Preparation and evaluation of mechanical properties of filled PVC/ PVB blends/clay and calcium carbonate

The comparison of mechanical properties of blends of plasticized poly(vinyl chloride) (PVC) with poly(vinyl butyral) (PVB) was the main aim of this study. The possibility of the re-use of recycled PVB from waste of windshields... [ view full abstract ]

The comparison of mechanical properties of blends of plasticized poly(vinyl chloride) (PVC) with poly(vinyl butyral) (PVB) was the main aim of this study. The possibility of the re-use of recycled PVB from waste of windshields was studied. Composites of PVC/PVB blends, montmorillonite (MMT) and CaCO3, prepared by melting and mixing in a twin-screw extruder were evaluated.
PVC plasticized with 38 % of diisononyl phthalate (DINP), and PVB plasticized with 28 % of triethylene glycol, bis(2-ethylhexanoate) (3GO) and recycled PVB (rec. PVB) were tested. The filler as an organically modified MMT with tradenames Cloisite 93A and 30B and CaCO3 were used. The concentration of all the above-mentioned fillers added to the polymeric matrix was 3, 5, 7 and 9 wt. %. Blends used for the determination of mechanical properties of PVB/PVC mixtures in various ratio were prepared in continual BUSS extruder with two kneading chambers. Process conditions were 160 °C of temperature and rotation speed 55 rpm.
The high PVB molecular weight can provide very high tensile strength of material. Measurement showed that fillers do not deteriorate mechanical properties of filled PVC/recycled PVB blends. The same fact was also observed for fillers in virgin PVB. As was shown by TEM analyses - the nanofiller achieves a determinate degree of intercalation, but no full exfoliation (e.g. Image 1).
The improvement of mechanical properties in scale from 60% of PVB was probably caused by mentioned high molecular weight of PVB. Further, the comparison showed that the ideal filling is 3 and 5 wt.% of nanofillers. This study seems to clarify a little more efficiency of PVC/PVB composites applications such as flooring, many uses in civil engineering.
This work was supported by projects TH 01030054 (TACR–Epsilon) and IGA/FT/2016/009.