GB2456828A

GB2456828A - Emulsion of maleic anhydride grafted propylene based elastomer

Info

Publication number: GB2456828A
Application number: GB0801489A
Authority: GB
Inventors: Paul Cornelle De May; Guy Joseph Wouters
Original assignee: ExxonMobil Chemical Patents Inc
Current assignee: ExxonMobil Chemical Patents Inc
Priority date: 2008-01-28
Filing date: 2008-01-28
Publication date: 2009-07-29
Also published as: GB0801489D0

Abstract

A water-based emulsion comprising water diluent and emulsified therein particles comprising a maleic anhydride functionalised grafted propylene based elastomer having an isotactic triad fraction as determined by NMR from 40-99% and a heat fusion as determined by DSC of less than 70 J/g. Also disclosed is a water-based emulsion comprising water diluent and emulsified therein from 5-70 wt% of particles comprising a maleic anhydride functionalised grafted propylene based elastomer having a Melt Flow Rate of 20-400 g/10min (1.2 Kg @ 190{C), a polypropylene content of 65-95 mol% and a balance of ethylene derived units, an isotactic triad fraction as determined by NMR from 40-99% and a heat fusion as determined by DSC of less than 70 J/g and a melting point less than 105{C and 0.2-1.5 wt% based on the total weight of the grafted polymer of maleic anhydride derived units; and use of the water-based emulsions as surface coating.

Description

2008EM022 GB -1-2456828

ADHESIVE EMULSIONS OF MALEIC ANHYDRIDE GRAFFED PROPYLENE

BASED ELASTOMERS

FIELD OF THE INVENTION

10001] The invention relates to adhesive emulsions of maleic anhydride grafted propylene based elastomers, and more particularly water based emulsions useful for surface coatings produced by emulsifying maleic anhydride grafted propylene based elastomers having an isotactic triad content of from 65 % to 99 %.

BACKGROUND

100021 Polyolefin feedstock has been grafted using appropriate initiators with maleic anhydride to introduce oxygen containing moieties in side chains to enhance adhesive properties or to serve as a functional group for further reaction with for example an amide. The functionalized polyolefin may be applied to the surface of various substrates including for example paper, textiles, metals, glass, glass fibers and plastics to modify their properties, including especially surface polarity and adhesion.

[00031 Grafted polyolefins have been applied onto substrates in solution with a volatile solvent by coating or spraying and subsequent drying. The evaporation into air of the solvent may be environmentally damaging. Grafted polyolefins have also been emulsified in water using appropriate techniques and are less environmentally damaging. The water diluent is drained and evaporated and the emulsified particles coalesce to form a coating. * *.

[00041 A wide variety of different polyolefins have been functionalized. Ethylene based polymers, which term is used herein to indicate a polymer having at least 5Owt% of the polymer * : derived from ethylene, has been grafted with maleic anhydride for using as an adhesive coating or tie-layer; and lower density ethylene based elastomers have been used as a compatibilizer for blends in which the impact properties of polyamides are modified by adding an ethylene *". : propylene rubber.

* [0005) Propylene based polymers, which term is used herein to indicate that at least 5Owt% of the polymer is derived from propylene, have been grafted for certain adhesive coating uses requiring compatibility with crystalline isotactic polypropylene and another more polar material or as a compatibilizer in blends in which the impact properties of polypropylene are modified by the inclusion of a small amount of an ethylene-propylene rubber. The term "isotactic" as in isotactic polypropylene is defined herein as a polymer sequence in which greater than 50% of 2008EM022 GB the pairs of pendant methyl groups located on adjacent propylene units, which are inserted into the chain in a regio regular 1,2 fashion and are not part of the backbone structure, are located either above or below the atoms in the backbone chain, when such atoms in the backbone chain are all in one plane.

100061 US2005/124753 describes aqueous emulsions of maleic anhydride grafted isotactic polypropylene homopolymer (abbreviated herein as Ma-g-iPP) and maleic anhydride grafted propylene random copolymer (abbreviated herein as Ma-g-RCP) as suitable for coating polypropylene composites. The base iPP or RCP used as the feedstock may have a propylene content of at least 90 mole % and an isotactic pentad content of 10 to 60 %.

100071 US2006/00691 87 describes functional polypropylene based emulsions suitable for the sizing of glass fibers and processes to make the emulsions. US5574091 and US5798410 describe emulsions of substantially linear ethylene copolymers with octene and butene free of polar groups made by direct emulsification of the polymer solutions in a suitable solvent followed by solvent evaporation.

[00081 The level of functionality that can be achieved for a given molecular weight in functionalizing polypropylenes is limited by the -scissioning effect of the peroxide used to graft the maleic anhydride onto the polypropylene, see Eastman EP777693-B 1. The polypropylene backbone may be scissioned at the grafting location resulting in a simultaneously reduction in molecular weight and a placement of the functionality at the end of the polymer chain that is broken off. In addition the grafted polypropylenes tend to be stiff and brittle. This limits the usefulness of such functionalized materials in coatings.

*... [00091 Functionalized propylene based elastomers are described in US6884850 *q.

(W02002136651). When maleated a high grafting level may be achieved while the isotactic * sequences are sufficiently long to engender crystallinity. However there is no suggestion for application as part of an emulsion.

[00101 US2005/0271888 discloses the use of maleic anhydride grafted propylene based :::: : elastomers in adhesive formulations. Tackifier is generally included. No reference is made to * the possible emulsification of such formulations.

[00111 Grafted ungrafted propylene based elastomers are described in US2006/0293424 but not their use in water-based emulsions (see paragraph [0245]. The adhesive discussed may contain one or more of a combination of components as set out in [0302] but the use in an aqueous emulsion is not disclosed.

2008EM022 GB

SUMMARY OF THE INVENTION

[00121 The invention provides a stable aqueous emulsions, capable of forming thin films after evaporization of the diluent, of film forming propylene based elastomers having higher functionality and flexibility than can be produced using functional polypropylene polymers such as those described in US6884850. The emulsions may be used for coating a polypropylene substrate and permit adhesion of a non-polyolefinic material such a polymer having polar moieties (polyamide; polyester, glass or metal).

10013) Propylene based elastomers having isotactic sequences can reach a low heat of fusion at the level generally associated with elastomers by using low amounts of comonomer and by selecting the catalyst and process to promote steric irregularity in the propylene sequences in the polymer backbone.

[00141 The invention surprisingly permits a combination of features that make aqueous emulsions especially effective in that they combine a relatively high molecular weight with a relatively high degree of functionality and the propylene content and tacticity remains sufficiently high for good compatibility with polypropylene substrates having a higher tacticity and enough flexibility to maintain the adhesive bonds formed when deformed.

[0015] The adhesive layer formed after coating the emulsion onto a substrate has a lower melting temperature allowing sealing at a lower temperature than traditional functionalized polypropylene. Such emulsions can also provide a chlorine free adhesive system, replacing emulsions of chlorinated polypropylene or maleic acid grafted chlorinated polypropylene.

100161 The invention may be applied to propylene based elastomers that are relatively homogenous as far as molecular weight, composition distribution and sequence distribution are concerned or to propylene based elastomer having a relatively broad molecular weight r distribution, a relatively broad composition distribution as may be determined by Crystaf measurement or solvent fractionation, and/or have fairly blocky sequence distribution, that may approximate the structure of block copolymers. The increased length of stereoregular propylene * * . ** U * based sequences may lead to the presence of a more elevated melting point.

[0017] The functional polymers are produced according to US68 84850 by functionalizing a polymer backbone with an unsaturated compound having a polar group where the polymer backbone is a propylene based polymer having an isotactic triad fraction from about 65 % to about 99 % based on 13C NMR measurement. Preferably, the polymer has a crystallinity of from 0.1 to 50 wt% from isotactic polypropylene sequences, preferably propylene content of 2008EM022 GB from 68 to 92 mole %, and a heat of fusion determined by DSC of less than 70 JIg and a melting point of from 25 to 105C.

100181 The polymer backbone is a propylene copolymer with C2 or a C4-C20 alpha-olefin. The polymer may firstly be a propylene-ethylene copolymer, and may further include non conjugated dienes such as those described in US2005-0 107534. In this case the compositional distribution may be relatively homogeneous. The polymer may also be a mixture of polymers of different composition or steric configuration with a relatively heterogeneous composition distribution.

[0019J Preferably, the unsaturated compound used to functionalize the polymer has a carboxylic anhydride or carboxylic acid functionality. Most preferably, the unsaturated compound is maleic anhydride. Carboxylic ester functionality like glycidyl methacrylate is also of interest for improving adhesion between polypropylene based surfaces and other poiar surfaces like for examples plastic surfaces containing reactive groups like polyamides or polyesters.

[0020J The polymer can be emulsified by a direct or an inverse emulsification process via a batch, semi batch or continuous emulsification process in the presence of a surfactant or mixtures of surfactants and water. Preferably the emulsification is performed to minimize the presence of solvents. The polymer is melted and brought to an elevated temperature where the viscosity is low and then subjected to shear in the presence of the emulsion diluent and other agents to promote emulsification or to maintain the stability of the emulsion after the temperature returns to ambient.

100211 The emulsification can be carried out at ambient or elevated temperature via a batch or eq.:. semi-batch process in a pressurized reactor equipped and shear can be provided by suitable "p mixing devices like for example propellers or turbines agitators. If the viscosity of the molten * :e1 polymer is too high to perform the emulsification at the desired emulsification process temperature, it can be reduced via addition of oil or a solvent. After emulsification, the solvent can be removed by distillation or stripping.

:: : [00221 Direct emulsification of a polymer solution is described in US3503917. Example of * direct emulsification process of a maleic anhydride grafted polypropylene polymer in a pressurized reactor is given in US6818698 and in US patent application 2004-0229985. The polymer or polymer solution can be emulsified via a continuous emulsification process using static mixers placed in series as described in EP283247. This process can use either the molten polymer or a solution of the polymer is a suitable solvent, or polymer mixed with a plasticizer like hydrocarbon oil.

2008EM022 GB 100231 Another process aiming at emulsifying molten polymers via a melt kneading process is described in W02005/102 1638. Another continuous process aiming at emulsifying a polymer solution using high shear mixing devices is described in US553902 1. A continuous inverse emulsification process is described for example in US4423403.

[00241 Emulsions having a particle size below 1 micron (1000 nm) and most preferably below 700 nm are preferred. Other additives can also be present. Anionic, cationic or non-ionic surfactants as well as blends thereof can be used to emulsify the functional propylene polymers.

Anionic surfactants especially suitable are the sodium or potassium or ammonium salts of alkyl or alkyl-aryl ethers of polyethylene oxide sulfates or sulfonates or phosphates, and the sodium or potassium or ammonium salts of alkyl esters of sulfosuccinic acid like sodium di-(2-ethylhexyl)-sulfosuccjnate. Other suitable anionic surfactants include metal or ammonium salts of fatty acids, and metal or aminonium salts of alkyl or aryl sulfates and sulfonates. Especially suitable non-ionic surfactants comprise esters and ethers of polyethylene oxide, like fatty acid esters and alkyl or alkyl-aryl ethers.

[00251 The acid or anhydride functionality of the propylene based polymer can be partly neutralized with a base like sodium or potassium hydroxide or with ammonia, or with an organic amine. This partial neutralization can facilitate the emulsification of the polymer and improve the stability of the emulsion. Other additives like pH modifiers, de-foamers, thickeners, fungicides etc. can also be used.

ProDylene based elastomers [00261 As used herein, "polymer" may be used to refer to homopolymers, copolymers, * .S.

interpolymers, etc. Likewise, a "copolymer" may refer to a polymer comprising two monomers orto a polymer comprising three or more monomers. Propylene based elastomeric polymers are produced by polymerization processes leading to polymers having randomly distributed non-stereoregular sequences between sequences with stereoregular propylene propagation. The non- :::: : stereoregular sequences may be of atactically arranged chiral monomers such a propylene or a * higher aipha-olefin or may be of ethylene based sequences starting with a single unit and ending at the top end with sequences long enough to permit some ethylenic crystallization.

[00271 The term "elastomeric polymer" indicates that the heat of fusion of the polymer as determined by DSC is less than 70 J/g but with sufficient levels of crystallinity to provide for recovery from elastic deformation.

2008EM022 GB [0028] The polymer is "propylene based" in the sense that the amount of propylene in the polymer is sufficient for propylene sequences to crystallize to give rise to a detectable heat of fusion. This is in contrast with known elastomeric polymers based on ethylene and propylene in which the heat of fusion can be attributed to ethylene derived polymer sequences only.

Preferably the polymers contain isotactic propylene sequences, separated by stereo or regio error or by one or more units from a comonomer. Exemplary polymers include US6881 800B2, W0200203665 I Al, W02003040201 Al, US6525 1 57B2, US67707 1 3B2, US200502 I 5964A1, EP 161 4699A 1, EP 101 7729A2, EP 1561 762A 1 and EP 1002 809A 1.. As used herein, "propylene-based polymer backbone" is defined to be a polymer comprising propylene and one or more C2 and/or C4-C20 alpha olefins, propylene being the major component. As used herein, "isotactic" is defined as polymeric stereoregularity having at least 40% isotactic pentads of methyl groups derived from propylene according to analysis by 3C-NMR (Nuclear Magnetic Resonance).

[0029) The polymers and compositions described herein can be characterized in terms of their melting points (Tm) and heats of fusion, which properties can be influenced by the presence of comonorners or steric irregularities that hinder the formation of crystallites by the polymer chains. The heat of fusion preferably ranges from a lower limit of 1.0 JIg, or 1.5 JIg, or 3.0 JIg, or 4.0 JIg, or 6.0 JIg, or 7.0 JIg, to an upper limit of 30 JIg, or 40 JIg or 60 J/g. Here and every where else any lower range end may be combined with an upper range end to provide alternative ranges. If the heat of fusion is too high, the coating may be insufficiently flexible to maintain good adhesion. If the heat of fusion is too low the coating may lack strength.

[0030) The heat of fusion can be reduced by using additional comonomer, higher polymerization temperatures and/or a different catalyst providing reduced levels of steric * constraints and favoring more propagation errors for propylene insertion.

[0031) The isotactic triad tacticity may be from 65 % to about 99 %. Advantageously the *...

* 25 propylene-derived units have a triad tacticity of 70 % to 98 or 75 % to 97%. If the triad tacticity is too high, the level of stereo-irregular disruption of the chain may be too low and the elastic properties will suffer. If the triad tacticity is too low, there is insufficient potential for adhesive strength. The triad tacticity and tacticity index may be controlled by the catalyst influencing the S...

: stereoregulaxity of propylene placement, the polymerization temperature according to which * :* .o stereoregularity can be reduced by increasing the temperature and by the type and amount of a comonomer which tends to disrupt reduce the level of longer propylene derived sequences.

2008EM022 GB [00321 Preferably the polymer contains at least some comonomer, such as an aipha-olefin, in order to facilitate control of the structure. Preferably the comonomer comprises substantially ethylene which can aid in achieving economic polymerization conditions by raising the molecular weight and/or permitting a raising of the polymerization temperature. Generally the amount of the ethylene or alpha-olefin combined varies from 5 to 30 wt %, preferably from 10 to 20 weight percent and especially from 12 to 20 wt%. Too much comonomer will reduce the crystallinity provided by the crystallization of stereoregular propylene derived sequences to the point where the material lacks elastic recovery; too little and the material will be too crystalline, have a high melting point and be insufficiently elastic.

[0033) The polymer may also contain polyenes to facilitate functionalization and/or cross-linking. The polymer may incorporate from 1 wt. % to 12 wt. % of polyene-derived units.

Preferably the polymer incorporates from 1.0 wt. % to about 9.0 wt. % of polyene-derived units.

The polyene-derived units may be derived from a diene such as 5-ethylidene-2-norbomene which has one polymerizable bond that can be incorporated during polymerization and is not prone to branch formation because the other group is not so polymerizable. The polyene may also be a diene such as 5-vinyl-2-norbomene or divinyl benzene in which both bonds can polymerize and long chain branches can be produced.

[0034) The amount of the polyene present in the polymeric components can be inferred by the quantitative measure of the amount of the pendent free olefin present in the polymer after polymerization. Several procedures such as iodine number and the determination of the olefin content by 1H or 13C NMR have been established. In the particular case where the polyene is ENB the amount of polyene present in the polymers can be measured using ASTM D3900.

[0035) The propylene-based polymer backbone may comprise propylene, one or more C2 .. and/or C4-C20 alpha olefins. The propylene based polymer may be a hetero-phasic polymer *:::: having an isotactic PP phase and a dispersed rubber phase without propylene derived isotacticity. The propylene-based polymer backbone may have a DSC melting point of 120°C or less, preferably 115°C or less, more preferably 105°C or less, more preferably 100°C or less, more preferably 90°C or less, more preferably t 85°C or less, and most preferably 75°C *: : :: or less, and a heat of fusion of preferably about 65 JIg or less, and most preferably about 60 **** J/g or less. The elastomer may have at least one melting peak as determined by DSC below °C. The propylene-based polymer backbone is preferably a propylene-ethylene copolymer, preferably with a propylene content of at least about 75 wt% and ethylene content in the range of 4 wt% to 25 wt%, more preferably 5 to 24 wt%, more preferably 7 to 20 wt%, 2008EM022 GB more preferably 7 to about 16 wt%, and most preferably 8 to 15 wt%. In further embodiments, the propylene-based polymer backbone preferably may comprise a suitable grade of VISTAMAXXTM elastomer (ExxonMobil Chemical Company, Baytown, TX, USA), a suitable grade of VERSIFYTM polymer (The Dow Chemical Company, Midland, Michigan, USA), a suitable grade of Tafmer XM or a suitable grade of NotiolM (The Mitsui Company of Japan), or a suitable grade of Softel (Basell Company of the Netherlands).

[00361 The propylene-based polymer backbone may include copolymers prepared according the procedures in WO 02/36651, which is incorporated by reference here. Likewise, the propylene-based polymer backbone can include polymers consistent with those described in WO 03/040201, WO 03/040202, WO 03/040095, WO 03/040201, WO 03/040233, and/or WO 03/040442. Additionally, the propylene-based polymer backbone can include polymers consistent with those described in European Patent No. 1 233 191, and U.S. Patent No. 6,525,157, along with suitable propylene homo-and co-polymers described in U.S. Patent No. 6,770,713 and U.S. Patent Application Publication No. 2005/0215964, all of which are incorporated herein by reference. The propylene-based polymer backbone can also include one or more polymers consistent with those described in European Patent Nos. 1,614,699; 1,017,729; 1,561,762 or 1,002,809.

[0037] The catalyst may also control the stereoregularity in combination with the comonomer and the polymerization temperature. The catalyst should however be capable of a level of stereoregular placement, generally by suitable chirality of the single site catalyst. The polymer can be prepared using any single sited catalyst. Such a catalyst may be a transition metal complex generally containing a transition metal Groups 3 to 10 of the Periodic Table; and at least one ancillary ligand that remains bonded to the transition metal during polymerization. * *S

* ** Preferably the transition metal is used in a reduced cationic state and stabilized by a cocatalyst *...25 oractivator.

100381 The ancillary ligand may be a structure capable of forming a it bond such a * ***** * 1 cyclopentadienyl type ring structure, see EP284708. The ancillary ligand may also be a pyridinyl or amide ligand, see W003/04020 1. The transition metal complex may a flux ional complex, which undergoes periodic intra-molecular re-arrangement so as to provide the desired **.?° interruption of stereoregularity as in US6559262. The transition metal complex may be a stereorigid complex with mixed influence on propylene insertion, see Rieger EP1070087. The transition metal is preferably of Group 4 of the Periodic table such as titanium, hafnium or zirconium which is used in polymerization in the d° mono-valent cationic state and have one or 2008EM022 GB two ancillary ligands as described in more detail hereafter. The important features of such catalysts for coordination polymerization are the ligand capable of abstraction and that ligand into which the ethylene (olefinic) group can be inserted.

10039) The manner of activation of the single site catalyst can vary. Methyl alumoxane non-or weakly coordinating anion activators (NCA) may be used. When using the catalysts, the total catalyst system will generally additionally comprise one or more organo-metallic compound as scavenger. Such compounds as used in this application is meant to include those compounds effective for removing polar impurities from the reaction environment and for increasing catalyst activity. The polymerization reaction is conducted homogeneously, such as by a continuous solution process or a bulk polymerization process with excess monomer used as diluent.

[0040) The propylene based elastomer preferably has an MFR of 0.5 to 200, especially from 1 to 100 or more especially 1 to 50. The molecular weight distribution MIM (MWD), sometimes referred to as a "polydispersity index' (PDI), may be within the range having an upper limit of 40, or 20, or 10, or 5, or 4.5, and a lower limit of 1.5, or 1.8, or 2.0.

Test Drotocols 10041] The isotactic triad content was determined as described in Isotactic triad content. The "triad tacticity" of the polymers described herein can be determined from a 3C nuclear magnetic resonance (NMR) spectrum of the polymer as described in U.S. Patent No. 5,504,172, and U.S. Patent No. 6,642,316, column 6, lines 38 through column 9, line 18, which patents are hereby incorporated by reference in their entirety. To measure the 3C NMR spectrum, 250-350 mg of polymer is completely dissolved in deuterated tetrachloroethane in a 10 mm diameter . NMR sample tube at 120°C. The measurement is conducted with full proton decoupling using a 900 pulse angle and at least a 15 second delay between pulses. Calculations involved in the characterization of polymers by NMR follow the work of F. A. Bovey in "Polymer * Conformation and Configuration" Academic Press, New York 1969 and J. Randall in "Polymer Sequence Determination, Carbon-13 NMR Method", Academic Press, New York, 1977.

: Assignments were based on H. N. Cheng and J. A. Ewen, Makromol. Chem. 1989, 190, 1931.

With respect to measuring the chemical shifts of the resonances, the methyl group of the third unit in a sequence of 5 contiguous propylene units consisting of head-to-tail bonds and having the same relative chirality is set to 21.83 ppm. The chemical shift of other carbon resonances are determined by using the above-mentioned value as a reference. The spectrum relating to the 2008EM022 GB methyl carbon region (17.0-23.0 ppm) can be classified into the first region (21.1-21.9 ppm), the second region (20,4-21.0 ppm), the third region (19.5.20.4 ppm), and the fourth region (17.0-17.5 ppm). Each peak in the spectrum was assigned with reference to a literature source, such as "Polymer," 30 (1989) 1350 or "Macromolecules," 17 (1984) 1940, which are hereby fully incorporated herein by reference. In the first region, the methyl group of the center unit in a PPP (mm) triad resonates. In the second region, the methyl group of the center unit in a PPP (mr) triad resonates. In the third region, the methyl group of the center unit in a PPP (rr) resonates. The nun' tacticity of the polymer can then be determined using the 3C NMR spectrum of the polymer and the following formula: PPP(mm) mm Fraction PPP(mm) + PPP(mr) + PPP(rr) where PPP(min), PPP(mr) and PPP(rr) denote peak areas derived from the methyl groups of the second units in the following three propylene unit chains consisting of head-to-tail bonds: CH3 CH3 CH3 PPP(mm): (H -CH2HH -CH2HH -CH2 CH3 CH3 PPP(mr): (L_CH2HHCH2HCH_CH2 CH3 * ** * . S * *e CH3 CH3 S...

* : PPP(rr): (H-CH2HCH_CH2HH_CH2H CH3 *:::: The peak areas used in the above calculation are not measured directly from the triad regions in * * : the 3C NMR spectrum. The areas due to errors in propylene insertions must be subtracted from the intensities of the second (mr) region and third (rr) region, as explained in the discussion which follows. The insertion of propylene can occur to a small extent by either 2,1 (tail to tail) or 1,3 (end to end). Examples of 2,1 insertion are shown in structures 1 and 2 below.

2008EM022 GB Structure (1):

A B A

CH3 CH3 CH3 CH3 CH3 ___f(H-CH2)_L-CH2)_(CH2_.4H)__(CH2_CH2)_((L CH2H(L-CH2)___ Structure (2): A' B' A' CH3 CH3 CH3 CH3 CH3 __4i___CH2HL_CH2HCH2_JH)__fCH2_CH2)_(cL CH2)_L_CH2)___ wheren�=2.

[00421 A peak of the carbon A and a peak of the carbon A' appear in the second region. A peak of the carbon B and a peak of the carbon B' appear in the third region. Among the peaks which appear in the first to third regions, peaks which are not based on the 3 propylene unit chain consisting of head-to-tail bonds are peaks based on the PPE-methyl group, the EPE-methyl group, the carbon A, the carbon A', the carbon B, and the carbon B'.

100431 The peak area based on the PPE-methyl group can be evaluated by the peak area of the PPE-methine group (resonance in the vicinity of 30.8 ppm), and the peak area based on the EPE-methyl group can be evaluated by the peak area of the EPE-methine group (resonance in the vicinity of 33.1 ppm). The peak area based on the carbon A can be evaluated by twice as much as the peak area of the methine carbon (resonance in the vicinity of 33.9 ppm) to which the methyl group of the carbon B is directly bonded; and the peak area based on the carbon A' * ** *, can be evaluated by the peak area of the adjacent methine carbon (resonance in the vicinity of *:::* 33.6 ppm) of the methyl group of the carbon B'. The peak area based on the carbon B can be evaluated by the peak area of the adjacent methine carbon (resonance in the vicinity of 33.9 * ***** * 20 ppm); and the peak area based on the carbon B' can be also evaluated by the adjacent methine carbon (resonance in the vicinity of 33.6 ppm).

*:::: (0044] By subtracting these peak areas from the total peak areas of the second region and the * * third region, the peak areas based on the three propylene unit chains (PPP(mr) and PPP(rr)) consisting of head-to-tail bonds can be obtained. Thus, the peak areas of PPP(mm), PPP(mr) and PPP(rr) can be evaluated, and the triad tacticity of the propylene unit chain consisting of head-to-tail bonds can be determined.

2008EM022 GB 100451 The tacticity index, expressed herein as "m/r", is determined by 3C nuclear magnetic resonance (NMR). The tacticity index mlr is calculated as defined in H.N. Cheng, Macromolecules, 17, 1950 (1984). An m/r ratio of 1.0 generally describes a syndiotactic polymer, and an mlr ratio of 2.0 generally describes an atactic material. An isotactic material theoretically may have a ratio approaching infinity, and many by-product atactic polymers have sufficient isotactic content to result in ratios of greater than 50.

100461 The comonomer content and sequence distribution of the polymers can be measured using 3C nuclear magnetic resonance (NMR) by methods well known to those skilled in the art.

Comonomer content of discrete molecular weight ranges can be measured using methods well known to those skilled in the art, including Fourier Transform Infrared Spectroscopy (FTIR) in conjunction with samples by GPC, as described in Wheeler and Willis, Applied Spectroscopy, 1993, vol. 47, pp. 1128-1130. For a propylene ethylene copolymer containing greater than 75 wt% propylene, the comonomer content (ethylene content) of such a polymer can be measured as follows: A thin homogeneous film is pressed at a temperature of about 150°C or greater, and mounted on a Perkin Elmer PE 1760 infrared spectrophotometer. A full spectrum of the sample from 600 cm1 to 4000 cm1 is recorded and the monomer weight percent of ethylene can be calculated according to the following equation: Ethylene wt% = 82.585 -111.987X + 30.045X2, where X is the ratio of the peak height at 1155 cm' and peak height at either 722 cm or 732 cm, whichever is higher. For propylene ethylene copolymers having 75 wt% or less propylene content, the comonomer (ethylene) content can be measured using the procedure described in the Wheeler and Willis.

100471 The properties can be determined in the description and claims by Differential Scanning Calorimetry (DSC), using the ASTM E-794- 95 (version E-794-01) procedure. About 6 to 10 mg * S. of a sheet of the polymer pressed at approximately 200°C to 230°C is removed with a punch die 0S** and annealed at room temperature for 48 hours. At the end of this period, the sample is placed in a Differential Scanning Calorimeter (Perkin Elmer Pyris Analysis System and cooled to about -50°C to -70°C. The sample is heated at about 20°C/mm to attain a final temperature of about 180°C to 200°C. The term "melting point," as used herein, is the highest peak among S...

* : principal and secondary melting peaks as determined by DSC, discussed above. The thermal *..30 output is recorded as the area under the melting peak of the sample, which is typically at a maximum peak at about 30°C to about 175°C and occurs between the temperatures of about 0°C and about 200°C. The thermal output is measured in Joules as a measure of the heat of 2008EM022 GB -13 -fusion. The temperature of the greatest heat absorption within the range of melting of the sample is recorded as the melting point.

100481 A crystallinity percentage can be calculated from the heat of fusion relative to the heat of fusion of an ideal polypropylene material with maximum crystallinity. For all the materials one or several peaks may be recorded during the heating step. The crystallized propylene sequences in the polymer give rise to a detectable heat of fusion. The polymer contrasts in this respect with known elastomeric polymers based on ethylene and propylene in which the heat of fusion can be attributed to ethylene derived polymer sequences. The initial scan during the heating at 100 C/mm provide the Tm (melting peak) and Mlf (heat of fusion) for the first heating. The subsequent scans can provide the Tc (crystallization peak) and the i.Hc (heat of crystallization) for the cooling step. The total area under the curve between the two integration limits of 20 °C to 140 °C give the heat of fusion (iJ-lt) referred to in the Claims and the Examples. For PP homopolymer Hfl00%=208 Jig. This value can be used to calculate the crystallinity in % if desired. Tthe temperature of the melting peak decreases with co-monomer content.

[0049] The term "MFR" as used herein stands for "Melt Flow Rate" and is used to characterize polymers, components and compositions. The units for "MFR" are grams per 10 minutes and the test to be herein for determining MFR is set forth in any version and condition set forth in ASTM-1238 that uses 2.16 kg. at 230 °C with a 1 minute preheat on the sample to provide a steady temperature for the duration of the experiment. This data expressed as dg of sample extruded per minute is indicated as MFR. In an alternative procedure, the test is conducted in an identical fashion except at a temperature of 190 °C. This data is referred to as MI@190C. MFR: [0050J A molecular weight distribution MfM (MWD), sometimes referred to as a "polydispersity index" (PD!), within the range having an upper limit of 40, or 20, or 10, or 5, or * .* 4.5, and a lower limit of 1.5, or 1.8, or 2.0.The various molecular weight characteristics (e.g., 0S** ....25 Mw and Mn) and molecular weight distribution Mw/Mn (MWD) of the polymer components * (or polymers) described herein can be measured in accordance with the procedures disclosed in * U.S. Patent No. 6,525,157, column 5, lines 1-44, which patent is hereby incorporated by reference in its entirety. Mz, Mw, and Mn can be measured using gel permeation *:: chromatography (GPC), also known as size exclusion chromatography (SEC). This technique utilizes an instrument containing columns packed with porous beads, an elution solvent, and detector in order to separate polymer molecules of different sizes. In a typical measurement, the GPC instrument used is a Waters chromatograph equipped with ultrastyro gel columns operated at 145°C. The elution solvent used is trichlorobenzene. The columns are calibrated using 2008EM022 GB sixteen polystyrene standards of precisely known molecular weights. A correlation of polystyrene retention volume obtained from the standards, to the retention volume of the polymer tested yields the polymer molecular weight. Average molecular weights M can be computed from the expression: M= where N is the number of molecules having a molecular weight M1. When n = 0, M is the number average molecular weight Mn. When n = 1, M is the weight average molecular weight Mw. When n = 2, M is the Z-average molecular weight Mz. The desired MWD function (e.g., MwfMn or Mz/Mw) is the ratio of the corresponding M values. Measurement of M and MWD is well known in the art and is discussed in more detail in, for example, Slade, P. E. Ed., Polymer Molecular Weights Part II, Marcel Dekker, Inc., NY, (1975) 287-368; Rodriguez, F., Principles of Polymer Systems 3rd ed., Hemisphere Pub. Corp., NY, (1989) 155-160; U.s.

Patent No. 4,540,753; Verstrate et a!., Macromolecules, vol. 21, (1988) 3360; and references cited therein.

100511 The maleic anhydride content of the grafted propylene-based polymers was determined according to following procedure. A sample of grafted polymer was first purified from residual monomer by complete solubilization in xylene followed by re-precipitation in acetone. This precipitated polymer was then dried in a vacuum oven at 200° C. for 2 hours in order to convert all maleic acid into anhydride. 0.5 to I grams of re-precipitated polymer was dissolved in 150 mL of toluene. The solution was heated at toluene reflux for 1 hour and 5 drops of a 1% bromothymol blue solution in MeOH were added. The solution was titrated *: with a solution of 0.1 N tetrabutyl ammonium hydroxide in methanol (color change from *:::* yellow to blue). The amount of the tetrabutyl ammonium hydroxide solution used to neutralize the anhydride during the titration was directly proportional to the amount of grafted * ..S.S * 25 maleic anhydride present in the polymer.

[00521 Average particle size is measured with a Malvern Mastersizer 2000 and reported as *: : : number average particle diameter.

100531 Emulsion solids content is measured by weighing up I g emulsion in an aluminum pan and drying 2 hours at 105 °C in a ventilated oven.

2008EM022 GB -15-

Examples

100541 The following materials were used: Ma-g-EPP-1 is a maleic anhydnde grafted propylene-ethylene copolymer having an ethylene content of about 11 wt% and a melting point of about 67 °C. The polymer contains about 0.7 wt% grafted maleic anhydride and has aMFR of 140 g/l0min(l.2 Kg @190 °C).

(00551 MA-g-EPP-2 is a maleic anhydride grafted propylene-ethylene copolymer having an ethylene content of about 16 wt% and a melting point of about 50 °C. The MA-g-polymer contains about 1,1 wt% grafted maleic anhydride and has a MFR of 78 g/l 0mm (1.2 Kg @ 190 °C).

[00561 DOSS is docusate sodium salt (sodium bis-(2-ethylhexyl)-sulfosuccinate) supplied by Sigma-Aldrich and prepared as a 70 wt % solution in ethanol.

100571 NP 40s: is Tergitol� NP 40, a 70 wt % solution in water of octylphenol polyoxyethylene having an average of 40 units of ethylene oxide, manufactured by Union Carbide Chemicals & Plastics Technology Corp. [0058] CA630: is Igepal� CA 630, octylphenol polyoxyethylene having an average of 9 units of ethylene oxide and manufactured by Rhodia Inc. 100591 TDE: is the tridecyl ether of polyoxyethylene having an average of 10 units of ethylene oxide supplied by Sigma-Aldrich.

100601 OPEO2O: is oleyl ester of polyoxyethylene having an average of 20 units of ethylene oxide and supplied by Sigma-Aldrich.

(00611 The emulsion was prepared as follows: g of a 15 wt% solution of maleic anhydride grafted propylene based polymer in toluene is added to 50 g of dc-ionized water containing surfactant as described in Table 1, and mixed for * *I minutes at room temperature with an Ultraturrax T 25 high shear disperser at 20,000 rpm.

*....25 The resulting emulsion is added with water containing optionally additional surfactant as described in Table 2 and stripped from the toluene solvent using a rotary evaporator under *..*** * vacuum at 40 °C. The resulting emulsion is characterized for particle size and solids content as described in Table 2.

: 100621 All emulsions are shelf stable except emulsions of Examples A and H which show some \P creaming after 2 weeks storage at room temperature.

2008EM022 GB

Table I

Example MA-g-EPP Wt toluene Wt water (g) Surfactant Wt% active solution (g) based on toluene solution TEl MA-g-EPP 2 100 50 DOSS 1 TE2 MA-g-EPP 1 100 50 DOSS 1.5 TE3 MA-g-EPP 1 100 50 DOSS 1.5

TDE I

TE4 MA-g-EPP 1 100 50 DOSS 1.51 NP4O TE5 MA-g-EPP 2 100 50 DOSS 1 TE6 MA-g-EPP 2 100 50 DOSS 0.81 CA630 TE7 MA-g-EPP 1 100 50 DOSS 1.5 TE8 MA-g-EPP 1 100 50 DOSS I EPEO2O 0.5 * ** * * * * ** **** * S S... *..*S

S S * 5*5 * .* S. * S. * * SS * *.

2008EM022 GB

Table 2

Toluene free Toluene Added water -Added d average Solids conten emulsion emulsion (g) Surfactant (g) particle size wt%

Examples source (nm)

A TE1/250 50 none 1307 32 B TE2/250 50 CA 630/1.7 1101 31 C TE3/250 50 None 468 30 D TE4/250 50 None 897 33 E TE5/250 50 CA 630/1.7 919 32 F TE6/250 50 none 464 25 U TE7/250 50 OPEO2O/0.5 1040 28 H TE8/250 50 none 1042 28 * .S Is I * ** **** * * S..

I..... * . **S*

S S S S. S *5 * * S S * **

Claims

2008EM022 GB CLAIMS

1. Emulsion comprising water diluent and emulsified therein particles comprising a maleic anhydride functionalized grafted propylene based elastomer having an isotactic triad fraction as determined by NMR from 40 % to 99 % and a heat of fusion as determined by DSC of less than JIg.

2. Emulsion according to Claim 1 in which the elastomer is a copolymer produced by copolymerization of propylene with ethylene or an alpha-olefin having 4 to 12 carbon atoms and optionally a non conjugated diene and/or is a random copolymer having a reactivity ratio rl/r2 less than 1 and a melting point less than 105 °C.

3. Emulsion according to Claim I in which the elastomer is a copolymer produced by copolymerization of propylene with ethylene or an aipha-olefin having 4 to 12 carbon atoms and optionally a non conjugated diene and having a reactivity ratio rl/r2 more than I and a melting point above 105 °C.

4. Emulsion according to any of the preceding claims in which the elastomer has a crystallinity of from 0.1 to 50 wt% due to isotactic polypropylene sequences.

5. Emulsion according to any of the preceding claims in which the elastomer has a propylene content of from 65 to 95 mol %, preferably 75 to 90 mol%.

6. Emulsion according to any of the preceding claims in which the elastomer is blended 0*S S * ....25 with less than 15 wt% based on total polymer content of a propylene based polymer having a melting peak as determined by DSC above 140 °C.

S..... * .

7. Emulsion according to any of the preceding claims in which the elastomer has a Melt *: Flow Rate of from 20 to 400 g/l0min (1.2 Kg @ 190 °C). S. * U * *5

8. Emulsion according to any of the preceding claims in which the elastomer contains from 0.2 to 1.5 wt% based on the total weight of the grafted polymer of maleic anhydride and/or glycidyl-methacrylate derived units.

2008EM022 GB

9. Emulsion according to any of the preceding claims in which the content of the elastomer is from 5 to 70 wt%, preferably more than 25 wt% based on the weight of the emulsion and/or the emulsified particles contain less than 5 wt % of a tackifier and or less than 5 wt% of a wax.

10. Emulsion according to any of the preceding claims in which the particles consists substantially of the malcic anhydride functionalized grafted propylene based elastomer and optionally less than 25 wt% of a polymer component having a higher crystallinity than the propylene based elastomer.

Ii. Emulsion comprising water diluent and emulsified therein from 5 to 70 wt% of particles comprising a maleic anhydride functionalized grafted propylene based elastomer having a Melt Flow Rate of from 20 to 400 g/l 0mm (1.2 Kg @ 190°C), a propylene content of from 65 to 95 mol % and a balance of ethylene derived units, an isotactic triad fraction as determined by NMR from 40 % to 99 % and a heat of fusion as determined by DSC of less than 70 JIg and a melting point less than 105 °C and from 0.2 to 1.5 wt% based on the total weight of the grafted polymer of maleic anhydride derived units.

12. Use of an aqueous emulsion according to any preceding claim as surface coating for providing adhesions between a polypropylene based material, such as a film, fiber, or molded PP, TPO or TPV component and a polar material such as a coating layer, metal surface, metallized film, wire, fiber, fillers, flock etc. * SS * I * ** a... * S *e'.

S..... * S S.. * S. c. S S. S * S S * S.