the BC–PPy and BC–PPy–ZnO films. The Combined D‐Optimal design was used to study the effects of the pyrrole monomer concentration, ZnO concentration, and polymerization time on the morphological, physical, color, and electrical conductivity properties of the films. Fourier transform infrared results reflected that some new interactions occurred between BC and PPy and PPy–ZnO. The X‐ray diffraction analysis showed that the crystalline behavior of the BC fiber was hindered because of the complete coating with the amorphous PPy particles. Scanning electron microscopy results show that the ZnO, PPy, and PPy–ZnO nanoparticles were placed between the BC fibers. PPy decreased the water vapor permittivity and total soluble matter percentage. Electrical conductivity studies of the synthesized BC–PPy–ZnO film showed that the film's electrical resistance was changed in different oxidation–reduction or volatile compounds media, so the results suggest that the BC–PPy–ZnO films could be used in antioxidative food active packaging and smart packaging. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46617.  相似文献   

3.
In this study, a novel film structure of corn zein coated on polypropylene (PP) synthetic films for food packaging applications was developed, and the mechanical properties of the resulting coated film, as affected by the coating formulation, were investigated. Composite structures of PP films coated with corn zein were obtained through a simple solvent casting method. Different amounts of corn zein (5 and 15%) were dissolved in 70 and 95% aqueous ethanol solution at 50°C. Solutions of corn zein plasticized with poly(ethylene glycol) and glycerol (GLY) at various levels (20 and 50%) were applied on corona‐discharge‐treated PP. A statistical analysis based on full factorial design was performed to examine the influence of the coating formulation on the final properties of the corn‐zein‐coated PP films. A significant (p < 0.05) improvement in the coated film's mechanical properties was observed compared to those of the uncoated PP. The effect of the plasticization of the coating solutions was also quite significant. In general, GLY provided better improvements in the mechanical properties of the corn‐zein‐coated PP films. The statistical analysis of the results showed that the corn‐zein and plasticizer concentrations and plasticizer type used in the coating formulations were more effective parameters and had significant effects on the mechanical behavior of the coated PP films. In conclusion, corn‐zein coatings could have potential as alternatives to conventional synthetic polymers used in composite multilayer structures for food packaging applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

4.
Hydroxypropyltrimethylammonium chloride cellulose (CM) was homogeneously synthesized in a NaOH/urea aqueous solution. CM was blended in a polyvinyl alcohol (PVA) matrix to produce composite films via co‐regeneration from the alkaline solution. The PVA film and the blend films were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction measurements and scanning electron microscopy. The mechanical properties, water swelling ratio, hydrophobicity, light transmission, and antibacterial activity against Staphylococcus aureus and Escherichia coli were also evaluated. The results showed that CM could interact with PVA by hydrogen bonding and exhibit an obvious reinforcement effect. The addition of CM improved the surface roughness, hydrophobicity and water swelling ratio, especially, the antibacterial activity. However, compared with neat PVA film, the elasticity and optical transmission decreased. The increased tensile strength, powerful antibacterial activity, and medium light transmission indicate that the biocompatible blend film will become an exceptional alternative in functional bio‐material field. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43552.  相似文献   

5.
Food quality and safety are major concerns in the food industry. Antimicrobial packaging can be considered an emerging technology that could have a significant impact on life and food safety. Antimicrobial agents in food packaging can control the microbial population and target specific microorganisms to provide greater safety and higher quality products. In this work, a lactic acid grafted chitosan film was synthesized. Silver nanoparticles were loaded into the chitosan lactate (CL) film by equilibration in a silver nitrate solution, which was followed by citrate reduction. The presence of silver nanoparticles was confirmed with transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis of the film. The silver‐nanoparticle‐loaded CL film was investigated for its antimicrobial properties against Escherichia coli. This newly developed material showed strong antibacterial properties and thus has potential for use as an antibacterial food‐packaging material. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

6.
Crosslinked nanocomposite films of sodium alginate (SA) and silicon dioxide (SiO2) with different SiO2 loading values were prepared by in situ synthesis. Biocomposite films were produced by solution casting and solvent evaporation with glycerol as the plasticizer and calcium chloride as the crosslinking agent. The effects of the addition of nano silicon dioxide (nano‐SiO2) in SA on the microstructural, physical, mechanical, and optical properties of the nanocomposite films were characterized. The results show that nano‐SiO2 was dispersed homogeneously in the SA matrix; it thereby formed a strong interfacial interaction between the nano‐SiO2 particles and the matrix. The transparency of the bionanocomposite films was enhanced. Thermogravimetric analysis also revealed that nano‐SiO2 improved the thermal stability of the SA films. The incorporation of SiO2 further reduced the water vapor permeability and swelling degree and significantly increased the tensile strength and elongation, which are parameters important for packaging industries. Finally, the lower light transmission of UV light from 200 to 250 nm indicated that SA/SiO2 nanocomposite films could potentially be used to prevent lipid damage by UV light in food conservation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43489.  相似文献   

7.
The packaging industry is searching for alternative materials to attain environmental sustainability. Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate (PHBV) is a semicrystalline polymer that meets this sustainability goal since it is bioderived and biodegradable. However, its brittle nature and relatively high water permeation and transmission rates make it unsuitable for packaging applications. In addition, PHBV has poor mechanical, thermal, and rheological properties above 160 °C, limiting its use in cast sheets and thermo‐formed packaging applications. To improve these properties, new blends of PHBV with high molecular weight natural rubber at 5, 10, 15, and 25% by weight were fabricated, and physico‐chemical properties of the blends were characterized. The rubber in the blends aided in the following: increased thermal stability since the complex viscosities of the blends were improved by one log over pure PHBV at 170 °C, created more uniform melting peaks attesting to improved homogeneity, decreased water permeation to a level similar to that of traditional thermoplastics; increased the elongation at break, and stabilized the Young's modulus. Therefore, these blends can potentially be used in‐place of traditional, petroleum‐based thermoplastics in cast sheets and thermoforms. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43937.  相似文献   

8.
In this research, cellulose nanocrystals (CNs) were extracted from corn cobs by 2,2,6,6,‐tetramethylpiperidine‐1‐oxyl radical‐mediated oxidation combined with ultrasonic treatment for the first time. These CNs were then used as a mechanical reinforcement agent and barrier in chitosan‐based bionanocomposite films. Birefringence analyses under crossed polarizers indicated the presence of isolated nanocrystals in suspension, which was later confirmed by TEM analysis. The crystallinity index obtained from X‐ray diffraction was 92.4%. The incorporation of these nanoparticles into a filmogenic matrix of chitosan made it possible to obtain bionanocomposite films with improved properties. The water‐vapor permeability was reduced by 70%, whereas the tensile strength and Young's modulus increased by up to 136 and 224% respectively. The developed films were applied as interleaving of sliced cheese, and the efficiency was assessed by investigation of adhesion between the surfaces and by comparing its properties with two commercial interleaving products (polyethylene (PE), and Greasepel paper (GP)). Concluding, the developed films showed a substantial potential to be exploited as an interleaving film, owing to its excellent mechanical properties, permeability, hydrophobicity, and low surface adhesion compared to pure chitosan, PE, and GP films. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43033.  相似文献   

9.
Speciality high‐strength board, packaging grades, and novel cellulose‐based nanocomposites may incorporate microcellulosic nanofibrillated materials (MNFC), although the rheological properties of such strongly water sorbing structures are challenging for processing technologies. This study introduces rheological methods for the evaluation of dewatering and flow behavior of such high consistency furnishes to exemplify the effect of energy input on microfibrillar material (MFC), as produced by a combination of enzymatic pretreatment and increased levels of fluidization. The large number of fibril contact points act to entrap water, held both on the fibril surface as immobilized water and in the interfibril spacing forming the gel structure. Tuning of the rheological and dewatering properties has been enabled by in situ precipitation of calcium carbonate filler (in situ PCC) on the MFC, which results in the production of a more uniform furnish. Such in situ PCC coated MFC fibrils incorporated into furnish were seen to increase dewatering rate over that of the furnish mix without the in situ precipitated filler primarily because of the reduction in total surface area of the fibers and fibrils when the pigment is present on the fibrillary surface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43486.  相似文献   

10.
In this study, interaction and compatibility between sugar‐beet pulp (SBP) and polyvinyl alcohol (PVA) in blend films was assessed. Film‐forming dispersions of different ratios of SBP to PVA (100/0, 75/25, 50/50, and 25/75) were cast at room temperature. The effects of adding PVA to SBP on the resulting film's physical, mechanical and barrier properties and thermal stability were investigated. X‐ray diffraction and environmental scanning electron microscopy (ESEM) were used to characterize the structure and morphology of the composites. When PVA was also added to the composite films, the films became softer, less rigid and more stretchable than pure SBP films. The addition of PVA gave significantly greater elongation at break (12.45%) and lower water vapor permeability (1.55 × 10?10 g s?1 m?1 Pa?1), but tensile strength did not markedly change, remaining around 59.68 MPa. Thermogravimetric analysis also showed that SBP/PVA film had better thermal stability than SBP film. The ESEM results showed that the compatibility of SBP50/PVA50 was better than those of other composite films. These results suggest that when taking all the studied variables into account, composite films formulated with 50% PVA are most suitable for various packaging applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41354.  相似文献   

11.
Active and biodegradable materials have great potential in food packaging applications, improving the safety and quality of products. The objective of this study was to develop a new material based on buriti oil incorporated into a chitosan film. Different concentrations of buriti oil in dried films (2.1 g/m2, 10.4 g/m2, 20.8 g/m2, and 31.3 g/m2) were added into a chitosan matrix (41.7 g/m2). The chitosan/buriti oil films were characterized by water‐vapor barrier properties, total water‐soluble matter (TSM), tensile properties, thermogravimetric analysis, microstructure, microbial permeation properties, and biodegradation estimation. The higher oil concentration improved the water‐vapor barrier and the buriti oil acted largely as a plasticizer and increased the elongation at break, and decreased the tensile strength (TS) of chitosan films. The total water‐soluble matter of chitosan films decreased in function of the buriti oil concentration, but the biodegradation and thermal stability increased. The chitosan films presented a microbial barrier against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43210.  相似文献   

12.
Modification of low‐density polyethylene (LDPE) with vanillin to obtain flavored packaging film with improved gas barrier and flavor‐releasing properties has been studied. The modification of LDPE with vanillin was monitored by Fourier transform infrared spectroscopy, wherein the appearance of new peaks at 1704.7, 1673.6, and 1597.2 cm?1 indicates the incorporation of vanillin into LDPE matrix. Films of uniform thickness were obtained by the extrusion of modified LDPE. Modified LDPE was found to have significantly higher gas barrier properties and grease resistance. Sensory quality of food products viz, doodhpeda (milk‐based solid soft sweet), biscuit, and skimmed milk powder packed in LDPE‐vanillin film showed that the doodhpeda sample had clearly perceptible vanilla aroma, whereas biscuit had marginal aroma and skimmed milk powder did not have noticeable aroma. When viewed in the light of imparting desirable vanilla aroma, results of the study indicated that LDPE‐vanillin film has better prospects as a packaging material for solid sweets with considerable fat content when stored under ambient conditions. The release of vanilla aroma was further confirmed by gas chromatography–mass spectrometery analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

13.
To explore the effect of short glass fiber reinforcement (SGFR) on the mechanical properties of polyethersulfone (PES), microstructural characterization has been performed by positron lifetime technique. The free volume distribution of SGFR‐PES composites derived from CONTIN‐PALS2 program exhibits the narrow full width at half maximum (FWHM) indicates the strong interaction between polymeric chains of PES matrix and SGF. The positron lifetime parameters of SGFR‐PES composites are correlated with the mechanical properties viz., Tensile strength (TS), Young's modulus (YM) and elongation at break (EB). The decreased positron lifetime parameters, improved mechanical properties and reduced crystallinity of SGFR‐PES composites are attributed to the improved chemical and physical interaction between the functional groups of both SGF and PES matrix. This is clearly evident from the FTIR (Fourier Transform Infrared Spectrometry) studies. The hydrodynamic interaction parameter (h) show negative values, suggest the improved interaction in SGFR‐PES composites by the generation of excess friction at the interface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43647.  相似文献   

14.
In this study, a smart biodegradable film based on wheat gluten modified with chlorophyll (WG/Ch) is presented. The effect of chlorophyll on the antioxidant activity and mechanical properties of WG/Ch film is studied. Scanning electron microscopy and Fourier‐transform infrared spectroscopy (FT‐IR) analyses are used to study the structure and chemical composition of gluten‐based films. The WG/Ch film is used in the packaging of sesame oil. The effect of WG/Ch film on increasing the shelf life and detecting expiration time of oil is studied. FT‐IR results show that weak interactions are created between gluten and chlorophyll. The antioxidant activity of the WG film is 60% and it increases to 85% by the addition of chlorophyll. The results show that with the increasing storage time of oil samples, oxidative indices are increased, but the WG/Ch film decreases the sesame oil oxidation significantly (almost in the all oxidative indices 50% decrease is observed). Practical Applications: The WG/Ch film is used in the packaging of sesame oil. The effect of WG/Ch film on the increasing of shelf life and detecting expiration time of oil is studied. By increasing storage time and oxidant, acidity, acid number, PA, and oil color change are increased, but the WG/Ch active film decreases the sesame oil oxidation significantly. Also, by examining the color properties of the active film, it is observed that with increasing storage time and oxidant percent, the color of the film is changed (from green to yellow), which can be used to estimate the oil expiration time. It should be mentioned that the film's color changes are visible to the naked eye.  相似文献   

15.
Starch-based biodegradable films were prepared by using solution-casting method and reinforced by agricultural residues [apricot and walnut shell (APS and WNS) powder]. The powder of both shells was added in different ratios (0, 2.5, 5, 7.5, and 10%) to investigate the microstructures and performances (mechanical and thermal properties) of the starch-based film. Different techniques such as impact, tensile testing, scanning electron microscope, optical microscope (OM), X-ray diffraction (XRD), water vapor transmission rate (WVTR), and dynamic mechanical analysis were applied to study the thermomechanical and barrier properties of the composite films. Results showed that the incorporation of both shells significantly improved the WVTR and mechanical properties of starch-based films. The shells powder was significantly increased the Young's modulus and tensile strength of the starch-based films. Both OM and SEM results showed reasonably good compatibility between starch and reinforced shells. OM and XRD indicated that the APS and WNS not only retained their crystalline structure in the film but they also strengthened the peak intensity of the film. This phenomenon can be used to explain the mechanism of mechanical reinforcement. Since all the components used in the preparation of the films are food grade ingredients, it is expected that the films developed in this work will be used for food packaging applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47978.  相似文献   

16.
Polycaprolactone (PCL) and polyglycolide (PGA) are two biopolymers that have been used as in situ biomedical devices for various applications. The obstacle of creating a composite that captures the benefit of PCL's long degradation time, while acquiring the strength from PGA is overcoming the lack of surface adhesion between the two biopolymers for stress transfer to occur. This study investigates the use of miscible PCL‐PGA blended fibers, created by electrospinning, to increase the interfacial bonding of fibers to the PCL matrix of the polymer–polymer composite. The use of the blended fibers will thereby create the ability of load transfer from the long‐term PCL matrix to the stronger PCL‐PGA fiber reinforcement. The incorporation of the PCL‐PGA fibers was able to increase the tensile yield strength and Young's modulus over that of the bulk PCL, while decreasing the percent elongation at break. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40224.  相似文献   

17.
Antibacterial polycaprolactone (PCL) electrospun fiber mats were prepared by coelectrospinning PCL with soluble eggshell membrane protein (SEP) in 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP), followed by adsorption of silver nanoparticles (Ag NPs) through hydrogen‐bonding interaction between the amide groups of SEP and the carboxylic acid groups capped on the surfaces of Ag NPs. The PCL/SEP fiber mat was characterized by X‐ray photoelectron spectroscopy, indicating the presence of some SEP on the fiber surface. The adsorption of Ag NPs was confirmed by transmission electron microscopy and quantitatively characterized by thermogravimetric analysis. The pH value of the silver sol used for adsorption is very important in view of the amount and dispersion state of Ag NPs adsorbed on the fibers. The Ag NP–decorated PCL/SEP fiber mats prepared at pH 3–5 exhibit strong antibacterial activity against both gram‐negative Escherichia coli and gram‐positive Bacillus subtilis. Antibacterial PCL fiber mats were also obtained similarly with the assistance of collagen (another protein) instead of SEP, showing that protein‐assisted adsorption of Ag NPs is a versatile method to prepare antibacterial electrospun fiber mats. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43850.  相似文献   

18.
For the application of single‐layer food packaging films with improved barrier properties, an attempt was made to prepare ethylene‐vinyl alcohol (EVOH) copolymer‐based nanocomposite films by incorporation of organically modified montmorillonite nanoclays via a two‐step mixing process and solvent cast method. The highly intercalated tactoids coexisted with exfoliated clay nanosheets, and the extent of intercalation and exfoliation depended significantly on the level of clay loadings, which were confirmed from both XRD measurements and TEM observations. It was revealed that the inclusion of nanoclay up to an appropriate level of content resulted in a remarkable enhancement in the thermal, mechanical (tensile strength/modulus), optical, and barrier properties of the prepared EVOH/clay nanocomposite films. However, excess clay loadings gave rise to a reduction in the tensile properties (strength/modulus/elongation) and optical transparency due to the formation of clay tactoids with a larger domain size. With the addition of only 3 wt % clay, the oxygen and water vapor barrier performances of the nanocomposite films were substantially improved by 59 and 90%, respectively, compared to the performances of the neat EVOH film. In addition, the presence of clay nanosheets in the EVOH matrix was found to significantly suppress the moisture‐derived deterioration in the oxygen barrier performance, implying the feasibility of applying the nanocomposite films to single‐layer food packaging films. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40289.  相似文献   

19.
In this study, low‐density polyethylene (LDPE) nanocomposite films with two types of nanoparticles, TiO2 (3 wt %) and Closite 20A (3 and 5 wt %), were prepared using a melt blow extrusion as an industrial method and their properties such as mechanical properties, water vapor, oxygen and carbon dioxide gas barrier, and antimicrobial activity were tested. Transmission electron microscopy (TEM) and X‐ray diffraction (XRD) were also performed to determine the degree of dispersion and exfoliation of nanoparticles. Mechanical test indicated that the reinforcement in the presence of the nanocomposites was more than that with their conventional counterparts, and the highest stiffness was achieved in a sample containing 5 wt % clay and 3 wt % TiO2. Exfoliation of silicate layers and a good dispersion of TiO2 nanoparticles in LDPE were achieved as confirmed by XRD and TEM. The gas barrier properties were improved after formation of the nanocomposites especially by insertion of 5 wt % of clay nanoparticles as a filler in the LDPE matrix. The photocatalytic effect of the nanocomposite film was carried out by antimicrobial evaluation against Pseudomonas spp. and Rhodotorula mucilaginosa and by ethylene removal test using 8 W ultraviolet (UV) lamps with a constant relative intensity of 1 mW cm?2. The greatest effects were recorded by combining UVA illumination and active film. It was also proven that the photocatalyst thin film with improved barrier properties prepared by extrusion could be used in horticultural product packaging applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41764.  相似文献   

20.
The curing mechanism of an epoxy film containing dicyandiamide (DICY) and an epoxy formulation based on diglycidyl ether of Bisphenol A (DGEBA) polymer was studied as a function of various temperature programs. The investigation was performed in situ, using a thin film of the epoxy mixture on a silicon wafer substrate in a heatable transmission tool of a FTIR spectrometer. Based on these model‐curing experiments, a major curing mechanism was proposed, taking into account the appearance, the decrease, and the development of characteristic bands at various temperatures. The conclusions of the model curing were correlated to FTIR measurements on a real, 50‐mm‐thick glass fiber reinforced component composite part from a technical process. It could be shown that characteristic bands that develop at curing temperatures above 150°C appear especially in the center of the thick sample. From the chemical or molecular point of view, this demonstrates the established technician's understanding that temperature control inside a large‐scale fiber composite of, for example, aircraft, wind‐turbine, automotive applications component is of major importance. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39832.  相似文献   

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