Patent Description:
Filled polypropylene compounds based on heterophasic polyolefin compositions are widely used in the automotive industry to obtain injection molded parts having aesthetical interior applications.

Glass fibers reinforced heterophasic polyolefin compositions known in the art are generally characterized by a good balance of stiffness and impact, soft touch haptic and good scratch resistance.

The International patent application <CIT> discloses a composition suitable for foamed injection molded articles having good free-flowing properties and uniform cell characteristics, the composition comprising <NUM>-<NUM>% by weight of a first propylene based component having a flexural modulus higher than <NUM> MPA, <NUM>-<NUM>% by weight of an heterophasic propylene polymer comprising <NUM>-<NUM>% by weight of crystalline polypropylene and <NUM>-<NUM>% by weight of an ethylene-propylene copolymer containing <NUM>-<NUM>% by weight of ethylene and <NUM>-<NUM>% by weight of glass fibers.

The patent application <CIT> discloses easily processable polyolefin compositions having good impact/stiffness balance and low density, the composition having a melt flow rate from <NUM> to <NUM>/<NUM>. and comprising <NUM>-<NUM>% by weight of a polyolefin composition comprising <NUM>-<NUM>% by weight of a propylene copolymer containing <NUM>-<NUM>% of comonomer and <NUM>-<NUM>% by weight of a copolymer of an ethylene copolymer containing <NUM>-<NUM>% by weight of ethylene, <NUM>-<NUM>% by weight of a glass fiber filler, <NUM>-<NUM>% by weight of a compatibilizer and <NUM>-<NUM>% by weight of a further polymer component.

<CIT> discloses a composition comprising two HECOs and an inorganic filler for automotive applications, wherein the filler is not glass fibers.

<CIT> discloses a fiber reinforced material comprising a HECO, a plastomer, glass fibers and a compatibilizer suitable for producing automotive interior trim articles.

In this context, it is still desirable to make available glass fibers filled polyolefin compositions retaining or improving the properties of the prior art blends, namely the balance of mechanical properties, the good flowability, the soft touch haptic, the low shrinkage and the high scratch resistance.

The present disclosure provides a filled polymer composition comprising:.

wherein the amounts of (a), (b) and (c) are based on the total weight of (a)+(b)+(c).

The polyolefin composition of the present disclosure shows a good balance of mechanical properties, in particular of impact and strength, in combination with a high melt flow rate.

The polyolefin composition of the instant disclosure are also endowed with low shrinkage and adequate scratch resistance.

While multiple embodiments are disclosed, still other embodiments will become apparent to those skilled in the art from the following detailed description. As will be apparent, certain embodiments, as disclosed herein, are capable of modifications in various obvious aspects, all without departing from the spirit and scope of the claims as presented herein. Accordingly, the following detailed description is to be regarded as illustrative in nature and not restrictive.

In the context of the present disclosure;.

The total weight of a polymer or of a polymer composition sums up to <NUM>%, unless otherwise specified.

In one embodiment, the filled polyolefin composition comprises or consists of:.

wherein the amount of (a), (b) and (c) are based on the total weight of (a)+(b)+(c).

The heterophasic polypropylene HECO1 comprises a propylene copolymer (A1) preferably comprising <NUM>-<NUM>% by weight, preferably <NUM>-<NUM>% by weight, more preferably <NUM>-<NUM>% by weight, based on the weight of component (A1), of units deriving from hexene-<NUM>.

In a preferred embodiment, the propylene copolymer (A1) comprises hexene-<NUM> as sole comonomer.

In an alternative embodiment, the propylene copolymer (A1) comprises hexene-<NUM> and <NUM>-<NUM>% by weight, based on the weight of component (A1), of at least one further alpha-olefin selected from the group consisting of ethylene, butene-<NUM>, <NUM>-methyl-<NUM>-pentene, octene-<NUM> and combinations thereof.

Preferably, the propylene copolymer (A1) has melt flow rate MFR(A1) measured according to ISO <NUM>, <NUM> ranging from <NUM> to <NUM>/<NUM>, more preferably from <NUM> to <NUM>/<NUM>.

In some embodiments, the propylene copolymer (A1) comprises an amount of fraction soluble in xylene at <NUM> XS(A1) lower than <NUM>% by weight, based on the weight of component (A1), preferably lower than <NUM>% by weight, in preferred embodiments XS(A1) is comprised in the range <NUM>-<NUM>% by weight, preferably <NUM>-<NUM>% by weight, more preferably <NUM>-<NUM>% by weight.

Preferably, the propylene copolymer (B1) comprises an amount of fraction soluble in xylene at <NUM> XS(B1) equal to or greater than <NUM>% by weight, based on the total weight of component (B1), preferably equal to or greater than <NUM>% by weight, more preferably equal to or greater than <NUM>% by weight.

In one embodiment, the upper limit of the amount of the fraction of component (B1) soluble in xylene at <NUM> XS(B1) is <NUM>% by weight, based on the total weight of component (B1), for each lower limit.

In some embodiments, the component (B1) comprises a first copolymer (B1. <NUM>) and a second copolymer (B1. <NUM>) of propylene with at least one alpha-olefin of formula CH<NUM>=CHR, and optionally a diene, where R is H or a linear or branched C2-C8 alkyl, provided that the total amount of alpha-olefin comprised in the propylene copolymer (B1) is <NUM>-<NUM>% by weight, based on the total weight of component (B1).

In one embodiment, the component (B1) comprises:.

wherein the amounts of (B1. <NUM>) and (B1. <NUM>) are based on the total weight of (B1. <NUM>)+(B1.

In one embodiment, the upper limit of XS(B1. <NUM>) and/or of XS(B1. <NUM>) is <NUM>% by weight for each lower limit, XS(B1. <NUM>) and XS(B1. <NUM>) being based on the weight of component (B1. <NUM>) and (B1. <NUM>) respectively.

In some embodiments, the first heterophasic polypropylene HECO1 comprises an amount of fraction soluble in xylene at <NUM> XS(<NUM>) equal to or greater than <NUM>% by weight, based on the total weight of (A1)+(B1), preferably ranging from <NUM> to <NUM>% by weight, more preferably from <NUM> to <NUM>% by weight.

Preferably, the first heterophasic polypropylene HECO1 has melt flow rate MFR(<NUM>), measured according to ISO <NUM>, <NUM>, <NUM>, ranging from <NUM> to <NUM>/<NUM>. , more preferably from <NUM> to <NUM>/<NUM>. , still more preferably from <NUM> to <NUM>/<NUM>.

In a preferred embodiment, the melt flow rate MFR(<NUM>) of the first heterophasic polypropylene HECO1 measured according to ISO <NUM>, <NUM>, <NUM> ranging from <NUM> to <NUM>/<NUM>. , preferably from <NUM> to <NUM>/<NUM>. , more preferably from <NUM> to <NUM>/<NUM>. is obtained by visbreaking the heterophasic polypropylene obtained from the polymerization reaction.

The visbreaking is carried out by methods known in the art, eg. by mixing the polyolefin with an organic peroxide in the molten state.

Preferably, the intrinsic viscosity of the fraction soluble in xylene XSIV(<NUM>) of the first heterophasic polypropylene HECO1 is equal to or lower than <NUM> dl/g.

Preferably, the heterophasic polypropylene HECO1 comprises <NUM>-<NUM>% by weight, preferably <NUM>-<NUM>% by weight of component (A1) and <NUM>-<NUM>% by weight, preferably <NUM>-<NUM>% by weight of component (B1), wherein the amounts of (A1) and (B1) are based on the total weight of (A1)+(B1).

Preferably, the at least one alpha-olefin comprised in component (B1) is selected from the group consisting of ethylene, butene-<NUM>, hexene-<NUM>, <NUM>-methy-pentene-<NUM>, octene-<NUM> and combinations thereof, ethylene being the most preferred.

Optionally, the propylene copolymer (B1) comprises recurring units derived from a diene, the diene being preferably independently selected from the group consisting of butadiene, <NUM>,<NUM>-hexadiene, <NUM>,<NUM>-hexadiene, ethylidene-<NUM>-norbonene and combinations thereof.

In some embodiments, the total amount of recurring units deriving from a diene ranges from <NUM> to <NUM>% by weight, based on the weight of component (B1).

In a particularly preferred embodiment, the heterophasic polypropylene HECO1 comprises:.

wherein the heterophasic polypropylene HECO1:.

wherein the amounts of (A1), (B1) and XS(<NUM>) are based on the total weight of (A1)+(B1) and wherein (A1) and (B1) are as described above.

The heterophasic polypropylene HECO1 preferably has at least one of the following mechanical properties:.

In a preferred embodiment, the heterophasic polypropylene HECO1 has flexural modulus, Shore A and Shore D values comprised in the ranges indicated above.

The heterophasic polypropylene HECO1 is preferably prepared by a sequential polymerization process comprising at least two stages, wherein the second and each subsequent polymerization stage is carried out in the presence of the polymer produced and the catalyst present in the immediately preceding polymerization stage.

The polymerization processes is carried out in the presence of a catalyst selected from metallocene compounds, highly stereospecific Ziegler-Natta catalyst systems and combinations thereof.

In a preferred embodiment, the polymerization processes is carried out in the presence of a highly stereospecific Ziegler-Natta catalyst system comprising:.

In some preferred embodiments, the solid catalyst component (<NUM>) comprises a titanium compound of formula Ti(OR)nXy_n, wherein n is comprised between <NUM> and y; y is the valence of titanium; X is halogen and R is a hydrocarbon group having <NUM>-<NUM> carbon atoms or a -COR group. Among them, particularly preferred are titanium compounds having at least one Ti-halogen bond such as titanium tetrahalides or titanium halogenalcoholates. Preferred specific titanium compounds are TiCl<NUM>, TiCl<NUM>, Ti(OBu)<NUM>, Ti(OBu)Cl<NUM>, Ti(OBu)<NUM>Cl<NUM>, Ti(OBu)<NUM>Cl. TiCl<NUM> is particularly preferred.

In one embodiment, the solid catalyst component (<NUM>) comprises a titanium compound in an amount securing the presence of from <NUM> to <NUM>% by weight of Ti with respect to the total weight of the solid catalyst component (<NUM>).

The solid catalyst component (<NUM>) comprises at least one stereoregulating internal electron donor compound selected from mono or bidentate organic Lewis bases, preferably selected from esters, ketones, amines, amides, carbamates, carbonates, ethers, nitriles, alkoxysilanes and combinations thereof.

Particularly preferred are the electron donors belonging to aliphatic or aromatic mono- or dicarboxylic acid esters and diethers.

Among alkyl and aryl esters of optionally substituted aromatic polycarboxylic acids, preferred donors are the esters of phthalic acids such as those described in <CIT> and <CIT>.

In some embodiments, the internal electron donor is selected from the group consisting of mono- or di-substituted phthalates, wherein the substituents are independently selected among linear or branched C<NUM>-<NUM> alkyl, C<NUM>-<NUM> cycloalkyl and aryl radicals.

In some preferred embodiments, the internal electron donor is selected among di-isobutyl phthalate, di-n-butyl phthalate, di-n-octyl phthalate, diphenyl phthalate, benzylbutyl phthalate and combinations thereof.

In one embodiment, the internal electron donor is di-isobutyl phthalate.

Esters of aliphatic acids can be selected from malonic acids such as those described in <CIT>, <CIT>, <CIT>, glutaric acids such as those disclosed in <CIT>, and succinic acids such as those disclosed <CIT>.

Particular type of diesters are those deriving from esterification of aliphatic or aromatic diols such as those described in <CIT> and <CIT>.

In some embodiments, the internal electron donor is selected from <NUM>,<NUM>-diethers of formula
<CHM>
wherein RI and RII are independently selected from C<NUM>-<NUM> alkyl, C<NUM>-<NUM> ccycloalkyl and C<NUM>-<NUM> aryl radicals, RIII and RIV are independently selected from C<NUM>-<NUM> alkyl radicals; or the carbon atom in position <NUM> of the <NUM>,<NUM>-diether belongs to a cyclic or polycyclic structure made up of from <NUM> to <NUM> carbon atoms, or of <NUM>-n or <NUM>-n' carbon atoms, and respectively n nitrogen atoms and n' heteroatoms selected from the group consisting of N, O, S and Si, where n is <NUM> or <NUM> and n' is <NUM>, <NUM>, or <NUM>, said structure containing two or three unsaturations (cyclopolyenic structures), and optionally being condensed with other cyclic structures, or substituted with one or more substituents selected from the group consisting of linear or branched alkyl radicals; cycloalkyl, aryl, aralkyl, alkaryl radicals and halogens, or being condensed with other cyclic structures and substituted with one or more of the above mentioned substituents that can also be bonded to the condensed cyclic structures, wherein one or more of the above mentioned alkyl, cycloalkyl, aryl, aralkyl, or alkaryl radicals and the condensed cyclic structures optionally contain one or more heteroatom(s) as substitutes for carbon and/or hydrogen atoms. Ethers of this type are described in <CIT>, <CIT> and <CIT>.

When <NUM>,<NUM>-diethers described above are used, the external electron donor (<NUM>) can be absent.

In some cases, specific mixtures of internal donors, in particular between aliphatic or aromatic mono or dicarboxylic acid esters and <NUM>,<NUM>-diethers as disclosed in <CIT> and <CIT> can be used as internal donor.

Preferred magnesium halide support is magnesium dihalide.

In one embodiment, the amount of internal electron donor which remains fixed on the solid catalyst component (<NUM>) is <NUM> to <NUM>% by moles, with respect to the magnesium dihalide.

Preferred methods for the preparation of the solid catalyst components start from Mg dihalide precursors that upon reaction with titanium chlorides converts the precursor into the Mg dihalide support. The reaction is preferably carried out in the presence of the steroregulating internal donor.

In a preferred embodiment the magnesium dihalide precursor is a Lewis adduct of formula MgCl<NUM>•nR1OH, where n is a number between <NUM> and <NUM>, and R1 is a hydrocarbon radical having <NUM>-<NUM> carbon atoms. Preferably, n ranges from <NUM> to <NUM> and more preferably from <NUM> to <NUM>.

The adduct can be suitably prepared by mixing alcohol and magnesium chloride, operating under stirring conditions at the melting temperature of the adduct (<NUM>-<NUM>).

Then, the adduct is mixed with an inert hydrocarbon immiscible with the adduct thereby creating an emulsion which is quickly quenched causing the solidification of the adduct in the form of spherical particles.

The so obtained adduct can be directly reacted with the Ti compound or it can be previously subjected to thermal controlled dealcoholation (<NUM>-<NUM>) so as to obtain an adduct in which the number of moles of alcohol is generally lower than <NUM> preferably between <NUM> and <NUM>.

This controlled dealcoholation step may carried out in order to increase the morphological stability of the catalyst during polymerization and/or to increase the catalyst porosity as described in <CIT>.

The reaction with the Ti compound can be carried out by suspending the optionally dealcoholated adduct in cold TiCl<NUM> (generally at <NUM>). The mixture is heated up to <NUM>-<NUM> and kept at this temperature for <NUM>,<NUM>-<NUM> hours. The treatment with TiCl<NUM> can be carried out one or more times. The stereoregulating internal donor can be added during the treatment with TiCl<NUM>. The treatment with the internal donor can be repeated one or more times.

The preparation of catalyst components according to this general method is described for example in European Patent Applications <CIT>, <CIT>, <CIT> and as already mentioned, in <CIT>.

In one embodiment, the catalyst component (<NUM>) is in the form of spherical particles having an average diameter ranging from <NUM> to <NUM>, a surface area ranging from <NUM> to <NUM><NUM>/g, preferably from <NUM> to <NUM><NUM>/g and porosity greater that <NUM>/g, preferably of from <NUM> to <NUM>/g, wherein the surface area and the porosity are measured by BET.

In some preferred embodiments, the catalyst system comprises an Al-containing cocatalyst (<NUM>) selected from Al-trialkyls, preferably selected from the group consisting of Altryethyl, Al-triisobutyl and Al-tri-n-butyl.

In one embodiment, the Al/Ti weight ratio in the catalyst system is from <NUM> to <NUM>, preferably from <NUM> to <NUM>.

In a preferred embodiment, the catalyst system comprises a further electron donor compound (<NUM>) (external electron donor) selected among silicon compounds, ethers, esters, amines, heterocyclic compounds, particularly <NUM>,<NUM>,<NUM>,<NUM>-tetramethylpiperidine, and ketones.

Preferably, the external donor is selected among silicon compounds of formula (R2)a(R3)bSi(OR4)c, where a and b are integers from <NUM> to <NUM>, c is an integer from <NUM> to <NUM> and the sum (a+b+c) is <NUM>; R2, R3, and R4, are alkyl, cycloalkyl or aryl radicals with <NUM>-<NUM> carbon atoms, optionally containing heteroatoms. Particularly preferred are the silicon compounds in which a is <NUM>, b is <NUM>, c is <NUM>, at least one of R2 and R3 is selected from branched alkyl, cycloalkyl or aryl groups with <NUM>-<NUM> carbon atoms, optionally containing heteroatoms, and R4 is a C1-C10 alkyl group, in particular methyl.

Examples of such preferred silicon compounds are selected among methylcyclohexyldimethoxysilane (C-donor), diphenyldimethoxysilane, methyl-t-butyldimethoxysilane, dicyclopentyldimethoxysilane (D-donor), diisopropyldimethoxysilane, (<NUM>-ethylpiperidinyl)t-butyldimethoxysilane, (<NUM>-ethylpiperidinyl)thexyldimethoxysilane, (<NUM>,<NUM>,<NUM>-trifluoro-n-propyl)(<NUM>-ethylpiperidinyl)dimethoxysilane, methyl(<NUM>,<NUM>,<NUM>-trifluoro-n-propyl)dimethoxysilane and combinations thereof.

The silicon compounds in which a is <NUM>, c is <NUM>, R3 is a branched alkyl or cycloalkyl group, optionally containing heteroatoms, and R4 is methyl are also preferred. Examples of such silicon compounds are cyclohexyltrimethoxysilane, t-butyltrimethoxysilane and hexyltrimethoxysilane.

Even if several combinations of the components of the catalyst system allow to obtain the polyolefin compositions of the present disclosure, a particularly suitable catalyst system comprises di-isobutyl phthalate as internal electron donor and dicyclopentyl dimethoxy silane (D-donor) as external electron donor.

In one embodiment, the catalyst system is pre-contacted with small quantities of olefin (prepolymerization), maintaining the catalyst in suspension in a hydrocarbon solvent, and polymerizing at temperatures from <NUM>° to <NUM> producing a quantity of polymer from about <NUM> to about <NUM> times the weight of the catalyst system.

In an alternative embodiment, the prepolymerization is carried out in liquid monomer, producing a quantity of polymer <NUM> times the weight of the catalyst system.

Sequential polymerization processes for preparing the heterophasic polypropylene HECO1 are described in <CIT> and <CIT>, whose content is incorporated in this patent application for reference purposes.

The components (A1) and (B1) can be produced in any one of the polymerization stages.

In one embodiment, the process to prepare the heterophasic polypropylene HECO1 comprises at least two polymerization stages carried out in the presence of a highly stereospecific Ziegler-Natta catalyst system, wherein:.

In one embodiment, the second copolymerization stage (b) comprises a copolymerization stage (b1) and a copolymerization stage (b2), wherein the appropriate comonomers are polymerized to form the propylene copolymer (B1. <NUM>) in the stage (b1) and the appropriate comonomers are polymerized to form the propylene copolymer (B1. <NUM>) in the stage (b2).

The polymerization, which can be continuous or batch, can be carried out according to known cascade techniques operating either in mixed liquid phase/gas phase or, preferably, totally in gas phase.

The liquid-phase polymerization can be either in slurry, solution or bulk (liquid monomer). This latter technology is the most preferred and can be carried out in various types of reactors such as continuous stirred tank reactors, loop reactors or plug-flow reactors.

The gas-phase polymerization stages can be carried out in gas-phase reactors, such as fluidized or stirred, fixed bed reactors.

In one embodiment, the copolymerization stage (a) is carried out in liquid phase using liquid propylene as diluent and the copolymerization stage (b), or the copolymerization stages (b1) and (b2), are carried out in the gas phase.

In a preferred embodiment, also the copolymerization stage (a) is carried out in the gas phase.

In one embodiment, the reaction temperatures of the polymerization stages (a) and (b) are independently selected in the range from <NUM>° to <NUM>.

In one embodiment, the polymerization pressure of the copolymerization stage (a) carried out in liquid phase is from <NUM> to <NUM> MPa.

In one embodiment, the polymerization pressure of the copolymerization stages (a), and (b) carried out in gas-phase is independently selected in the range from <NUM> to <NUM> MPa.

The residence time of each polymerization stage depends upon the desired ratio of component (A1) to component (B1). In one embodiment, the residence time in each polymerization stage ranges from <NUM> minutes to <NUM> hours.

In a sequential polymerization process, the amounts of components (A1) and (B1) correspond to the split between the polymerization reactors.

The molecular weight of the propylene copolymers obtained in each polymerization stage is regulated using chain transfer agents, such as hydrogen or ZnEt<NUM>.

In one embodiment, the process to prepare the heterophasic polypropylene HECO1 comprises a step (c) of melt mixing the polymer granules with at least one organic peroxide and/or at least one additive (C) selected from the group consisting of antistatic agents, anti-oxidants, anti-acids, melt stabilizers and combinations thereof.

Preferably, the step (c) preferably comprises melt mixing the polymer granules with up to and including <NUM>% by weight, preferably from <NUM> to <NUM>% by weight, more preferably from <NUM> to <NUM>% by weight, of the at least one additive (C) and/or with up to and including <NUM>% by weight, preferably up to and including <NUM>% by weight, of an organic peroxide, wherein:.

Thus, in one embodiment, the heterophasic polypropylene HECO1 comprises up to and including <NUM>% by weight, preferably from <NUM> to <NUM>% by weight, more preferably from <NUM> to <NUM>% by weight, of the at least one additive (C) selected from the group consisting of antistatic agents, anti-oxidants, anti-acids, melt stabilizers and combinations thereof, of the type used in the polyolefin field, and up to and including <NUM>% by weigh, preferably up to and including <NUM>% by weight of an organic peroxide, wherein the amount of the additive and of the organic peroxide is based on the weight of the polymer comprising the additive (C) and/or the organic peroxide.

In one embodiment, the lower limit of the amount of the organic peroxide is of <NUM> % by weight, based on the weight of the polymer comprising the organic peroxide and optionally the additive (C), for each lower limit.

In one embodiment, the heterophasic polypropylene HECO1 consists of component (A1) and (B1), the at least one additive (C) and the organic peroxide, preferably in the amounts as described above.

The heterophasic polypropylene HECO2 is different from the heterophasic polypropylene HECO2 and has melt flow rate MFR(<NUM>) measured according to ISO <NUM>, <NUM>, <NUM> equal to or greater than <NUM>/<NUM>, preferably ranging from <NUM> to <NUM>/<NUM>. , still more preferably from <NUM> to <NUM>/<NUM>.

In one preferred embodiment, the propylene polymer (A2) comprises up to and including <NUM>% by weight of units deriving from ethylene as the sole comonomer.

Preferably, the at least one alpha-olefin comprised in component (B2) is selected from the group consisting of ethylene, butene-<NUM>, hexene-<NUM>, <NUM>-methy-pentene-<NUM>, octene-<NUM> and combinations thereof, ethylene being the most preferred.

Optionally, the propylene copolymer (B2) comprises recurring units derived from a diene, the diene being preferably independently selected from the group consisting of butadiene, <NUM>,<NUM>-hexadiene, <NUM>,<NUM>-hexadiene, ethylidene-<NUM>-norbonene and combinations thereof.

In some embodiments, the total amount of recurring units deriving from a diene ranges from <NUM> to <NUM>% by weight, based on the weight of component (B2).

In a preferred embodiment, the heterophasic polypropylene HECO2 has at least one of the following mechanical properties, measured on <NUM>-thick injection molded specimens obtained according to the method ISO <NUM>-<NUM>:<NUM>:.

In one preferred embodiment, the heterophasic polypropylene HECO2 is endowed with all the properties above.

The heterophasic polypropylene HECO2 is preferably prepared by a sequential polymerization process comprising at least two stages, wherein the second and each subsequent polymerization stage is carried out in the presence of the polymer produced and the catalyst present in the immediately preceding polymerization stage.

The catalyst systems and the polymerization process described above for producing the heterophasic polypropylene HECO1 are also suitable for producing the heterophasic polypropylene HECO2.

In one embodiment, the heterophasic polypropylene HECO2 comprises up to and including <NUM>% by weight, preferably from <NUM> to <NUM>% by weight, more preferably from <NUM> to <NUM>% by weight, based on the weight of the heterophasic polypropylene HECO2 comprising the additive, of the at least one additive (C) selected from the group consisting of antistatic agents, anti-oxidants, anti-acids, melt stabilizers and combinations thereof, of the type used in the polyolefin field.

The polyolefin composition of the present disclosure comprises glass fibers (b) preferably having diameter of up to and including <NUM>, more preferably ranging from <NUM> to <NUM>, still more preferably from <NUM> to <NUM> and length equal to or lower than <NUM>, preferably ranging from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, more preferably from <NUM> to <NUM>.

E-glass fibers are particularly preferred and generally available as sized fibers, i.e. coated with a coupling agent which increases the compatibility of the fibers with the polymer into which the fibers are dispersed.

A compatibilizer (c) is optionally but preferably present in the filled polyolefin composition, and it is preferably a modified olefin polymer functionalized with a polar compound.

The functionalizing polar compound includes, but is not limited to, acid anhydrides, carboxylic acids, carboxylic acid derivatives, primary and secondary amines, hydroxyl compounds, oxazoline, epoxides, ionic compounds and combinations thereof. Specific examples of functionalizing polar compounds are unsaturated cyclic anhydrides, their aliphatic diesters, and diacid derivatives.

Preferably, the compatibilizer (c) is a polyolefin selected from polyethylenes, polypropylenes and mixtures thereof, functionalized with a compound selected from the group consisting of maleic anhydride, C1-C10 linear or branched dialkyl maleates, C1-C10 linear or branched dialkyl fumarates, itaconic anhydride, C1-C10 linear or branched itaconic acid, dialkyl esters, maleic acid, fumaric acid, itaconic acid and mixtures thereof.

In a particularly preferred embodiment, the compatibilizer (c) is a polyethylene and/or a polypropylene grafted with maleic anhydride (MAH-g-PP and/or MAH-g-PE).

Modified olefin polymers functionalized with a polar compound are known in the art and can be produced by functionalization processes carried out in solution, in the solid state or preferably in the molten state, eg. by reactive extrusion of the polymer in the presence of the grafting compound and of a free radical initiator. Functionalization of polypropylene and/or polyethylene with maleic anhydride is described for instance in <CIT>.

Examples of modified polyolefins suitable for use as compatibilizer are the commercial products Amplify™ TY by The Dow Chemical Company, Exxelor™ by ExxonMobil Chemical Company, Scona® TPPP by Byk (Altana Group), Bondyram® by Polyram Group and Polybond® by Chemtura and combinations thereof.

In one further embodiment, the filled polyolefin composition optionally comprises <NUM>-<NUM>% by weight, preferably <NUM>-<NUM>% by weight, more preferably <NUM>-<NUM>% by weight, of at least one additive (d) selected from the group consisting of fillers, pigments, nucleating agents, extension oils, flame retardants (e. aluminum trihydrate), UV resistants (e. titanium dioxide), UV stabilizers, lubricants (e. , oleamide), antiblocking agents, waxes, and combinations thereof, the amount of the additive (d) being based on the total weight of (a)+(b)+(c)+(d).

In one embodiment, the filled polyolefin composition further comprises at least one polymer (e) selected from the group consisting of:.

The styrene block copolymer is preferably selected from the group consisting of: polystyrene-polybutadiene-polystyrene (SBS), polystyrene-poly(ethylene-butylene)-polystyrene (SEBS), polystyrene-poly(ethylene-propylene)-polystyrene (SEPS), polystyrene-polyisoprene-polystyrene (SIS), polystyrene-poly(isoprene-butadiene)-polystyrene (SIBS) and mixtures thereof. More preferably the styrene block copolymer is a polystyrene-poly(ethylene-butylene)-polystyrene (SEBS).

Styrene or alpha-methylstyrene block copolymers are generally prepared by ionic polymerization of the relevant monomers and are commercially available under the tradename of Kraton™ marketed by Kraton Polymers.

The ethylene copolymer preferably comprises at least <NUM>% by weight, more preferably from <NUM> to <NUM>% by weight based on the weight of the polymer (e), of units deriving from the alpha-olefin. The alpha-olefin is preferably selected from butene-<NUM>, hexene-<NUM>, octene-<NUM> and combinations thereof.

Ethylene copolymers are commercially available under the tradename of Engage, eg. Engage™ <NUM> or Engage™ <NUM>, marketed by Dow® and are prepared using known polymerization processes, such as solution polymerization processes carried out in the presence of a metallocene-based catalyst system.

When present, the amount of the further polymer (e) preferably ranges from <NUM> to <NUM>% by weight, preferably from <NUM> to <NUM>% by weight, more preferably from <NUM> to <NUM>% by weight, the amount of the further polymer (e) being based on the total weight of (a)+(b)+(c)+(d)+(e).

The filled polyolefin composition is prepared by metering the components to an extruder, preferably to a twin screw extruder, operated at a temperature comprised in the range from <NUM>° to <NUM>.

The filled polyolefin composition of the instant disclosure has good flowability in the molten state having a melt flow rate MFR(tot), measured according to ISO <NUM>, <NUM>, <NUM>, equal to or greater than <NUM>/<NUM>. , preferably ranging from <NUM> to <NUM>/<NUM>. , more preferably from <NUM> to <NUM>/<NUM>.

Preferably, the filled polyolefin composition of the present disclosure is endowed with at least one of the following properties:.

The flexural modulus, Vicat A softening temperature and Charpy impact strength were determined on injection molded multipurpose bars obtained according to EN ISO <NUM> (Type A1); the shrinkage <NUM>/RT and the scratch resistance were measured according to the methods described in the experimental section on dedicated specimens.

In one preferred embodiment, the filled polyolefin composition is endowed with all the properties above.

The balance of mechanical properties of the filled polyolefin composition renders the filled polyolefin composition suitable for use in producing molded articles, preferably injection molded articles.

A further object of the present disclosure is therefore a process to produce a molded article comprising the steps of:.

The process can be carried out using conventional molding apparatuses, in particular an injection molding apparatus.

A further object of the present disclosure is an article, preferably an injection molded article, comprising or consisting of the filled polyolefin composition of the present disclosure, wherein the injection molded article is preferably selected from vehicle interior trims, vehicle exterior trims and under the hood articles.

It should be noted that the features describing the filled polyolefin composition of the present disclosure are not inextricably linked to each other. As a consequence, a certain level of preference of one feature does not necessarily involve the same level of preference of the remaining features of the same or different components. It is intended in the present disclosure that any preferred range of features of components from (a) to (e) from which the filled polyolefin composition is obtained can be combined independently from the level of preference.

The following examples are illustrative only, and are not intended to limit the scope of the disclosure in any manner whatsoever.

The following methods are used to determine the properties indicated in the description and claims.

Melt Flow Rate: Determined according to the method ISO <NUM> (<NUM>, <NUM>).

Solubility in xylene at <NUM>: <NUM> of polymer sample and <NUM> of xylene are introduced in a glass flask equipped with a refrigerator and a magnetic stirrer. The temperature is raised in <NUM> minutes up to <NUM>. The obtained clear solution is kept under reflux and stirring for further <NUM> minutes. The solution is cooled in two stages. In the first stage, the temperature is lowered to <NUM> in air for <NUM> to <NUM> minute under stirring. In the second stage, the flask is transferred to a thermostatically controlled water bath at <NUM> for <NUM> minutes. The temperature is lowered to <NUM> without stirring during the first <NUM> minutes and maintained at <NUM> with stirring for the last <NUM> minutes. The formed solid is filtered on quick filtering paper (eg. Whatman filtering paper grade <NUM> or <NUM>). <NUM> of the filtered solution (S1) is poured in a previously weighed aluminum container, which is heated to <NUM> on a heating plate under nitrogen flow, to remove the solvent by evaporation. The container is then kept on an oven at <NUM> under vacuum until constant weight is reached. The amount of polymer soluble in xylene at <NUM> is then calculated. XS(tot) and XSA values are experimentally determined. The fraction of component (B) soluble in xylene at <NUM> (XSB) can be calculated from the formula: <MAT> wherein W(A) and W(B) are the relative amounts of components (A) and (B), respectively, and W(A)+ W(B)=<NUM>.

Intrinsic viscosity of the xylene soluble fraction: to calculate the value of the intrinsic viscosity IV, the flow time of a polymer solution is compared with the flow time of the solvent (THN). A glass capillary viscometer of Ubbelohde type is used. The oven temperature is adjusted to <NUM>. Before starting the measurement of the solvent flow time t0 the temperature must be stable (<NUM>° ± <NUM>). Sample meniscus detection for the viscometer is performed by a photoelectric device. Sample preparation: <NUM> of the filtered solution (S1) is poured in a beaker and <NUM> of acetone are added under vigorous stirring. Precipitation of insoluble fraction must be complete as evidenced by a clear solid-solution separation. The suspension is filtered on a weighed metallic screen (<NUM> mesh), the beaker is rinsed and the precipitate is washed with acetone so that the o-xylene is completely removed. The precipitate is dried in a vacuum oven at <NUM> until a constant weight is reached. <NUM> of precipitate are weighted and dissolved in <NUM> of tetrahydronaphthalene (THN) at a temperature of <NUM>. The efflux time t of the sample solution is measured and converted into a value of intrinsic viscosity [η] using Huggins' equation (<NPL>) and the following data:.

One single polymer solution is used to determine [η].

Comonomer content: determined by IR using Fourier Transform Infrared Spectrometer (FTIR). The spectrum of a pressed film of the polymer is recorded in absorbance vs. wavenumbers (cm-<NUM>). The following measurements are used to calculate ethylene and hexene-<NUM> content:.

The method is calibrated by using polymer standards based on <NUM>C NMR analyses. Sample preparation: Using a hydraulic press, a thick sheet is obtained by pressing about <NUM> of sample between two aluminum foils. Pressing temperature is <NUM>±<NUM> (<NUM>°F) and about <NUM>/cm<NUM> pressure for about one minute (minimum two pressing operations for each specimen). A small portion is cut from this sheet to mold a film. Recommended film thickness ranges between <NUM>-<NUM>.

HDT A: measured according to the method ISO <NUM>/A (<NUM> MPa).

Flexural modulus: Determined according to the method ISO <NUM>:<NUM>.

Tensile strength and elongation: Determined according to the method ISO <NUM>-<NUM>,-<NUM>.

Vicat A softening temperature: Determined according to the method ISO <NUM> (A/50N).

Charpy impact strength test at <NUM>: measured according to ISO <NUM>/1eA <NUM>.

Preparation of compression molded plaques: obtained according to ISO <NUM>-<NUM>:<NUM>.

Shore A and D on compression molded plaques: Determined according to the method ISO <NUM> (<NUM> sec).

Thermal shrinkage: a plaque of <NUM> x <NUM> x <NUM> is molded in an injection molding machine Krauss Maffei KM250/1000C2 (<NUM> tons of claiming force) under the following injection molding conditions:.

The plaque is stored under normal conditions and measured with a callipers <NUM> after molding. The shrinkage is calculated from the following formulas: <MAT> <MAT> wherein.

Scratch resistance: measured according to the test specification WV PV <NUM> (<NUM>-<NUM>) on sample, cut out of out of a DIN A5 dimension grained with K85 type grain injection molded, using a loading weight of 10N.

The component (a) of the filled polyolefin composition is prepared by a polymerization process carried out in two gas phase reactors connected in series and equipped with devices to transfer the product from the first to the second reactor. A Ziegler-Natta catalyst system is used comprising:.

The solid catalyst component is contacted with TEAL and DCPMS in a pre-contacting vessel, with a weight ratio of TEAL to the solid catalyst component of <NUM>÷<NUM>. The weight ratio TEAL/DCPMS is <NUM>.

The catalyst system is then subjected to pre-polymerization by maintaining it in suspension in liquid propylene at <NUM> for about <NUM>-<NUM> minutes before introducing it into the first polymerization reactor.

Propylene copolymer (A1) is produced into the first gas phase reactor by feeding in a continuous and constant flow the pre-polymerized catalyst system, hydrogen (used as molecular weight regulator), propylene and hexene-<NUM>, all in gaseous phase.

The propylene copolymer (A1) coming from the first reactor is discharged in a continuous flow and, after having been purged of unreacted monomers, is introduced, in a continuous flow, into the second gas phase reactor, together with quantitatively constant flows of propylene, ethylene and hydrogen, all in the gas state. In the second reactor the propylene copolymer (B1) is produced.

The polymerization conditions, molar ratio of the reactants and composition of the copolymer obtained are shown in Table <NUM>.

The polymer particles exiting the second reactor are subjected to a steam treatment to remove the unreacted monomers and volatile compounds, and then dried.

The heterophasic polypropylene HECO1 was prepared by mixing the polymer particles exiting the degassing section of the reactor with the additives (C) and an organic peroxide in the amounts indicated in Table <NUM>, in a twin screw extruder Berstorff ZE <NUM> (length/diameter ratio of screws: <NUM>) and extruded under nitrogen atmosphere in the following conditions:.

Irganox® <NUM> is <NUM>,<NUM>-bis[<NUM>-[,<NUM>-bis(<NUM>,<NUM>-dimethylethyl)-<NUM>-hydroxyphenyl]-<NUM>-oxopropoxy]methyl]-<NUM>,<NUM>-propanediyl-<NUM>,<NUM>-bis(<NUM>,<NUM>-dimethylethyl)-<NUM>-hydroxybenzene-propanoate; Irgafos® <NUM> is tris(<NUM>,<NUM>-di-tert. -butylphenyl)phosphite; Peroxan HX supplied by Pergan is <NUM>,<NUM>-dimethyl-<NUM>,<NUM>-di-(tert-butylperoxy)-hexane.

The properties of the thus obtained heterophasic polypropylene HECO1 are reported in Table <NUM>.

<NUM>: an heterophasic polypropylene comprising <NUM> wt. % of a propylene-ethylene copolymer (A2. <NUM>) containing <NUM> wt. %, based on the weight of copolymer (A2. <NUM>) of units deriving from ethylene and <NUM> wt. % of a propylene-ethylene copolymer (B2. <NUM>) containing <NUM> wt. %, based on the weight of copolymer (B2. <NUM>), of units deriving from ethylene, the amounts of (A2. <NUM>) and (B2. <NUM>) being based on the total weight of (A2. <NUM>)+(B2.

<NUM> has MFR(<NUM>) of <NUM>/<NUM>. (ISO1133, <NUM>/<NUM>), flexural modulus of <NUM> MPa (ISO <NUM>:<NUM>), tensile stress at yield of <NUM> MPa (ISO <NUM>-<NUM>,-<NUM>), tensile strain at yield of <NUM>% (ISO <NUM>-<NUM>,-<NUM>), Charpy impact strength - notched at <NUM> (ISO <NUM>, 1eA) of <NUM> kJ/m<NUM> and Vicat softening temperature of <NUM> (ISO <NUM>, A50);
HECO2. <NUM>: an heterophasic polypropylene comprising <NUM> wt. % of a propylene-ethylene copolymer (A2. <NUM>) containing <NUM> wt. %, based on the weight of the copolymer (A2. <NUM>), of units deriving from ethylene and <NUM> wt. % of a propylene ethylene copolymer (B2. <NUM>) containing <NUM> wt. %, based on the weight of the copolymer (B2. <NUM>), of units deriving from ethylene, wherein the amounts of (A2. <NUM>) and (B2. <NUM>) are based on the total weight of (A2. <NUM>)+(B2.

<NUM> has MFR(<NUM>) of <NUM>/<NUM>. (ISO1133, <NUM>/<NUM>), tensile modulus of <NUM> MPa (ISO <NUM>-<NUM>,-<NUM>), tensile stress at yield of <NUM> MPa (ISO <NUM>-<NUM>,-<NUM>), tensile strain at yield of <NUM>% (ISO <NUM>-<NUM>,-<NUM>), Charpy impact strength - notched at <NUM> (ISO <NUM>, 1eA) of <NUM> kJ/m<NUM> and Vicat softening temperature of <NUM> (ISO <NUM>, A50);.

The filled polyolefin compositions having the composition indicated in table <NUM> are prepared by mixing the components in a <NUM> Werner & Pfleiderer extruder (L/D of <NUM>) operated under the following extruding conditions:.

The compositions are tested for physical and mechanical properties on multipurpose bars obtained by injection molding according to the method EN ISO <NUM> (Type A1) and the test results are reported in the same table <NUM>.

In the same table <NUM> the test results are compared with the data reported in table <NUM> of <CIT> for Ref. <NUM>. The composition of Ref. <NUM> of <CIT> comprises:.

- <NUM> wt. % of a polymer named HECO2 comprising a <NUM> wt. % of a propylene copolymer containing <NUM> wt. % of ethylene, <NUM> wt. % of a propylene/ethylene copolymer containing <NUM> wt. % of ethylene and <NUM> wt. % of a second propylene/ethylene copolymer containing <NUM> wt. % of ethylene, the polymer having MFR of <NUM>/<NUM>. (ISO1133, <NUM>/<NUM>);
- <NUM> wt. % of a polymer named HECO3 being an heterophasic polyolefin comprising <NUM> wt. % of a propylene homopolymer and <NUM> wt. % of a propylene/ethylene copolymer containing <NUM> wt. % of ethylene and having MFR of <NUM>/<NUM>. (ISO1133, <NUM>/<NUM>);
- <NUM> wt. % of a propylene homopolymer having MFR of <NUM>/<NUM>. (ISO1133, <NUM>/<NUM>);
- <NUM> wt. % of glass fibers;
- <NUM> wt. % of polypropylene grafted with maleic anhydride
- <NUM> wt. % of additive pack.

The filled polyolefin compositions having the composition indicated in table <NUM> are prepared by mixing the components in a <NUM> Werner & Pfleiderer extruder (L/D of <NUM>) extruder under the same extruding conditions used for examples E1-E2.

Claim 1:
A filled polymer composition comprising:
(a) <NUM>-<NUM>% by weight of a polyolefin blend comprising:
(i) <NUM>-<NUM>% by weight of a first heterophasic polypropylene HECO1 comprising:
(A1) <NUM>-<NUM>% by weight of a copolymer of propylene with hexene-<NUM> comprising <NUM>-<NUM>% by weight, based on the weight of (A1), of units deriving from hexene-<NUM> and having melt flow rate MFR(A1) measured according to ISO <NUM>, <NUM>, <NUM>, equal to or greater than <NUM>/<NUM>; and
(B1) <NUM>-<NUM>% by weight of a copolymer of propylene with at least one alpha-olefin of formula CH<NUM>=CHR, and optionally a diene, where R is H or a linear or branched C2-C8 alkyl, the copolymer comprising <NUM>-<NUM>% by weight, based on the weight of (B1), of monomer units deriving from the alpha-olefin,
wherein
- the heterophasic polypropylene HECO1 comprises an amount of fraction soluble in xylene (XS1) at <NUM> equal to or higher than <NUM>% by weight, and
- the amounts of (A1), (B1) and XS1 are based on the total weight of (A1)+(B1);
(ii) <NUM>-<NUM>% by weight of a second heterophasic polypropylene HECO2 having melt flow rate MFR(<NUM>), measured according to ISO <NUM>, <NUM>, <NUM>, equal to or greater than <NUM>/<NUM>. and comprising:
(A2) <NUM>-<NUM>% by weight of a propylene homopolymer or a propylene copolymer with at least one alpha-olefin of formula CH<NUM>=CHR, where R is H or a linear or branched C2-C8 alkyl, the copolymer comprising up to and including <NUM>% by weight, based on the weight of (A2), of monomer units deriving from the alpha-olefin; and
(B2) <NUM>-<NUM>% by weight of a of a copolymer of propylene with at least one alpha-olefin of formula CH<NUM>=CHR, and optionally a diene, where R is H or a linear or branched C2-C8 alkyl, the copolymer comprising <NUM>-<NUM>% by weight, based on the weight of (B2), of monomer units deriving from the alpha-olefin,
wherein the amounts of (A2) and (B2) are based on the total weight of (A2)+(B2), and
wherein the amounts of HECO1 and HECO2 are based on the total weight of HECO1+HECO2;
(b) <NUM>-<NUM>% by weight of glass fibers; and
(c) <NUM>-<NUM>% by weight of a compatibilizer,
wherein the amounts of (a), (b) and (c) are based on the total weight of (a)+(b)+(c).