 | |
ΣΥΜΠΟΛΥΜΕΡΗ ΔΥΟ ΚΑΙ ΤΡΙΩΝ ΣΥΣΤΑΔΩΝ ΣΤΥΡΕΝΙΟΥ-ΙΣΟΠΡΕΝΙΟΥ ΜΕ ΜΙΑ ΔΙΠΟΛΙΚΗ ΟΜΑΔΑ ΣΟΥΛΦΟΒΕΤΑΙΝΗΣ ΣΕ ΕΝΑ Η ΚΑΙ ΣΤΑ ΔΥΟ ΑΚΡΑ ΤΗΣ ΠΟΛΥΜΕΡΙΚΗΣ ΑΛΥΣΙΔΑΣ ΠΑΡΑΣΚΕΥΑΣΤΗΚΑΝ ΜΕ ΤΗΝ ΤΕΧΝΙΚΗ ΤΟΥ ΑΝΙΟΝΤΙΚΟΥ ΠΟΛΥΜΕΡΙΣΜΟΥ. ΣΑΝ ΑΠΑΡΧΗ ΤΗΣ ΧΡΗΣΙΜΟΠΟΙΗΘΗΚΕ ΤΟ 3-ΔΙΜΕΘΥΛΟΑΜΙΝΟΠΡΟΠΥΛΟΛΙΘΙΟ. Η ΑΚΡΑΙΑ ΤΡΙΤΑΓΗΣ ΑΜΙΝΟΜΑΔΑ ΜΕΤΑΤΡΑΠΗΚΕ ΣΕ ΟΜΑΔΑ ΣΟΥΛΦΟΠΡΟΠΥΛΟΒΕΤΑΙΝΗΣ ΜΕ ΑΝΤΙΔΡΑΣΗ ΜΕ ΚΥΚΛΟΠΡΟΠΑΝΟΣΟΥΛΤΟΝΗ. ΟΙ ΙΔΙΟΤΗΤΕΣ ΤΩΝ ΠΟΛΥΜΕΡΩΝ ΑΥΤΩΝ ΣΕ ΑΡΑΙΑ ΔΙΑΛΥΜΑΤΑ (Σiv>
THE DILUTE SOLUTION PROPERTIES OF DIBLOCK AND TRIBLOCK COPOLYMERS OF STYRENE AND ISOPRENE WITH ONE DIPOLAR SULFOBETAINE GROUP AT EITHER OR BOTH ENDS OF THE CHAIN WERE EXAMINED IN CARBON TETRACHLORIDE BY STATIC AND DYNAMIC LIGHT SCATTERING, AS WELL AS BY VISCOMETRY. THE COPOLYMERS WERE PREPARED BY ANIONIC POLYMERIZATION TECHNIQUES USING [3-(DIMETHYL AMINO)PROPYL] LITHIUM AS INITIATOR. THETERTIARY AMINE AND GROUPS WERE CONVERTED TO SULFOBETAINES BY RECUTION WITH CYCLOPROPANE SULTONE. AGGREGATION NUMBERS DERIVED FROM STATIC AND DYNAMIC METHODS ARE IN GOOD AGREEMENT AND DECREASE WITH INCREASING MOLECULAR WEIGHT OF THE POLYMERIC TAIL. ALTHOUGH AGGREGATION IS REDUCED WHEN SMALL AMOUNTS OF 2-METHYLCYCLOHEXANOL ARE ADDED, IN CCL4 SOLUTIONS, IT PERSISTS EVEN AT CONCENTRATIONS OF ALCOHOL AS HIGH AS 5% (V/V). GELS, FORMED BY THE DISFUNCTIONAL SPECIES, AREALSO DESTROYED BY ADDITION OF ALCOHOL. THE HYDRODYNAMIC BEHAVIOUR OF THE AGGREGATES FORMED BY THE MONOFUNCTIONAL SPECIES, RESEMBLES ...
THE DILUTE SOLUTION PROPERTIES OF DIBLOCK AND TRIBLOCK COPOLYMERS OF STYRENE AND ISOPRENE WITH ONE DIPOLAR SULFOBETAINE GROUP AT EITHER OR BOTH ENDS OF THE CHAIN WERE EXAMINED IN CARBON TETRACHLORIDE BY STATIC AND DYNAMIC LIGHT SCATTERING, AS WELL AS BY VISCOMETRY. THE COPOLYMERS WERE PREPARED BY ANIONIC POLYMERIZATION TECHNIQUES USING [3-(DIMETHYL AMINO)PROPYL] LITHIUM AS INITIATOR. THETERTIARY AMINE AND GROUPS WERE CONVERTED TO SULFOBETAINES BY RECUTION WITH CYCLOPROPANE SULTONE. AGGREGATION NUMBERS DERIVED FROM STATIC AND DYNAMIC METHODS ARE IN GOOD AGREEMENT AND DECREASE WITH INCREASING MOLECULAR WEIGHT OF THE POLYMERIC TAIL. ALTHOUGH AGGREGATION IS REDUCED WHEN SMALL AMOUNTS OF 2-METHYLCYCLOHEXANOL ARE ADDED, IN CCL4 SOLUTIONS, IT PERSISTS EVEN AT CONCENTRATIONS OF ALCOHOL AS HIGH AS 5% (V/V). GELS, FORMED BY THE DISFUNCTIONAL SPECIES, AREALSO DESTROYED BY ADDITION OF ALCOHOL. THE HYDRODYNAMIC BEHAVIOUR OF THE AGGREGATES FORMED BY THE MONOFUNCTIONAL SPECIES, RESEMBLES THAT OF STAR POLYMERS IN GENERAL.
περισσότερα