Polymer synthesis from 3-methylbutene-1

Grant, Michelle (1993)

Thesis (M.Sc.) -- University of Stellenbosch, 1993.

Thesis

ENGLISH ABSTRACT: Two homopolymers of 3-methylbutene-1 were synthesized with different cocatalyst/catalyst ratios of the Zlegler-Natta catalyst system. The 3-methylbutene-1 homopolymers were characterized as fully as pusslble. The stereoregularity of poly(3-mathylbutene-1) was determined with three different methods. The thermal and thermo-oxidative stabilities of poly(3- methylb~tene-1) were determined by differential scanning calorimetry. A method of stabilizing poly(3-methylbutene-1) with the assistance of an antistatic agent was studied. Two vlnyltrlmethylsllane homopolymers were synthesized with a Zlegler-Natta catalyst system and characterized. A series of 3-methylbutene-1-vinyltrimethylsilane copolymers were synthesized. A correlation was attempted between the amount of vinyltrimethylsilane comonomer Incorporated into the copolymer and the properties of the copolymers. All the synthesized copolymers were characterized as fully as possible. The silicon content of the copolymers were determined by elemental analysis and the protonInduced gamma emission technique to givE' the amount of vinyltrimethylsilane uomonomer incorporated Into the various copolymers. The monomor reactivity ratios of the copolymers were calculated by the Fineman-Ross method and refined with the Tidwell-Mortimer method. It was shown that poly(3-methylbutene-1) was a high-melting, highly lsotactic, and highly insoluble polymer. Poly(3-methylbutene-1) had a high thermal stability In the absence of air, but a low therrnooxldative stability in the pre.~ence of air. Poly(3-methylbutene-1) could be stabilized with the aid of an antistatic agent, Dehydat 51 Special, and this method also proved to be a way of solubilizing poly(3-methylbutene-1 ). Poly(vinyltrimethylsilane) Is a very high-melting polymer. The melting point of poly(3-methylbutene-1j decreased by copolymerization of the compound with vinyltrimethylsilane, but the decrease was no\ as great as was expected. The isotactlclty of poly(3-methylbutene-1) was also lowered through copolymerlzatlon with vlnyltrimethylsilane. The measuring of the amount of silicon present ir: the various copolymers with elemental analysis techniques Indicated that a small percentage of vinyltrimethylsilane was actually Incorporated into the copolymers, although large amounts of it were added to the comonomer feed. The calculation of the monomer reactivity ratios of the copolymers showed that vinyltrimethylsilane had a very low reactivity ratio, namely, o, compared with that of 3- rnethylbutene-1, which was on average 19,6.

AFRIKAANSE OPSOMMING: Twee homopolimere van 3-metlelbuteen-1 Is geslntetiseer met versklllende ko-katalls/katalls verhoudinge van die Ziegler-Natta katalls slsteem. Die 3-metlelbuteen-1 homopollmere Is so volledlg moontlik gekarakteriseer. Die stereoregulariteit van pol1(3-metielbuteen-1) is met drle versklllende metodes bepaal. Die termlese en 'ermo-oksidatiewe stablliteit van pol1(3-melielbuteen-1) Is bepaal met differensiele skandeer kalorimetrie. 'n Metode om poli(3-metielbuteen-1) le stabiliseer met die hulp van 'n antistatiese middel Is bestudeer. Twee vinleltrlmetlelsllaan homopollmere Is gesintetlseer met 'n Zlegler-Natta katalls slsteem en gekarakterlseer. 'n Reeks 3-metlelbuteen-1-vinieltrimetlelsllaan kopollmere is gesintetiseer. 'n Paging Is aangewend om 'n korrelasie tussen die hceveelheid vinieltrimetielsilaan komonomeer en die elenskappe van die kopollmere le verkry. Al die gesintetiseerde kopollmere is so volledig as moontlik gekarakterlseer. Die silikon inhoud van die kopollmere is bepaal met 'n element analise metode en die proton-geTnduseerde gamma emissie tegniek om die hoeveelheid vinieltrimetielsilaan komonomeer geTnkorporeer In die verskillende kopollmere te gee. Die monomeer reaktiwiteitsverhoudinge van die kopollmere is bepaal met die Fineman-Ross metode en verfyn met die Tidwell-Mortimer metode. Daar is getoon dat poli(3-metlelbuteen-1) 'n hoe smelt punt, hoe isotaktlsiteit, en hoe onoplosbaarheld besit. Po11(3-mellelbuteen-1) besit 'n hoe termlese stablllteit In die afweslgheld van ILI(;, maar 'n lae termo-oksldatiewe stabiliteit in die teenwoordlgheld van lug. Pol1(3-metlelbuteen-1) kan gestabiliseer word met die hulp van 'n antistatiese ~"'1del, Dehydat 51 Special, en hlerdle metode Is ook bewys as 'n manler om pol1(3-metielbuteen-1) op le las. Poli(vinieitrimetielsilaan) is 'n polimeer met 'n bale hoe smeltpunt. Die smeltpunt van pol1(3-metielbuteen-1) Is verlaag deur kopolimerisasle met vlnieltrimetielsilaan, maar nle soveel as wat verwag is nie. Die isotaklisiteit van poli(3-metlelbuteen-1) Is ook verlaag deur kopolimerisasie met vinle11rimetielsilaan. Die hoeveelheid sillkon teenwoordig in die verskillende kopolimere he! getoon dat slegs 'n klein persentasie van die vinieltrirnetielsilaan In die ~opollmere ge"inkorporeer is, alhoewel groat hoeveelhede daarvan by die komonomeer voer gevoeg is. Die berekening van die monomeer reaktiwiteitsverhoudlnge van die kopolimere het getoon dat vinieltrimetielsilaan 'n baie lae reaktlwiteitsverhouding besit, o, In vergelyklng met die reaktiwiteitsverhouding van 3-rnetielbuteen-1, wat gemiddeld 19,6 is.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/58111
This item appears in the following collections: