{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T14:52:52Z","timestamp":1768834372310,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,3,6]],"date-time":"2024-03-06T00:00:00Z","timestamp":1709683200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Unit of Fiber Materials and Environmental Technologies (FibEnTech-UBI)","award":["UIDB\/00195\/2020"],"award-info":[{"award-number":["UIDB\/00195\/2020"]}]},{"name":"Research Unit of Fiber Materials and Environmental Technologies (FibEnTech-UBI)","award":["UIDB\/00151\/2020"],"award-info":[{"award-number":["UIDB\/00151\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, IP\/MCTES through national funds (PIDDAC)","award":["UIDB\/00195\/2020"],"award-info":[{"award-number":["UIDB\/00195\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, IP\/MCTES through national funds (PIDDAC)","award":["UIDB\/00151\/2020"],"award-info":[{"award-number":["UIDB\/00151\/2020"]}]},{"name":"Center for Mechanical and Aerospace Science and Technologies (C-MAST-UBI)","award":["UIDB\/00195\/2020"],"award-info":[{"award-number":["UIDB\/00195\/2020"]}]},{"name":"Center for Mechanical and Aerospace Science and Technologies (C-MAST-UBI)","award":["UIDB\/00151\/2020"],"award-info":[{"award-number":["UIDB\/00151\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, IP\/MCTES through national funds (PIDDAC)","award":["UIDB\/00195\/2020"],"award-info":[{"award-number":["UIDB\/00195\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, IP\/MCTES through national funds (PIDDAC)","award":["UIDB\/00151\/2020"],"award-info":[{"award-number":["UIDB\/00151\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The environmental emergency has alerted consumers and industries to choose products derived from renewable sources over petroleum derivatives. Natural fibers of plant origin for reinforcing composite materials dominate the field of research aiming to replace synthetic fibers. The field of application of green dog wool composite materials needs to be reinforced and proven, as the industry is looking for more sustainable solutions and on the other hand this type of raw material (pet grooming waste) tends to grow. Hence, in the present work, the feasibility of applying natural fibers of dog origin (mainly composed by keratin) in green composites was studied. The green composites were developed using chemically treated dog wool of the breed Serra da Estrela (with NaOH and PVA) as reinforcement and a green epoxy resin as a matrix. The chemical treatments aimed to improve adhesion between fibers and matrix. The fibers\u2019 composition was determined using X-ray Diffraction (X-RD). Their morphology was determined using a scanning electron microscope (SEM). The wettability of the fiber was also evaluated qualitatively by analyzing drops of resin placed on the fibers treated with the different treatments. The mechanical properties of the composites were also studied through mechanical tensile, flexural, and relaxation tests. Overall, the best results were obtained for the dog wool fibers without treatment. The tensile and flexural strength of this biocomposite were 11 MPa and 26.8 MPa, respectively, while the tensile and flexural elastic modulus were 555 MPa and 1100 MPa, respectively. It was also possible to verify that the PVA treatment caused degradation of the fiber, resulting in a decrease in mechanical tensile strength of approximately 42.7%, 59.7% in flexural strength and approximately 59% of the stress after 120 min of relaxation when compared to fiber made from untreated dog wool. On the other hand, the NaOH treatment worked as a fiber wash process, removing waxes and fats naturally present on the fiber surface.<\/jats:p>","DOI":"10.3390\/polym16050718","type":"journal-article","created":{"date-parts":[[2024,3,6]],"date-time":"2024-03-06T05:48:01Z","timestamp":1709704081000},"page":"718","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Viability Study of Serra da Estrela Dog Wool to Produce Green Composites"],"prefix":"10.3390","volume":"16","author":[{"given":"Alexandra Soledade","family":"Gomes","sequence":"first","affiliation":[{"name":"Fiber Materials and Environmental Technologies Research Unit (FibEnTech-UBI), Universidade da Beira Interior, Rua Marqu\u00eas D\u2019\u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7374-3636","authenticated-orcid":false,"given":"Paulo Torr\u00e3o","family":"Fiadeiro","sequence":"additional","affiliation":[{"name":"Fiber Materials and Environmental Technologies Research Unit (FibEnTech-UBI), Universidade da Beira Interior, Rua Marqu\u00eas D\u2019\u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6165-8899","authenticated-orcid":false,"given":"Andr\u00e9 Costa","family":"Vieira","sequence":"additional","affiliation":[{"name":"Center for Mechanical and Aerospace Science and Technologies (C-MAST-UBI), Universidade da Beira Interior, Rua Marqu\u00eas D\u2019\u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6098-9581","authenticated-orcid":false,"given":"Joana Costa","family":"Vieira","sequence":"additional","affiliation":[{"name":"Fiber Materials and Environmental Technologies Research Unit (FibEnTech-UBI), Universidade da Beira Interior, Rua Marqu\u00eas D\u2019\u00c1vila e Bolama, 6201-001 Covilh\u00e3, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kamarudin, S.H., Mohd Basri, M.S., Rayung, M., Abu, F., Ahmad, S., Norizan, M.N., Osman, S., Sarifuddin, N., Desa, M.S.Z.M., and Abdullah, U.H. 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