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| Rotta,Jefferson; Minatti,Edson; Barreto,Pedro Luiz Manique. |
| In this work, the structural, mechanical, diffractometric, and thermal parameters of chitosan-hydroxypropylmethylcellulose (HPMC) films plasticized with sorbitol were studied. Solutions of HPMC (2% w/v) in water and chitosan (2% w/v) in 2% acetic acid solution were prepared. The concentration of sorbitol used was 10% (w/w) to both polymers. This solutions were mixed at different proportions (100/0; 70/30; 50/50; 30/70, and 0/100) of chitosan and HPMC, respectively, and 20 mL was cast in Petri dishes for further analysis of dried films. The miscibility of polymers was assessed by X-ray diffraction, scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The results obtained indicate that the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Films; Chitosan; Hydroxypropylmethylcellulose; Physico-chemical properties. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612011000200026 |
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| Lima,Isabela Angeli de; Pomin,Suelen Plaza; Cavalcanti,Osvaldo Albuquerque. |
| ABSTRACT Free films of pullulan-polymethacrylate associations were produced by casting process to develop a novel target-specific material. For characterization, tests of water vapor permeability, swelling index, infrared absorption spectroscopy, thermogravimetric analysis, scanning electron microscopy and mechanical analysis were performed. The polysaccharide concentration directly influenced vapor permeability and swelling, increasing the values of the latter up to five times when added in a proportion of 20% (per weight). The individual properties of each polymer were maintained, and chemical interactions were not detected. The films were found to be thermally stable and they had unaltered mechanical properties with the addition of the polysaccharide.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Films; Polymeric material; Modified release/enteric release/oral delivery/controlled release; Glucans; Eudragit; Physicochemical characterization. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502017000300601 |
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| SCHMIDT,Vivian Consuelo Reolon; BLANCO-PASCUAL,Nuria; TRIBUZI,Giustino; LAURINDO,João Borges. |
| Abstract The objective of this study was to develop films with reduced hygroscopicity and improved mechanical properties from acetylated cassava starch. For that, an acetylation procedure using acetic anhydride as the esterification reagent was performed, resulting in starch acetates with degrees of substitution (DS) of 0.6 (S0.6) and 1.1 (S1.1). Twelve films formulations were studied: native cassava starch (S), starch acetate S0.6 and S1.1, with two glycerol concentrations (0.25 g.100 g-1 (25) and 0.30 g.100 g-1 (30)). The films were conditioned at the relative humidities (RH) of 58% and 75% for 96 h before characterization. Water vapor permeability, water solubility, water sorption isotherms, microstructural analyses, and mechanical properties in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Films; Starch acetate; Biodegradable; Physical properties. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612019000200491 |
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| Bellini,Márcia Zilioli; Oliva-Neto,Pedro de; Moraes,Ângela Maria. |
| In this study, the effects of the origin of xanthan used, in combination with chitosan, to prepare films for the treatment of skin lesions were evaluated. The characteristics of the films obtained with xanthan commercially available for the food industry sector and xanthan originated from a fermentation process conducted in a pilot plant were compared. Results showed that the source did not strongly interfere in many of the properties of the films, such as the mechanical properties, cytotoxicity to L929 cells, absorption of simulated body fluid and culture medium, stability in water and saline solution. Hence, even though the properties of biopolymers of different sources might vary, the films prepared with two distinct types of xanthan gum could be... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biomaterials; Biopolymers; Films; Membranes; Properties and characterization; Biomedical applications. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132015000200289 |
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| MALAFATTI, J. O. D.; RUELLAS, T. M. O.; SCHILDT, L. F. L.; DOMINGUES, M. A.; MARINHO, B. S.; MEIRELLES, M. R.; PARIS, E. C.. |
| Filmes biodegradáveis vêm sendo estudados devido ao baixo impacto negativo ao meio ambiente em relação às poliolefinas, sendo possível o emprego em diversos campos, como embalagens, agricultura, farmácia, entre outros. Dentre esta classe de polímeros, o amido possui um grande destaque por ser um polissacarídeo de baixo custo proveniente de fontes renováveis, como milho, batata e mandioca. Todavia, filmes biodegradáveis de amido possuem um grande desafio de aplicação devido às propriedades degradativas intrínsecas. Para que a utilização comercial seja possível, a transformação do amido em amido termoplástico (TPS) é uma alternativa extremamente promissora, uma vez que garante as propriedades mecânicas necessárias ao filme após o processamento. O TPS é... |
| Tipo: Parte de livro |
Palavras-chave: Thermoplastic Starch; Films; Filmes biodegradáveis. |
| Ano: 2021 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1134436 |
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| Lameira,Rafaely das Chagas; Silva,Bárbara Marçon Pereira da; Valentini,Silvia Regina de Toledo; Cia,Patrícia; Bron,Ilana Urbano. |
| ABSTRACT: Despite the fact that cold storage and modified atmosphere techniques have already been studied for fresh cut Star fruit, little has been done considering the whole fruit. Besides that, each cultivar has its peculiarities, so the efficiency of combined postharvest treatments should be studied. The objective of this study was to evaluate the effect of polyvinyl chloride (PVC), 8.5 µm thick and low-density polyethylene (LDPE), 33 µm thick associated with cold storage (10 ± 1 °C and 5 ± 1 °C / 85 ± 5% RH) on the conservation of ‘Malasia’ Star fruit. Storage at 25 oC maintained Star fruit overall quality, regardless of the film type, up to four days. The weight loss was higher in fruit packed with PVC, but this fact was not noticed by the sensory... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Averrhoa carambola L.; Films; Postharvest; Ripening.. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000500203 |
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