AMORPHOUS POLYOLEFINS

Abstract: Amorphous polyolefins include units from acyclic mono-olefins, particularly ethylene, and units derived norbornene type olefins including units of formula (I), where: n1 is 0, 1 or 2, n2 is 0 or 1 and n1 + n2 > 0; n3 is 0 or from 1 to 4; n4 is 0 or from 1 to 4; R<1>, R<2> and R<3> are each hydrogen, halogen, alkyl, cycloalkyl, aralkyl, alkaryl or aryl; the ring group A<1> is 1,2-cyclohexylene or a 1,2-phenylene which may be unsubstituted or substituted with halogen, alkyl or aryl and may have further 1,2-cyclohexylene or 1,2-phenylene fused to it. The polymers can be made by polymerisation of the monomers under Ziegler-Natta catalysis. They are amorphous and transparent having high Tg's and are useful in optical components such as optical discs.

Description: A nw nπs Pnτ_vm.ιπmκ_ This invention relates to amorphous polyolefins and in particular to amorphous copolymers of low molecular weight acyclic, particularly alpha- c- aliphatic olefins such as ethylene and/or propylene with bridged ring olefinic monomers especially norbornene derivatives. Polyethylene and (isotactic) polypropylene are crystalline polymers having good chemical, particularly solvent, resistance and are substantially unaffected by moisture. They have relatively low glass 1 Q transition temperatures (Tg) and thus have low strength at elevated temperatures. Being crystalline, they are translucent rather than optically clear in the wavelength range of visible light. Their low strength and relatively poor optical properties mean that these polymers are not suitable for applications such as optical disks, optical fibres **5 and other similar optical components. It has long been known that higher Tg amorphous polymers can be made by copolymerising ethylene with norbornene and certain derivatives, for example as described in British Patent Specification Nos. 777414, 951022, US Patent Specifications Nos. 2799668 and 2883372, West German Offenlegungsschrift No 2421838 and East 20 German Patent Specifications Nos. 215087, 222317 and 246903. More recently a number of specifications in the name of Mitsui Petrochemical Industries have been published, including European Published patent applications Nos. 0156464 A (US equivalent No 4614778), 0203799 A, 0291208 A, and 0310394 A, which develop the idea of making 5 amorphous polyolefins copolymers based on ethylene or a similar aliphatic monomer and derivatives of norbornene such as 6-methyl-l,4,5,8-dimethano- l,4,4a,5,6,7,8,8a-octahydronaphthalene (MDMON) . The present invention is based on the finding that certain cyclic aromatic substituted derivatives of bridged cyclic olefinic monomers can 3 give clear amorphous copolymers with acyclic olefins having a good combination of optical, mechanical and physico-chemical properties. This combination of properties makes these copolymers candidates for use in optical products such as optical discs, especially CD-ROM, WORM and erasable or re-writable optical discs, optical fibres and related devices and components. Accordingly, the present invention provides an amorphous polymer containing units derived from an acyclic mono-olefin and units derived SUBSTITUTE SHEET from a norbornene type olefin including units of the formula (I): where: ni is 0, 1 or 2, n2 is 0 or 1 and n-j. + n£ > 0; is 0 or from 1 to 4; each R 1 , each R 2 and each R 3 , is independently a hydrogen or halogen atom, or an alkyl, cycloalkyl, aralkyl, alkaryl or aryl group; the ring group A- is 1,2-cyclohexylene or a 1,2-phenylene group which may be unsubstituted or substituted with one or more halogen atoms, alkyl or aryl groups and may have further 1,2-cyclohexylene or a 1,2-phenylene ring group(s) respectively fused to it. The invention includes a method of making an amorphous copolymer as defined above which comprises, polymerising a mixture of at least one acyclic mono-olefin and at least one monomer of the formula (II): where: nτ_, 2, 3, and are each, independently, as defined above for formula (I) ; SUBSTITUTESHEET each R 1 , each R 2 , each R 3 , is, independently, as defined above for formula (I) or is an alkenyl group or an alkynyl group; and ring group A 2 is a 1,2-phenylene ring group which may be unsubstituted or substituted with one or more halogen atoms, alkyl or 5 aryl groups and may have further 1,2-phenylene ring group(s) fused to it; and, if necessary, hydrogenating the polymer. In the formulae (I) and (II) , the groups R 1 , R 2 and R 3 are particularly hydrogen atoms although one or more, but preferably not more 1 - than 3, of them may be substituents as defined above. In the formulae, halogen atoms are preferably chlorine atoms; alkyl groups are particularly C^ to C alkyl, especially methyl or ethyl, groups; cyclo- alkyl groups are particularly cyclohexyl groups; alkenyl groups are particularly C2 to C5 alkenyl, especially ethenyl or propenyl, groups; '5 alkynyl groups are particularly C2 to C5 alkynyl, especially ethynyl or propargyl, groups; aralkyl groups are particularly phenyl substituted 0χ to C4 alkyl groups, especially benzyl or phenylethyl groups; alkaryl groups are particularly Ci to C4 alkyl substituted phenyl groups; and aryl groups are particularly phenyl groups. Alkyl, cycloalkyl, aralkyl, 0 alkaryl or aryl groups or substituents in formulae (I) and (II) can be further substituted with halogen atoms, alkyl, alkenyl, alkynyl, cyclo¬ alkyl, aralkyl, alkaryl or aryl groups, in particular as above specified. The index ni is most desirably 0 or 1, but, as is described below, the synthesis of the corresponding monomers (II) can conveniently be 5 carried out by a Diels-Alder reaction that can lead to a mixture of monomeric species of the formula (II) thus giving an average value of ni which is non-integral. The indices 3 and 114 are most usually equal, and in particular they are both 1 (to give a cyclohexyl ring) or both 2 (to give a cyclooctyl ring). It is also possible for both to be zero to give C a cyclobutyl ring or one to be 0 and the other 1 (to give a cyclopentyl ring) . The values of the indices n-j., and n2 give particular sub-classes of repeating units of the formulae (I) a to c and corresponding monomers (II) a to c: SUBSTITUTESHEET when n__ is 0 and n2 is 1: (Da (H)a in particular, (I)a and (II)a include compounds where the ring A 3 is a cyclobutenylene n3=n =0), cyclopentenylene ( 3=l, 4»0) , cyclohexenylene (particularly a l,2-cyclohex-4-enylene; 3= 4=l), or cyclooctenylnene (particularly a l,2-cyclooct-5-enylene; 3= 4=2), ring, when n__ is 1 or more and 2 is 0: when nτ_ is 1 or more and 2 is 1: (I)c SUBSTITUTE SHEET (II)c As for (I)a and (II)a, (I)c and (II)c include compounds where the ring A 3 is a cyclobutenylene (n3*= 4 β 0) , cyclopentenylene (n3=l, n =0), cyclo¬ hexenylene (particularly a l,2-cyclohex-4-enylene; n3=n4=l), or cyclo¬ octenylnene (particularly a l,2-cyclooct-5-enylene; n3*=n4*=2), ring. " 5 In the formulae (I)a to c and (II)a to c: 3 and n4, as appropriate, each R****, each R 2 and each R 3 and the ring group A**** are, independently, as defined above for formula (I) or formula (II) respectively. (A 3 is a label for the ring rather than defining a separate ring group.) The amorphous copolymer of the invention includes units derived from at least one acyclic mono-olefin especially ethylene, propylene or a mixture of the two. Units derived from other mono-olefins, particularly alpha-olefins, e.g. C4 to C5 alpha-olefins, or vinyl aromatic monomers e.g. styrene or vinyl toluene, can be used although these will not :5 normally be used to the exclusion of ethylene or propylene. Mixtures of acyclic mono-olefins, particularly alpha-olefins, and combinations of acyclic mono-olefins with relatively small proportions of other olefinic monomers can be used. In such mixtures it is desirable that the main part of units derived from the olefin [other than units derived from :- norbornene type monomers, including units of the formula (I)] are ethylene and/or propylene. The presence of significant ethylenic unsaturation in the polymer tends to promote undesirable propensities to cross-linking during forming processes leading to the generation of gels. Thus, in use the copolymers z. of the invention preferably do not have significant ethylenic unsaturation. From the general formula (II) above, it is clear that monomers to make the polymers of the invention can contain additional ethylenic unsaturation i.e. unsaturation not involved in the desired EET copolymerisation reaction, and this unsaturation will give rise to unsaturated polymers. The source of such additional unsaturation in the copolymers can be the monomers of the formula (II) or other unsaturated monomers used in the polymerisation. Ethylenically unsaturated copolymers will, typically according to the invention, be hydrogenated to remove this additional ethylenic unsaturation before forming of the polymers into end products. The extent of hydrogenation can be sufficient to remove the additional ethylenic substitution in the copolymer or it can go further, by hydrogenating the aromatic rings A 2 in 1 - the monomer, see formula (II), to give a substantially saturated polymer. Of course, the hydrogenation of the aromatic rings can be carried out on polymers without additional ethylenic polymerisation. The amorphous copolymer includes units of the formula (I) above and can include units derived from other norbornene type monomers such as Λ > norbornene itself, alkyl substituted norbornenes, such as methyl norbornene (5-methylnorbornene) and MDMON. Units derived from ethylenically unsaturated norbornene type monomers can be used with reduction of the copolymer is reduced to remove the ethylenic unsaturation. Examples of such monomers include dicyclopentadiene and 20 ethylidene norbornene. The proportions of the norbornene type olefin and the acyclic mono- olefin in the amorphous copolymer have a strong influence on the properties of the copolymer. If the units derived from the norbornene type olefin represent less than about 10 mole 2, the polymer product is 2- likely to be crystalline to a significant extent and, in practice, products containing fractions greater than 602 of units derived from the norbornene type olefin are difficult to prepare. The copolymers of this invention will more usually contain from 15 to 40 mole 2 of units derived from the norbornene type olefin(s). Among the units derived from the -- norbornene type olefin, the proportion of units of the formula (I) will usually be at least 252 and more usually at least 502. Generally, within these limits, a higher proportion of units derived from the norbornene type olefin will give a copolymer having a higher Tg and higher rigidity. The proportion of units derived from acyclic mono-olefin monomer(s) Ξ5 in the copolymer will, correspondingly, generally be from 90 to 40 particularly from 85 to 60 mole 2. The bulk of this will most usually be units derived from ethylene. Thus, a typical copolymer will contain rom 85 to 60 mole Z of units derived from ethylene, although up to about 50 mole 2 of these units can be replaced by units derived from propylene. The proportion of units derived from olefinic monomers, other than ethylene and propylene, will be less than the combined proportion of ethylene and propylene and will usually not be greater about than 5 10 mole 2 of the total monomer content of the copolymer. The monomers of the formula (II) above can be made by Diels-Alder type reaction(s) between suitable precursors under typical Diels-Alder conditions. Monomers of the formula (II)a can be made by reacting an anthracene "- (substituted as appropriate for the monomer desired) with a corresponding dieneophile. Where the ring A 3 is a 5- or more membered ring, the dieneophile will typically be the corresponding cyclic diene, particularly cyclopentadiene (behaving as a dienophile despite, itself, being a conjugated diene), 1,4-cyclohexadiene and 1,5-cyclooctadiene, to "5 give the 5-, 6- and 8-membered ring olefin monomers. Where the ring A 3 is a 4-membered ring, the dieneophile will usually be the corresponding 3,4-dihalocyclobutene (particularly a 3,4-dichlorocyclobutene) . The immediate product of this Diels-Alder reaction is a dihalo-monomer, which can be converted into a monomer of the formula (II) by dehalogenating it. 0 Thus reaction of 3,4-dichlorocyclobutene with 9,10-dibromoanthracene followed by reduction with lithium amalgam and decomposition of the product with water gives the monomer of the formula (II)a with __= 2= and both R 3 's being hydrogen atoms and reaction of 3,4-dichlorocyclo- butene with 9,10-dimethylanthracene followed by reduction with zinc gives 5 the monomer of the formula (II)a with and both R 's being methyl groups. Monomers of the formula (II)b where n__ is 1 can be made by reacting an anthracene (substituted as appropriate for the monomer desired) with a corresponding di-olefin bridged ring dieneophile such as a 2 1,4-norbornadiene (substituted as appropriate for the monomer desired). The corresponding monomers where n*-_ is greater than 1 can be made by a further Diels-Alder reaction from monomers where n*]_ is 1 acting as a dienophile with a cyclopentadiene (substituted as appropriate for the monomer desired) as the diene. 5 Monomers of the formula (II)c can be made by reacting a monomer of the formula (II)a acting as a dienophile with a cyclopentadiene (substituted as appropriate for the monomer desired) as the diene. In making monomers where zι__ is greater than 0, a 1:1 molar ratio of SHEET the cyclopentadiene to dienophile precursor [of the formula (II)a, where i is 0, or of the formula (IΙ)bj will give monomers having an approximate value of the index ni of 1. Higher values of this index can be obtained by increasing the molar proportion of the diene. The monomers obtained by the reaction, particularly at such higher proportions of the cyclopentadiene, will typically be a mixture of compounds of differing values of ni and the average value of ni will thus usually be non-integral. The monomers of the formula (II)a, where the ring A 3 is a 5- or 6- " 2 membered ring, can be somewhat less reactive in the copolymerisation reaction than other monomers of the formula (II). We believe that this is because the ring A 3 in the monomer is less strained than in other monomers of the formula (II). Accordingly, we generally prefer to convert such monomers into the corresponding monomers of the "5 formula (II)c for polymerisation. The copolymers of the invention can be synthesised by polymerisation reactions which are generally known. Typically, the polymerisation will be carried out in the presence of a Ziegler-Natta type catalyst system. One restriction on the polymerisation is that it should avoid formation 20 of polymer by the so-called ring opening metathesis polymerisation (ROMP) mechanism, as this makes (co-)polymers which contain ethylenic double bonds. We have successfully used a catalytic system based on a vanadium organic compound, particularly vanadium(III)acetylacetonate [V(acac)3] or dichloroethoxyoxovanadium [V0(0Et)Cl2] , as catalyst, and an aluminium 25 haloalkyl, particularly diethyl aluminium chloride (DEAC), as co-catalyst, in a molar ratio in the range 1:4 to 1:20, usually about 1:10. The amount of the vanadium catalyst used will be chosen for best results, but will typically be from 1/200 to 1/1000 mole of catalyst per mole of the total monomer polymerised. Typical concentrations in the 2 ~ polymerisation reaction mixture are about 0.1 to 5, particularly about 0.5, mmol.l" * -*- for vanadium and labout 1 to 50,particularly about 5, mmol.l" 1 for aluminium. The polymerisation reaction is typically carried out with the monomers in solution e.g. in a hydrocarbon solvent such as toluene. Ξf Conveniently, the acyclic olefin monomer(s) , particularly ethylene and/or propylene, are introduced into the reaction mix by bubbling the gaseous acyclic olefin monomer into the solution. To reduce the chance of forming a homopolymer of the acyclic olefin monomer, which would SUBSTITUTESHEET interfere with the desired reaction e.g. by precipitating out of solution and blocking the gas inlet pipe, it is convenient to dilute the acyclic olefin monomer with an inert carrier gas such as dry nitrogen. The reaction will typically be carried out at or somewhat below ambient temp- 5 erature e.g. in the range about -30 to about 30°C, especially from 0 to 10°C, although higher temperatures can be used to effect faster reaction, and in a water and oxygen free atmosphere. The reaction proceeds suitably fast, for laboratory synthesis, under atmospheric pressure although higher pressures can be used to increase the effective concen- " tration of gaseous monomer(s), particularly ethylene and/or propylene. In the polymerisation and for given reaction conditions, including the concentration of the norbornene type monomer(s), the rate of adding the acyclic olefin monomer(s) will determine the relative proportions of the norbornene type monomer(s) to the acyclic olefin monomer(s). The " 5 desired proportion will, thus, be used to decide the rate of addition of the acyclic olefin monomer(s) and the proportion of diluent gas used. As is common in this type of polymerisation reaction, gaseous hydrogen can be added as a chain transfer agent to control the molecular weight of the polymer produced. The polymerisation reaction can be carried out as a 0 batch or as a continuous process. The copolymers of the invention are amorphous polymers and are optically transparent (rather than translucent). As made the polymers including aromatic rings can be coloured, usually fairly pale yellow. We think it likely that this reflects absorption by the aromatic ring 5 systems in the blue visible or near ultra violet region of the spectrum although it may merely be the result of small quantities of coloured impurities. Fully hydrogenated polymers of the formula (I) are substantially colourless. We believe that, in the polymers of the invention, the respective units derived from different monomers are 2 distributed randomly, both in terms of the chain sequence and the stereochemistry of the sidechains. They typically have Tg values in the range 110 to 220°C, good stiffness properties and are substantially unaffected by water or atmospheric moisture. They can be fabricated into optical components such as optical discs, especially CD-ROM, WORM and ϊ erasable or re-writable optical discs, optical fibres and related devices and components. Accordingly the invention includes an optical component including an amorphous copolymer of or made by the method of the invention. The following Examples illustrate the invention. All parts and percentages are by weight unless otherwise stated. Abbreviations Monomers and reagents for monomers (capital letters are solely to indicate the origin of the abbreviation) : MDMON - 6-Methyl-l,4,5,8-DiMethano-l,4,4a,5,6,7,8,8a-0ctahydro- Naphthalene : 2 DBTCT - 9,10,11,12-DiBenzoTetraCyclo[6.2.2.1 3 » 6 .0 2 ' 7 ]Trideca- 4,9,11-triene MDBTCT - l-Methyl-9,10,11,12-DiBenzoTetraCyclo[6.2.2.1 3 » 6 .0 2 ' 7 ]- Trideca-4,9,11-triene DCDBTCT - l,8-DiChloro-9,10,ll,12-DiBenzoTetraCyclo[6.2.2.1 3 ** 6 .0 2 ' 7 ]- " z Trideca-4,9,ll-triene DBTTT - 10,11,12,13-DiBenzoTricyclo[8.2.2.0 2 » ]Tetradeca- 5,10,12-Triene Other materials: acac - acetylacetonate e.g. vanadium(III)acetylacetonate is 20 abbreviated as V(acac)3 Et - ethyl e.g. dichloroethoxyoxovanadium is abbreviated as V0(0Et)Cl 2 Etv - ethylene Prv - propylene 25 DEAC - diethylaluminium chloride EASC - ethylaluminium sesquichloride V-Cat - vanadium catalyst Al-Cat - aluminium alkyl co-catalyst 21 Test Methods Proportions of respective monomers incorporated into polymers - these are derived by measuring the ratio of aromatic to aliphatic protons from the integration of -E nmr analysis of the copolymer. Spectra were taken on ε 25 GSX 400 MHz spectrometer using 1,1,2,2-deuterated tetrachloroethane as solvent. From knowledge of the structure of the monomers, the molar proportion, of the residues derived from the respective monomers was calculated. The result is expressed as mole 2, usually by quoting the ITUTE SHEET ethylene content (EC) or propylene content (PrC). Glass Transition temperature (Tg) - was measured by Dynamic Mechanical Analysis (DMA) (on the principles described in the Encyclopedia of 5 Polymer Science and Engineering 2nd Edition Volume 5 at pages 299 to 329) using a Du Pont Instruments 981 Dynamic Mechanical Analyser at a heating rate of 10 o C.min _1 . The results are quoted as the peak temperature of the loss modulus E" in °C. "0 Intrinsic Viscosity (IV) - was measured in decalin at 135°C using an Ubblehode suspended level dilution viscometer. The results are quoted in dl.g-i. Water Absorption (WA) - was measured by the method of ASTM D570. The "5 results are quoted in 2 by weight. X-Ray Diffraction (XRD) - wide angle X-ray diffraction was carried out on a Phillips PW1710 Diffractometer, using a 1730 generator with 0.1° step size and a 6 second count at temperatures from 4 to 40°C. The technique 0 is used to assess the crystallinity of the polymers. The results are quoted as "A" for polymers that showed no significant crystallinity i.e. are substantially amorphous. Birefringence (BR) - was measured on an Ehrinhaus Compensator taking 5 measurements with both the 633 and 1302nm lasers. The results are quoted in nm. Synthesis Examples - Preparation of monomers Example SE1 9,10,ll,12-dibenzotetracyclo[6.2.2.1 3 ' 6 .0 2 - 7 ]trideca-4,9,ll-triene (DBTCT) was synthesised as follows: A glass lined autoclave was charged with norbornadiene (147.2 g; 1.6 mol), anthracene (71.2 g, 0.4 mol) and hydroquinone (0.8 g - free radical inhibitor) pressurised with nitrogen to 75 Bar (7.5 MPa), heated to 185°C and maintained at this temperature for 20 hours. The autoclave SUBSTITUTE SHEET was allowed to cool and the pressure was released. Unreacted (excess) norbornadiene was removed by distillation and the solid product was recrystallised to give 69 g (642 of theory) of DBTCT. The structure of the monomer was confirmed as the exo-isomer of the title compound by -E nmr mass spectrometry and IR analysis. Example SE2 Synthesis of l-methyl-9,10,11,12-dibenzotetracyclo[6.2.2.1 3 » 6 .0 2 • 7 ]- trideca-4,9,ll-triene (MDBTCT). The title compound was made by the general method of Example SEl but using 9-methylanthracene instead of the anthracene used in Example SEl. The structure of the monomer was confirmed as the exo-isomer of the title compound by -E nmr mass spectrometry and IR analysis. Example SE3 Synthesis of 1,8-dichloro-9,10,11,12-dibenzotetracyclo[6.2.2.1 3 » 6 .0 2 • 7 ]- trideca-4,9,ll-triene (DCDBTCT). The title compound was made by the general method of Example SEl but using 9,10-dichloroanthracene instead of the anthracene used in Example SEl. The structure of the monomer was confirmed as the exo-isomer of the title compound by -E nmr mass spectrometry and IR analysis. Example SE4 Synthesis of 10,11,12,13-dibenzotricyclo[8.2.2.0 2 « 9 ]tetradeca- 5,10,12-triene (DBTTT). The title compound was made by the general method of Example SEl but using 1,5-cyclooctadiene instead of the norbornene used in Example SEl. The structure of the monomer was confirmed as the exo-isomer of the title compound by -E nmr mass spectrometry and IR analysis. Example 1 - Preparation of copolymers with ethylene A norbornene type monomer (DBTCT) was copolymerised with ethylene as follows: SUBSTITUTE SHEET A 1 litre flanged glass reactor fitted with a mechanical stirrer, a gas inlet dispersion tube, a thermometer and a dropping funnel was used as the polymerisation vessel. The vessel was thoroughly purged and provided with an atmosphere of dry nitrogen, charged with dry toluene (250 ml), the DBTCT and DEAC as the aluminium alkyl co-catalyst, and the dropping funnel was charged with the vanadium(III)acetylacetonate [V(acac)3] catalyst in dry toluene (25 ml) in the amounts set out in Table 1 below. The vessel was cooled to the required temperature and a mixture of nitrogen, at a flow rate of 36 l.h" 1 , and ethylene, at the flow rate set out in Table 1, were passed through the solution in the vessel for 10 min. The polymerisation reaction was then initiated by starting to add the vanadium catalyst solution from the dropping funnel. The catalyst solution was added gradually to the reaction mixture over the reaction period. The nitrogen/ethylene gas flow rate was maintained for the reaction times and temperature as set out in Table la below. A few minutes after the completion of the catalyst solution addition, the reaction was then terminated by adding methanol (5 ml). The copolymer was recovered by adding the reaction mix to a large excess of methanol (containing 0.52 by volume of 1M HC1 and a small quantity of 2-t.-butyl- 4-methylphenol as antioxidant) and separating the precipitated copolymer, which was washed sequentially with methanol then with acetone and then dried in vacuo (overnight). The intrinsic viscosity, ethylene content, Tg, water absorption, XRD Analysis and birefringence were determined as described above and the results are set out in Table 2 below. Examples 2 and 3 These Examples are repeats of Example 1 except that dichloroethoxy- oxovanadium [V0(0Et)Cl2] was used as the vanadium catalyst and the amounts of vanadium catalyst and the DEAC aluminium alkyl co-catalyst used are as set out in Table 1. The results of testing the copolymer products are included in Table 2. Example k Example 2 was repeated except that 302 by weight of the DBTCT monomer was dissolved in the dry toluene with the DEAC aluminium alkyl co-catalysr in the reactor and the remaining 702 by weight was included with the vanadium catalyst in the solution in the dropping funnel. The amounts of vanadium catalyst and the DEAC aluminium alkyl co-catalyst used are as set out in Table 1. Polymerisation was initiated by starting to add the vanadium catalyst and DBTCT solution in the dropping funnel to the solution in the reactor. The results of testing the copolymer product are included in Table 2. Example 5 " Z Example 4 was repeated except that EASC was used as the aluminium alkyl co-catalyst. The results of testing the copolymer product are included in Table 2. Example 6 Example 4 was repeated except that 302 by weight of the DBTCT monomer was dissolved in the dry toluene with the vanadium catalyst in the reactor and the remaining 702 by weight was included with in the solution in the dropping funnel the aluminium alkyl co-catalyst. Polymerisation 20 was initiated by starting to add the aluminium alkyl co-catalyst and DBTCT solution in the dropping funnel to the solution in the reactor. The results of testing the copolymer product are included in Table 2. Examples 7 Example 6 was repeated but with the process variations set out in Table 1. The results of testing the copolymer products are included in Table 2. 22 Examples 8 Example 6 was repeated but using EASC as the aluminium alkyl co-catalyst. The results of testing the copolymer products are included in Table 2. Example 9 Example 2 was repeated but using a reactor equipped with two dropping SUBSTITUTE SHEET funnels. In the synthesis, some of the DBTCT monomer and the vanadium catalyst (0.2 mmole) were put in the reactor and the EASC aluminium alkyl co-catalyst (0.1 mmole) dissolved in dry toluene (80 ml) was placed in one dropping funnel and the remainder of the DBTCT monomer dissolved in dry toluene (80 ml) was placed in the other dropping funnel, with amounts of DBTCT monomer in the reactor and the second dropping funnel set out in Table 3 below (the DBCTC is indicated as monomer I in the Table). The reactor was cooled to a reaction temperature of 12°C purged using nitrogen (at 36 l.hr"***-) and ethylene at a flow rate of 9.6 l.hr -1 . The polymerisation was initiated by starting to add the EASC solution from the dropping funnel. The DBTCT monomer from the second dropping funnel was added gradually over the reaction period of 30 minutes. The results of testing the copolymer product are set out in Table 4 below. Example 10 Example 9 was repeated but using the amounts of monomer in the reactor and second dropping funnel set out in Table 3 and an ethylene flow rate of 10.8 l.hr -1 . The results of testing the copolymer product are included in Table 4. Example 11 Example 9 was repeated but using MDBTCT as the norbornene type monomer and using the amounts of monomer in the reactor and second dropping funnel set out in Table 3. The results of testing the copolymer product are included in Table 4. Example 12 Example 9 was repeated but using a combination of DBTCT and norbornene as the norbornene type monomers to produce a terpolymer product. The amounts of the monomers used in the reactor and second dropping funnel are set out in Table 3 (the DBCTC is indicated as monomer I and the norbornene as monomer II in the Table). The results of testing the copolymer product are included in Table 4. SUBSTITUTESHEET Example 13 Example 12 was repeated but using DCDBTCT and norbornene as the norbornene type monomers and using the amounts of the monomers in the 5 reactor and second dropping funnel set out in Table 3. The results of testing the copolymer product are included in Table 4. Example 14 " 2 Example 12 was repeated but using DBTTT and norbornene as the norbornene type monomers and using the amounts of the monomers in the reactor and second dropping funnel set out in Table 3. The results of testing the copolymer product are included in Table 4. ' 5 Example 15 Example 9 was repeated but using a combination of ethylene and propylene as the acyclic olefin monomers to produce a terpolymer product. The amounts of the DBTCT monomer used in the reactor and second dropping 22 funnel are set out in Table 3 and 40 ml dry toluene was used as the solvent for the EASC used as the aluminium alkyl co-catalyst in the first dropping funnel. The results of testing the copolymer product are included in Table 4. 2 Examples 16 and 17 These Examples repeated Example 15 with the process variations set out in Table 3. The results of testing the copolymer products are included in Table 4. SUBSTITUTE SHEET Table 1 Table 2 : Table- 3 SUBSTITUTE SHEET Table 4 Table 5 Table 6 SUBSTITUTE SHEET

Claims: Claims : An amorphous polymer containing units derived from an acyclic mono-olefin and units derived from a norbornene type olefin including units of the formula (I): where: i is 0, 1 or 2, 112 is 0 or 1 and i + n2 > 0; 3 is 0 or from 1 to 4; is 0 or from 1 to 4; each Rl, each R 2 and each R 3 , is independently a hydrogen or halogen atom, or an alkyl, cycloalkyl, aralkyl, alkaryl or aryl group; the ring group Al is 1,2-cyclohexylene or a 1,2-phenylene group which may be unsubstituted or substituted with one or more halogen atoms, alkyl or aryl groups and may have further 1,2-cyclohexylene or a 1,2-phenylene ring group(s) respectively fused to it. An amorphous polymer as claimed in claim 1 in which halogen atoms are chlorine atoms; alkyl groups are C*^ to C4 alkyl groups; cycloalkyl groups are cyclohexyl groups; alkenyl groups are C2 to C5 alkenyl groups; alkynyl groups are C2 to C5 alkynyl groups; aralkyl groups are phenyl substituted Ci to C4 alkyl groups; alkaryl groups are C * j_ to C alkyl substituted phenyl groups; and aryl groups are phenyl groups, which alkyl, cycloalkyl, aralkyl, alkaryl or aryl groups or substituents can be further substituted with halogen atoms, alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl, alkaryl or aryl groups. SUBSTITUTESHEET An amorphous polymer as claimed in either claim 1 or claim 2 including repeating units of at least one of the formulae (I) a to c: (I)a (when n * j_ is 0 and n2 is 1): (I)b when ni is 1 or more and 2 is 0; (I)c when ni is 1 or more and 2 is 1: SUBSTITUTESHEET An amorphous polymer as claimed in claim 3 wherein the ring A 3 is a cyclobutenylene (n3-n =0) , cyclopentenylene (n3=l, 4=0), cyclohexenylene ( 3= 4=l), or cyclooctenylnene (n3=*n =2) , ring, An amorphous polymer as claimed in any one of claims 1 to 4 wherein the units derived from a norbornene type olefin include units derived from norbornene, alkyl substituted norbornenes, particularly 5-methylnorbornene and 6-methyl-l,4,5,8-dimethano- l,4,4a,5,6,7,8,8a-octahydronaphthalene or units of the reduced residues of dicyclopentadiene or ethylidene norbornene. An amorphous polymer as claimed in any one of claims 1 to 5 wherein the units derived from the norbornene type olefin comprise from about 10 to to 60 mole 2 and units derived from the acyclic mono-olefin comprise from about 90 to 40 mole 2 of the amorphous copolymer. An amorphous polymer as claimed in claim 6 wherein the units derived from the norbornene type olefin comprise from about 15 to 40 mole 2 and units derived from the acyclic mono-olefin comprise from about 85 to 60 mole 2 of the amorphous copolymer. An amorphous polymer as claimed in any one of claims 1 to 7 wherein the at least 252 of the units derived from the norbornene type olefin are units of the formula (I) as defined in any one of claims 1 to . An amorphous polymer as claimed in any one of claims 1 to 8 wherein the units derived from the acyclic mono-olefin are units derived from ethylene and/or propylene. An amorphous polymer as claimed in claim 9 comprising from 85 to 60 mole 2 of units derived from ethylene. A method of making an amorphous copolymer as claimed in any one of claims 1 to 10 which comprises, polymerising a mixture of at least one acyclic mono-olefin and at least one monomer of the formula (II): where: (I)b Ω. , 2, 3, and 4 are each, independently, as defined for formula (I) in claim 1; each l, each R 2 , each R 3 , is, independently, as defined for formula (I) in claim 1, or is an alkenyl group or an alkynyl group; and ring group A 2 is a 1,2-phenylene ring group which may be unsubstituted or substituted with one or more halogen atoms, alkyl or aryl groups and may have further 1,2-phenylene ring group(s) fused to it; and, if necessary, hydrogenating the polymer. An optical component comprising an amorphous polyolefin as claimed in any one of claims 1 to 10 or made by the method of claim 11 An optical component as claimed in claim 12 in the form of an optical disc or optical fibre. SUBSTITUTE SHEET

Inventors: WILSON BRIAN, WILSON, BRIAN
Applicants: ICI PLC, IMPERIAL CHEMICAL INDUSTRIES PLC
Application year: 1991
Main classification: C08F232
IPC codes: C08F210