Microhardness and thermal study of the annealing effects in vinyl alcohol—ethylene copolymers

Bento

Microporous and Mesoporous Materials

et al. 2016

Hybrid materials based on polyethylene and MCM-41 microparticles functionalized with silanes: Catalytic aspects of in situ polymerization, crystalline features and mechanical properties, Microporous and Mesoporous Materials (2016), doi: 10.1016/j.micromeso.2016 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Mechanical response is observed to be dependent on the content in mesoporous MCM-41 and on the crystalline features of polyethylene. Accordingly, stiffness increases and deformability decreases in the nanocomposites as much as MCM-41 content is enlarged and polyethylene amount within channels is raised. Ultimate mechanical performance improves with MCM-41 incorporation without varying the final processing temperature.

show abstract

Section: A C C E P T E D Accepted Manuscriptmentioning

confidence: 93%

Hybrid materials based on polyethylene and MCM-41 microparticles functionalized with silanes: Catalytic aspects of in situ polymerization, crystalline features and mechanical properties

Bento

Microporous and Mesoporous Materials

et al. 2016

show abstract

“…Table II displays that the melting temperature is independent upon thermal treatment, as occurred in the totally hydrolyzed sample of this series (VAEAc1) and in some other vinyl alcohol-ethylene copolymers totally hydrolyzed. 2,5 In addition, it is seen in Table II that there is an increase in the melting enthalpy value as hydrolysis degree is raised, as mentioned above. It is due to the better-formed crystals, as a less content of acetate groups is present in the copolymer (see Fig.…”

Section: Structure and Thermal Propertiesmentioning

confidence: 54%

“…Therefore, slowly cooled copolymers presented a higher crystallinity and crystallites are larger and more perfect than those in quenched specimens. 2,5,6 Figure 4 shows the DSC traces for the two thermal treatments, Q and S, in the three VAEAc copolymers. It is observed, in the two thermal histories, that the melting peak is shifted to a lower temperature as the residual acetate group content increases, slightly in VAEAc2 and more significantly in VAEAc3.…”

Section: Structure and Thermal Propertiesmentioning

confidence: 99%

The effect of residual acetate groups on the structure and properties of vinyl alcohol-ethylene copolymers

Benavente

J. Polym. Sci. B Polym. Phys.

et al. 2000

“…This feature has been already pointed out in a comprehensive study performed at different T a . 5 The mentioned peak is due to the existence of material whose melting temperature is well below the main endotherm. Such a peak is more significant in quenched than in those slowly cooled specimens because of the original smaller and less perfect crystallites in Q samples.…”

Section: Structure and Thermal Propertiesmentioning

confidence: 99%

“…Such a peak is more significant in quenched than in those slowly cooled specimens because of the original smaller and less perfect crystallites in Q samples. 5,6 Annealing seems to cause an improvement in the crystalline regions of quenched annealed specimens greater than that of the slowly cooled annealed samples. This result could be understood by taking into account the annealing procedure.…”

Section: Structure and Thermal Propertiesmentioning

confidence: 99%

The effect of annealing on the structure and relaxation processes of vinyl alcohol-ethylene copolymers

Benavente

J. Polym. Sci. B Polym. Phys.

et al. 2000