Abstract
Polymers are frequently used in fields as diverse as aerospace, biomedicine, automotive and in-dustrial vibration damping, where they are often subjected to high strain rate or impact loading. Poly(vinyl chloride) (PVC), and its plasticised variants (PPVC), are just two examples of this broad category of materi-als. Since many polymers exhibit strong rate and temperature dependence, including a low temperature brittle transition, it is extremely important to understand their mechanical responses over a wide range of loading con-ditions.PVC with 60 wt% plasticiser is used in this study, as its highly rubbery nature lends itself well to being used in various load mitigation and energy absorption applications. It is challenging to obtain high strain rate data on rubbery materials using conventional techniques such as the split-Hopkinson (Kolsky) bar. Therefore, alternative approaches are required. Based on previous work developing a framework to predict high rate re-sponseusing a fractional derivative model, Dynamic Mechanical Analysis (DMA) experiments are conducted on the PPVC to construct a master curve of storage modulus. These data are used to part-calibrate a modified Mulliken-Boyce model which also takes into account specimen heating to derive stress-strain relationships at strain rates varying from 0.001 s_1 to 13 500 s_1. This model is further calibrated against experiments conducted in a previous study and shown to provide an excellent description of the behaviour at these rates.
Highlights
Poly(vinyl chloride) (PVC) is an example of a widely used amorphous polymer
To enhance its ductility and energy absorption, a plasticiser based on a phthalate ester compound, such as diisononyl phthalate (DINP) is added to the PVC [1]
This plasticised PVC (PPVC) exhibits strong rate and temperature dependence in its mechanical properties, including the modulus, yield strength and post-yield behaviour. This sensitivity increases with rate due to inhibitions of the secondary (β) transitions [2, 3]; characterising the mechanical properties at high strain rates becomes very challenging
Summary
To enhance its ductility and energy absorption, a plasticiser based on a phthalate ester compound, such as diisononyl phthalate (DINP) is added to the PVC [1] This plasticised PVC (PPVC) exhibits strong rate and temperature dependence in its mechanical properties, including the modulus, yield strength and post-yield behaviour. The low specimen stiffness and wavespeed means that it takes significant time to achieve the static equilibrium prerequisite for analysis, whilst low strengths lead to poor signal to noise ratio [4, 5] For this reason, a modelling framework has been developed, building on previous research [6, 7], to predict the high rate mechanical response of the PPVC via constitutive models calibrated with data obtained accurately at low strain rates and amplitudes [8]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.