Pub Date : 2022-01-01DOI: 10.1590/0104-1428.20220042
M. Kondo, L. Montagna, G. F. Morgado, André Luiz Guimarães de Castilho, Larissa Anne Pereira dos Santos Batista, E. C. Botelho, M. L. Costa, F. R. Passador, M. C. Rezende, Marcos Valério Ribeiro
{"title":"Recent advances in the use of Polyamide-based materials for the automotive industry","authors":"M. Kondo, L. Montagna, G. F. Morgado, André Luiz Guimarães de Castilho, Larissa Anne Pereira dos Santos Batista, E. C. Botelho, M. L. Costa, F. R. Passador, M. C. Rezende, Marcos Valério Ribeiro","doi":"10.1590/0104-1428.20220042","DOIUrl":"https://doi.org/10.1590/0104-1428.20220042","url":null,"abstract":"","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67122094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/0104-1428.20220077
G. A. Carpenedo, N. B. Guerra, M. Giovanela, M. Paoli, J. S. Crespo
{"title":"Evaluation of lignin as stabilizer in vulcanized natural rubber formulations","authors":"G. A. Carpenedo, N. B. Guerra, M. Giovanela, M. Paoli, J. S. Crespo","doi":"10.1590/0104-1428.20220077","DOIUrl":"https://doi.org/10.1590/0104-1428.20220077","url":null,"abstract":"","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67122141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/0104-1428.210018
F. Lima, Luis Felipe Matos, Isnayra Kerolaynne Carneiro Pacheco, F. Reis, J. Câmara, J. Pierote, José Milton Matos, Alessandra A. Ribeiro, W. Moura, Ana Cristina Fialho
e Química Fina, Universidade Católica Portuguesa, Porto, Portugal *jvfrazao92@hotmail.com Obstract To analyze the biocompatibility of the scaffold produced from a natural polymer derived from castor oil through hemolytic activity and antimicrobial activity, to enable the clinical application. Three in vitro tests were performed: Hemolytic activity test - Polymer partially dissolved in contact with blood agar; Hemolytic activity test in sheep’s blood - Polymer extract with red blood cells solution; Antimicrobial activity test - Solid polymer in direct contact with E. Coli and S. Aureus. For hemolytic tests, none of the samples showed hemolysis. Negative hemolytic activity is a good indicator, as the maintenance of the blood clot in the area of the lesion is essential for the formation of new tissue. For the antimicrobial activity test, no significant activity was observed against the bacteria used. The polymer is not toxic to red blood cells, being
e Química Fina, Universidade Católica portuesa, Porto, Portugal *jvfrazao92@hotmail.com摘要通过对蓖麻油衍生的天然聚合物制备的支架的溶血活性和抗菌活性进行生物相容性分析，为其临床应用奠定基础。进行了三项体外试验:溶血活性试验——与血琼脂接触部分溶解的聚合物;绵羊血液溶血活性试验。红细胞溶液聚合物提取物抗菌活性试验-与大肠杆菌和金黄色葡萄球菌直接接触的固体聚合物。对于溶血试验，没有样品显示溶血。阴性溶血活性是一个很好的指标，因为维持病变区域的血凝块对新组织的形成至关重要。对于抗菌活性试验，没有观察到对所用细菌的显著活性。这种聚合物对红细胞没有毒性，因为
{"title":"Scaffold based on castor oil as an osteoconductive matrix in bone repair: biocompatibility analysis","authors":"F. Lima, Luis Felipe Matos, Isnayra Kerolaynne Carneiro Pacheco, F. Reis, J. Câmara, J. Pierote, José Milton Matos, Alessandra A. Ribeiro, W. Moura, Ana Cristina Fialho","doi":"10.1590/0104-1428.210018","DOIUrl":"https://doi.org/10.1590/0104-1428.210018","url":null,"abstract":"e Química Fina, Universidade Católica Portuguesa, Porto, Portugal *jvfrazao92@hotmail.com Obstract To analyze the biocompatibility of the scaffold produced from a natural polymer derived from castor oil through hemolytic activity and antimicrobial activity, to enable the clinical application. Three in vitro tests were performed: Hemolytic activity test - Polymer partially dissolved in contact with blood agar; Hemolytic activity test in sheep’s blood - Polymer extract with red blood cells solution; Antimicrobial activity test - Solid polymer in direct contact with E. Coli and S. Aureus. For hemolytic tests, none of the samples showed hemolysis. Negative hemolytic activity is a good indicator, as the maintenance of the blood clot in the area of the lesion is essential for the formation of new tissue. For the antimicrobial activity test, no significant activity was observed against the bacteria used. The polymer is not toxic to red blood cells, being","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"79 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67124663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/0104-1428.20220029
Alan Kardec da Silva, E. C. C. Torquato, Jacira Aparecida Castanharo, M. A. S. Costa, M. Marques, L. C. Costa
{"title":"Evaluation of magnetic poly(methyl methacrylate) microspheres as catalysts in heterogeneous Fenton processes","authors":"Alan Kardec da Silva, E. C. C. Torquato, Jacira Aparecida Castanharo, M. A. S. Costa, M. Marques, L. C. Costa","doi":"10.1590/0104-1428.20220029","DOIUrl":"https://doi.org/10.1590/0104-1428.20220029","url":null,"abstract":"","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67121504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/0104-1428.20220031
G. N. Campos, A. R. Coimbra, A. A. Silva, E. V. D. Rocha, F. N. Linhares, C. Furtado, A. M. F. Sousa
{"title":"Cross-link density measurement of nitrile rubber vulcanizates using dynamic shear test","authors":"G. N. Campos, A. R. Coimbra, A. A. Silva, E. V. D. Rocha, F. N. Linhares, C. Furtado, A. M. F. Sousa","doi":"10.1590/0104-1428.20220031","DOIUrl":"https://doi.org/10.1590/0104-1428.20220031","url":null,"abstract":"","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67121535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1590/0104-1428.20210066
A. Leite, Hamille Viotto, T. Nunes, D. Pasquini, A. Pero
{"title":"Cellulose nanocrystals into Poly(ethyl methacrylate) used for dental application","authors":"A. Leite, Hamille Viotto, T. Nunes, D. Pasquini, A. Pero","doi":"10.1590/0104-1428.20210066","DOIUrl":"https://doi.org/10.1590/0104-1428.20210066","url":null,"abstract":"","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67121347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Juliana Cristina Kreutz, P. R. Souza, Viviane Prima Benetti, A. Freitas, P. Bittencourt, L. Gaffo
Abstract Virgin polystyrene (PS) composites were reinforced with medium density fiberboard (MDF) residue, considering the influence of fiber content. The composites were evaluated for their morphology, identification of functional groups and thermal behavior. Mechanical tests and a degradation study under ultraviolet radiation (UV) were also performed. The results showed that the best properties were obtained for composites with 4% by mass of MDF waste. The addition of residue was found to increase thermal stability of polystyrene compared to its pure form. The morphology of the composites showed homogeneity of the material. In the degradation tests under ultraviolet (UV) radiation, it was found that the presence of MDF residue slows down the matrix degradation process when evaluated by means of tensile strength. Polystyrene composites reinforced with MDF residues showed good mechanical properties and can be applied in the development of materials that do not need a good appearance.
{"title":"Mechanical and thermal properties of polystyrene and medium density fiberboard composites","authors":"Juliana Cristina Kreutz, P. R. Souza, Viviane Prima Benetti, A. Freitas, P. Bittencourt, L. Gaffo","doi":"10.1590/0104-1428.07120","DOIUrl":"https://doi.org/10.1590/0104-1428.07120","url":null,"abstract":"Abstract Virgin polystyrene (PS) composites were reinforced with medium density fiberboard (MDF) residue, considering the influence of fiber content. The composites were evaluated for their morphology, identification of functional groups and thermal behavior. Mechanical tests and a degradation study under ultraviolet radiation (UV) were also performed. The results showed that the best properties were obtained for composites with 4% by mass of MDF waste. The addition of residue was found to increase thermal stability of polystyrene compared to its pure form. The morphology of the composites showed homogeneity of the material. In the degradation tests under ultraviolet (UV) radiation, it was found that the presence of MDF residue slows down the matrix degradation process when evaluated by means of tensile strength. Polystyrene composites reinforced with MDF residues showed good mechanical properties and can be applied in the development of materials that do not need a good appearance.","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45895779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. D. C. D. Almeida, João Paulo Teixeira da Silva, Felipe Fernando da Costa Tavares, Ludmila Leite Araujo, Jefferson de Souza Zeferino, R. Santana
Abstract In this work, a bio-based adhesive is prepared from Protium heptaphyllum resin. The resin is first characterized by 1H and 13C nuclear magnetic resonance spectroscopy and the bioadhesive is then prepared using a simple mixture of the resin with linseed oil, catalyzed by cobalt octanoate, to induce crosslinking. The precursors and bioadhesive obtained are characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The NMR analysis shows the presence of groups of triterpenes, such as α- and β-amyrins, and diols, such as brein and maniladiol. Thermogravimetric analysis reveals that the resin has less thermal stability than the bioadhesive. Mechanical tests indicate that the bioadhesive has greater adhesion strength compared to the commercial adhesive, reaching an average stress at break of 7.66 and 0.113 MPa for the wood and carbon steel substrates, respectively. In conclusion, the bioadhesive can be used for the production of composites.
{"title":"Development of a bio-based adhesive from Protium heptaphyllum resin","authors":"M. D. C. D. Almeida, João Paulo Teixeira da Silva, Felipe Fernando da Costa Tavares, Ludmila Leite Araujo, Jefferson de Souza Zeferino, R. Santana","doi":"10.1590/0104-1428.10020","DOIUrl":"https://doi.org/10.1590/0104-1428.10020","url":null,"abstract":"Abstract In this work, a bio-based adhesive is prepared from Protium heptaphyllum resin. The resin is first characterized by 1H and 13C nuclear magnetic resonance spectroscopy and the bioadhesive is then prepared using a simple mixture of the resin with linseed oil, catalyzed by cobalt octanoate, to induce crosslinking. The precursors and bioadhesive obtained are characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The NMR analysis shows the presence of groups of triterpenes, such as α- and β-amyrins, and diols, such as brein and maniladiol. Thermogravimetric analysis reveals that the resin has less thermal stability than the bioadhesive. Mechanical tests indicate that the bioadhesive has greater adhesion strength compared to the commercial adhesive, reaching an average stress at break of 7.66 and 0.113 MPa for the wood and carbon steel substrates, respectively. In conclusion, the bioadhesive can be used for the production of composites.","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46001804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This study aimed to evaluate the process of cellulose extraction from yacon stem using combined pulping and bleaching processes to produce nanofibrillated cellulose (NFC). First, a chemical pulping process with NaOH was applied and, subsequently, the pulp obtained was bleached. From the chemical pulp (CP) bleached, NFC was obtained by the mechanical defibrillation in a colloidal grinder. Then, chemical composition, and infrared analysis of the pulps were performed. The pulping process showed a lower amount of extractives and lignin content, as a low yield and an excessively dark pulp. The CP bleached with NaClO2 showed the best results increased whiteness of the pulp. A suspension of NFC with fibers of 5-60 nm in diameter, high crystallinity index, and thermal stability was obtained. The results are promising and demonstrate the technical feasibility of obtaining NFC from yacon stems waste which is ideal to apply to other materials of the industry.
{"title":"Extraction and characterization of nanofibrillated cellulose from yacon plant (Smallanthus sonchifolius) stems","authors":"R. S. D. Sousa, A. S. D. Andrade, M. L. Masson","doi":"10.1590/0104-1428.09620","DOIUrl":"https://doi.org/10.1590/0104-1428.09620","url":null,"abstract":"Abstract This study aimed to evaluate the process of cellulose extraction from yacon stem using combined pulping and bleaching processes to produce nanofibrillated cellulose (NFC). First, a chemical pulping process with NaOH was applied and, subsequently, the pulp obtained was bleached. From the chemical pulp (CP) bleached, NFC was obtained by the mechanical defibrillation in a colloidal grinder. Then, chemical composition, and infrared analysis of the pulps were performed. The pulping process showed a lower amount of extractives and lignin content, as a low yield and an excessively dark pulp. The CP bleached with NaClO2 showed the best results increased whiteness of the pulp. A suspension of NFC with fibers of 5-60 nm in diameter, high crystallinity index, and thermal stability was obtained. The results are promising and demonstrate the technical feasibility of obtaining NFC from yacon stems waste which is ideal to apply to other materials of the industry.","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41446477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Flexible transparent substrate materials, which was able to withstand high dynamic strain, in contrast to traditional substrate materials. A flexible and transparent material with advantages including transparency, stable size, and excellent corrosion and electrical resistance was provided. The polyimide(PI) film was prepared by introducing a structure with a high content of F atom and a fine optimization process to enhance the various properties of the film. However, the properties of the films were optimized effectively by gradient vacuum and secondary dissolution so that the film had a transmittance at 400 nm of 82%. The films with low dielectric constant and low dielectric loss represent the breakdown strength of 202 kV/mm. The glass transition temperature of the film was 267 °C, and the thermal expansion coefficient was 35ppm/k (30 °C~270 °C), indicated outstanding thermal dimensional stability. Therefore, this polyimide film was an optoelectronic device with extremely high application potential on the folding mobile phone and the PI film is the finest materials of screen.
{"title":"A foldable high transparent fluorinated polyimide (HFBAPP/6FDA) film material for transparent flexible substrate","authors":"Chuanhao Cao, Lizhu Liu, Xiaorui Zhang","doi":"10.1590/0104-1428.10520","DOIUrl":"https://doi.org/10.1590/0104-1428.10520","url":null,"abstract":"Abstract Flexible transparent substrate materials, which was able to withstand high dynamic strain, in contrast to traditional substrate materials. A flexible and transparent material with advantages including transparency, stable size, and excellent corrosion and electrical resistance was provided. The polyimide(PI) film was prepared by introducing a structure with a high content of F atom and a fine optimization process to enhance the various properties of the film. However, the properties of the films were optimized effectively by gradient vacuum and secondary dissolution so that the film had a transmittance at 400 nm of 82%. The films with low dielectric constant and low dielectric loss represent the breakdown strength of 202 kV/mm. The glass transition temperature of the film was 267 °C, and the thermal expansion coefficient was 35ppm/k (30 °C~270 °C), indicated outstanding thermal dimensional stability. Therefore, this polyimide film was an optoelectronic device with extremely high application potential on the folding mobile phone and the PI film is the finest materials of screen.","PeriodicalId":20282,"journal":{"name":"Polimeros-ciencia E Tecnologia","volume":"121 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73217585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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