Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-21T21:14:12Z No. of bitstreams: 1 JucikleciaDaSilvaReinaldo_TESE.pdf: 5032340 bytes, checksum: b1beaa4ac0c047c8890f7084d295b5df (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-22T21:03:15Z (GMT) No. of bitstreams: 1 JucikleciaDaSilvaReinaldo_TESE.pdf: 5032340 bytes, checksum: b1beaa4ac0c047c8890f7084d295b5df (MD5) / Made available in DSpace on 2018-02-22T21:03:15Z (GMT). No. of bitstreams: 1 JucikleciaDaSilvaReinaldo_TESE.pdf: 5032340 bytes, checksum: b1beaa4ac0c047c8890f7084d295b5df (MD5) Previous issue date: 2017-11-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho foi realizado um estudo para investigar a influ?ncia da estrutura qu?mica no comportamento reol?gico na regi?o da viscoelasticidade linear das blendas polim?ricas constitu?das de pol?meros acr?licos (poli(metacrilato de metila) homopol?mero (PMMAh), poli(metacrilato de metila) com elast?mero (PMMAe)) e estir?nicos (poliestireno (PS), copol?mero estireno-acrilonitrila (SAN), copol?mero acrilonitrila-butadieno-estireno (ABS) e copol?mero metacrilato de metila-butadieno-estireno (MBS)). A espectroscopia de infravermelho por transformada de Fourier (FTIR) mostrou diferentes bandas caracter?sticas das estruturas qu?mica e a calorimetria explorat?ria diferencial (DSC) identificou as temperaturas de transi??o v?trea (Tg) relacionadas aos acr?licos, estir?nicos e fase elastom?rica do PMMAe, ABS e MBS. Os resultados da composi??o qu?mica do SAN e ABS mostraram que a porcentagem de AN encontravam-se dentro da janela de miscibilidade para as misturas com o PMMA, isto ?, de 25 e 21%, respectivamente. Os resultados reol?gicos a baixas frequ?ncias na regi?o de viscoelasticidade linear mostraram que houve uma mudan?a significativa no comportamento reol?gico em rela??o ao uso do PMMAh, quando comparado ao uso do PMMAe e, mostraram tamb?m, a miscibilidade e imiscibilidade das blendas polim?ricas com varia??o estrutural dos componentes minorit?rios. A microscopia eletr?nica de varredura (MEV) e microscopia eletr?nica de transmiss?o (MET) mostraram a imiscibilidade nas blendas polim?ricas com PS e miscibilidade da blenda PMMAh/SAN, e tamb?m a miscibilidade entre o PMMAh com SAN livre do ABS na blenda PMMAh/ABS, corroborando com os resultados reol?gicos. Entretanto, as blendas polim?ricas com PMMAe apresentaram resultados microrreol?gicos complexos, devido a presen?a da fase elastom?rica. As fotomicrografias mostraram a miscibilidade entre o PMMA e o SAN nas blendas PMMAe/SAN e PMMAe/ABS, onde o PMMAe apresentou part?culas do tipo casca-n?cleo (core-shell) e o ABS apresentou dom?nios de fase dispersa de polibutadieno. / The aim of this work was to investigate the influence of the effect of the chemical structure on the rheological behavior in the linear viscoelastic region of polymer blends consisting of acrylic polymers (poly (methyl methacrylate) homopolymer (PMMAh), poly (methyl methacrylate) with elastomeric particles (PMMAe)) and styrenic polymers (polystyrene (PS), styrene-acrylonitrile copolymer (SAN), acrylonitrile-butadiene-styrene copolymer (ABS) and methyl methacrylate-butadiene-styrene copolymer (MBS)). Fourier transform infrared spectroscopy (FTIR) showed a different bands characteristic of the chemical structures and tje differential scanning calorimetry (DSC) identified the glass transition temperatures (Tg) related to acrylics, styrenics and elastomeric phases of PMMAe, ABS and MBS. The results of the chemical compositions of the SAN and ABS showed that the percentage of AN were within the miscibility window for mixtures with PMMA, ie 25 and 21 wt%, respectively. The rheological results obtained at low frequency in the region of linear viscoelasticity showed that there was a significant change in the rheological behavior in relation to the use of PMMAh when compared to the use of PMMAe and also showed the miscibility and immiscibility of the polymer blends with structural variation of the minority components. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the immiscibility in polymer blends with PS and miscibility in PMMAh/SAN blend, as well as the miscibility between PMMAh and free SAN of the ABS in the PMMAh/ABS blend, corroborating with the rheological results. However, the polymer blends with PMMAe presented complex microrreological results due to the presence of the elastomeric phase. Photomicrographs showed the miscibility between PMMA and SAN in the PMMAe/SAN and PMMAe/ABS blends, where PMMAe presented core-shell particles and ABS showed dispersed phase domains of the polybutadiene.