Toward Mechanical Recycling of Polystyrene/Polypropylene Blends with Bottlebrush-Modified Graphene Oxide as a Compatibilizer

Abstract

The compatibilization of immiscible polystyrene/polypropylene (PS/PP) blends with virgin graphene oxide (GO-V) and GO modified with a bottlebrush reactive copolymer layer (GO-P) is reported. This practically important blend was chosen since, currently, PS and PP are recycled to a very low degree. The amphiphilic bottlebrush copolymer synthesized by us contained hydrophobic and hydrophilic side chains and was attached to the GO nanosheets via epoxy functionality. The GO modification and the introduction of GO into the blend were conducted from water. Thus, the introduction of the compatibilizing nanomaterial can be conducted during the mechanical recycling washing stage in a real-world situation. The final blend was prepared via melt mixing using an extruder. We examined the influence of GO modification and the mixing order on the blends' morphology, rheology, and mechanical properties. Thermodynamic calculations predicted a higher interfacial activity of GO nanosheets in PS/PP/ GO-P blends than that in PS/PP/GO-V blends. The morphological and rheological study assessed this prediction. It was demonstrated that the bottlebrush-modified GO-P sheets were readily driven to the PS/PP interphase. The mechanical measurements showed enhanced mechanical properties for PS/PP/GO-P blends, especially for those in which GO was first premixed with PS.

Janus bottlebrush compatibilizers

“…However, it is demanding to perform an in-depth investigation on the interfacial conformation for understanding the behind compatibilization mechanism. [22][23][24][25][26] In this study, bottlebrush random copolymers (BRCPs), where two homopolymer chains are randomly attached to a backbone chain, are shown to adopt a Janus-type configuration at a homopolymer interface, placing the different chains in the different phases. 27 This reconfiguration effectively reduces steric crowding at interface, with less cost of configurational entropic penalty compared to bottlebrush BCPs.…”

Plasticization of Polystyrene with Copolymers Based on High Oleic Soybean Acrylic Monomer

“…■ EXPERIMENTAL SECTION Materials. High oleic soybean oil (Perdue Agribusiness LLC), myrcene (Sigma-Aldrich), styrene (Sigma Alrich), sodium dodecyl sulfate (SDS, VWR), sodium chloride (VWR), N-(hydroxyethyl) acrylamide (TCI America), sodium hydroxide (Alfa Aesar), magnesium sulfate (Sigma-Aldrich), polystyrene (PS, Sigma-Aldrich) with MFI = 2 g/10 min (230 °C, 2.16 kg), 31 methanol (Sigma-Aldrich), chloroform (Sigma-Aldrich), and hexane (Sigma-Aldrich) were used as received. 2,2′-Azobis(2-methylpropionitrile) (AIBN; Sigma-Aldrich) was purified with recrystallization from methanol.…”

Mechanism of Low‐Temperature Brittle–Ductile Transition of Polypropylene/Low‐Density Polyethylene Blend Foam under Compressive Stress Caused by Cell Stretching

“…Polypropylene (PP), as a well-known versatile commodity plastic with outstanding comprehensive properties, such as excellent chemical corrosion resistance, easy processability, and low cost, has been widely applied as films, sheets, pipes, and various injection molded products ranging in the field of packaging, household appliance, and construction industries, etc. [1][2][3][4][5][6][7] However, due to the relatively poor flexibility of the molecular chain, PP shows the poor low-temperature toughness, which greatly restricts the wide applications of PP in frigid regions. [8,9] The long-term servicing stability of polymer materials is closely related to its applied temperature, and the research on low-temperature brittle-ductile transition of polymer materials is essential to determine the low-temperature service conditions, which is beneficial for maximizing the service performance and prolonging the service life of the materials.…”

“…Polypropylene (PP), as a well‐known versatile commodity plastic with outstanding comprehensive properties, such as excellent chemical corrosion resistance, easy processability, and low cost, has been widely applied as films, sheets, pipes, and various injection molded products ranging in the field of packaging, household appliance, and construction industries, etc. [ 1–7 ] However, due to the relatively poor flexibility of the molecular chain, PP shows the poor low‐temperature toughness, which greatly restricts the wide applications of PP in frigid regions. [ 8,9 ]…”