| Titre : | Periodic switching of monomer additions for controlling the compositions and microstructures of segmented and random ethylene-propylene copolymers in polypropylene in-reactor alloys (2011) |
| Auteurs : | Zhou Tian, Auteur ; Xue-Ping Gu, Auteur ; Gang-Liang Wu, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Industrial & engineering chemistry research (Vol. 50 N° 10, Mai 2011) |
| Article en page(s) : | pp. 5992-5999 |
| Note générale : | Chimie industrielle |
| Langues : | Anglais |
| Tags : | Reactor Microstructure |
| Résumé : | This work aims at shading fundamental insights into mechanisms that dictate the composition and microstructure of polypropylene/poly(ethylene-co-propylene) (PP/EPR) in-reactor alloys produced by the multizone circulating reactor (MZCR) technology, a novel one for polyolefin production. For this purpose, this technology is simulated by a batch process with periodic switching of monomer additions. An increase in the switch frequency leads to a decrease in the fraction of ethylene/propylene random (amorphous) copolymers denoted as EPR and an increase in the fraction and the length of PP segments of ethylene/ propylene segmented (partially crystalline) copolymers denoted as EPS. Concomitantly, the size of the dispersed phase domains (EPR) decreases, and its size distribution becomes more uniform as a result of the decrease in the fraction of the EPR and the increase in that of the EPS which acts as a compatibilizer for PP/EPR in-reactor blends. Mechanical properties of the PP/EPR in-reactor blends are also discussed. |
| DEWEY : | 660 |
| ISSN : | 0888-5885 |
| En ligne : | http://cat.inist.fr/?aModele=afficheN&cpsidt=24158896 |
