Abstract
The complex and incompletely understood phenomenon of shear-induced crystallization of polymers may be nowadays analysed via the in situ POM-shear stage methodology. In this research, the two main issues were investigated with the use of the Linkam CCS450 shear stage connected with POM microscope. It was found that the secondary nucleation in the tree well-known temperature regimes plays the greater role in the overall crystallization kinetics than the shear induced primary nucleation. Furthermore, it was found that the tendency towards β-phase formation in shear conditions is dependent on the temperature value during shear treatment. It may be concluded that the temperature is the key parameter in the primary and secondary nucleation process and beta-phase formation in the iPP melts.
Highlights
Since its discovery, the isotactic polypropylene has been found to have many applications in various areas in view of its satisfactory properties and relative low material cost [1,2,3]
The secondary nucleation process may occur in three different crystallization regimes: regime I – where the g > > i; regime II – where g ~ i and regime III – where g < < i (Fig. 1) [19, 20]
The research was divided into three main parts: I) observations of crystallization kinetics, II) the temperature dependence of shear nucleating ability and III) the formation of β phase of isotactic polypropylene (iPP)
Summary
The isotactic polypropylene (iPP) has been found to have many applications in various areas in view of its satisfactory properties and relative low material cost [1,2,3]. Keywords Isotactic polypropylene · Shear-induced crystallization · Supermolecular structure · Spherulites formation The β form of isotactic polypropylene can be obtained by providing suitable conditions for crystallization, such as high temperature gradients, the presence of shear forces or by using appropriate nucleating agents.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
