1. A process of upcycling post-consumer recycled polypropylene (PCR PP), the
process comprising: melt mixing a blend comprising 50 to 90% (w/w) of a
post-consumer recycled polypropylene (PCR PP) optionally functionalised
5 with maleic anhydride, 0.1 to 2% (w/w) of a catalyst, 5 to 30% (w/w) of an
imine functionalised oil, 0.1 to 1% (w/w) of an antioxidant and optionally a
grafted polypropylene to obtain a vitrimer of post-consumer recycled
polypropylene (PCR PP),
wherein the blend comprises at least one of the grafted polypropylene or the
10 post-consumer recycled polypropylene (PCR PP) functionalised with maleic
anhydride.
2. The process as claimed in claim 1, wherein the grafted polypropylene is
maleic anhydride grafted polypropylene.
3. The process as claimed in claim 1, wherein the grafted polypropylene is in a
15 weight range of 3 to 15%, with respect to total weight of the blend.
4. The process as claimed in claim 1, wherein the catalyst is selected from zinc
acetate, triazabicyclodecene (TBD), triphenylphosphine (PPh3), or zinc (II)
acetylacetonate hydrate.
5. The process as claimed in claim 1, wherein the blend comprises an
20 antioxidant selected from pentaerythritol tetrakis [3- [3,5-di-tert-butyl-4-
hydroxyphenyl]propionate], octadecyl 3-(3,5-di-tert-butyl-4-
hydroxyphenyl)propionate, 3,3',3',5,5',5'-hexa-tert-butyl-a,a',a'-(mesitylene2,4,6-triyl) tri-p-cresol or combinations thereof.
6. The process as claimed in claim 1, wherein the imine functionalised oil is
25 prepared by sequential treatment of an oil to maleation, amination, and with
an aldehyde.
7. The process as claimed in claim 1, wherein the imine functionalised oil has
a degree of functionalisation in a range of 0.3 to 1%, with respect to the total
weight of the blend.
30 8. The process as claimed in claim 1, wherein melt mixing is carried out at a
temperature ranging from 160 to 250 ℃.
24
9. The process as claimed in claim 1, wherein the vitrimer comprises a dynamic
covalent network formed through a reaction selected from imine exchange
reaction, transesterification, or combinations thereof.
10. The process as claimed in claim 1, wherein the vitrimer exhibits yield
5 strength in a range of 23 to 27 MPa.