FIBER REINFORCED POLYPROPYLENE COMPOSITION

Abstract

The present invention is directed to a fiber reinforced composition (C) comprising a heterophasic polypropylene composition (HECO), fibers (F) and an adhesion promoter (AP) as well as an article comprising said fiber reinforced composition (C).

Claims

1: A fiber reinforced composition (C), comprising: a) 55.0 to 95.0 wt. % of a heterophasic polypropylene composition (HECO), comprising: i) a matrix being a propylene homo- or copolymer (PP) having an amount of 1,2 erythro regio-defects of at least 0.4 mol % and a comonomer content equal or below 8.5 mol %, and ii) an elastomeric ethylene copolymer (E) being dispersed in said matrix, b) 5.0 to 45.0 wt. % of fibers (F), and c) optionally 0.1 to 5.0 wt. % of an adhesion promoter (AP), based on the overall weight of the fiber reinforced composition (C), wherein the fiber reinforced composition (C) has a melt flow rate MFR.sub.2 (230 C., 2.16 kg) determined according to ISO 1133 in the range of 1.0 to 60.0 g/10 min.

2: The fiber reinforced composition (C) according to claim 1, comprising: a) 55.0 to 94.9 wt. % of the heterophasic polypropylene composition (HECO), b) 5.0 to 45.0 wt. % of the fibers (F), and c) optionally 0.1 to 5.0 wt. % of the adhesion promoter (AP), based on the overall weight of the fiber reinforced composition (C).

3: The fiber reinforced composition (C) according to claim 1, wherein the heterophasic polypropylene composition (HECO) comprises; i) 60.0 to 95.0 wt. % of the matrix being the propylene homo- or copolymer (PP), and ii) 5.0 to 40.0 wt. % of the elastomeric ethylene copolymer (E), based on the overall weight of the heterophasic copolymer (HECO).

4: The fiber reinforced composition (C) according to claim 1, wherein the elastomeric ethylene copolymer (E) has an ethylene content in the range of 15.0 to 85.0 wt. %, based on the overall weight of the elastomeric ethylene copolymer (E).

5: The fiber reinforced composition (C) according to claim 1, wherein the heterophasic polypropylene composition (HECO) has a melting temperature Tm determined according to differential scanning calorimetry (DSC) in the range of 130 to 165 C.

6: The fiber reinforced composition (C) according to claim 1, wherein the heterophasic polypropylene composition (HECO) has an intrinsic viscosity (IV) measured according to ISO 1628/1 (at 135 C. in decalin) of the soluble fraction (SF) determined according to CRYSTEX QC in the range of 1.8 to 3.0 dl/g.

7: The fiber reinforced composition (C) according to claim 1, wherein the fibers (F) are glass fibers (GF), having; i) an average length of 2.0 to 10.0 mm, and/or ii) an average diameter of 5 to 20 m.

8: The fiber reinforced composition (C) according to claim 1, wherein the adhesion promoter (AP) is a polar modified polypropylene (PM-PP) being a propylene homo- or copolymer grafted with maleic anhydride having a melt flow rate MFR (230 C., 2.16 kg) determined according to ISO 1133 of at least 20.0 g/10 min to 400 g/10 min.

9: The fiber reinforced composition (C) according to claim 1, wherein: i) the propylene homo- or copolymer (PP) is a propylene homopolymer (hPP), and ii) the elastomeric ethylene polymer (E) is a copolymer of ethylene and propylene.

10: The fiber reinforced composition (C) according to claim 9, wherein the propylene homopolymer (hPP) has a melting temperature Tm determined according to differential scanning calorimetry (DSC) in the range of 140 to 160 C.

11: The fiber reinforced composition (C) according to claim 9, wherein the heterophasic polypropylene composition (HECO) has a comonomer content in the range of 2.2 to 8.7 mol %.

12: The fiber-reinforced composition (C) according to claim 9, wherein the heterophasic polypropylene composition (HECO) has a melt flow rate MFR.sub.2 (230 C., 2.16 kg) determined according to ISO 1133 in the range of 20.0 to 100 g/10 min.

13: The fiber-reinforced composition (C) according to claim 9, wherein the heterophasic polypropylene composition (HECO) has: a xylene cold soluble (XCS) content determined at 25 C. according ISO 16152 in the range of 5.0 to 35.0 wt. %, based on the overall weight of the heterophasic polypropylene composition (HECO).

14: The fiber-reinforced composition (C) according to claim 9, wherein the heterophasic polypropylene composition (HECO) has an ethylene content of the xylene cold soluble (XCS) fraction in the range of 20.9 to 44.7 mol %, or wherein the heterophasic polypropylene composition (HECO) has an ethylene content of a soluble fraction (SF) determined according to CRYSTEX QC in the range of 20.9 to 44.7 mol %.

15: The fiber-reinforced composition (C) according to claim 9, wherein the heterophasic polypropylene composition (HECO) has a soluble fraction (SF) determined according to CRYSTEX QC in the range of 5.0 to 35.0 wt. %, based on the overall weight of the heterophasic polypropylene composition (HECO).

16. (canceled)

17: The fiber-reinforced composition (C) according to claim 9, having a tensile modulus determined according to ISO 527-1A in the range of 3000 to 6000 MPa.

18: The fiber-reinforced composition (C) according to claim 9, having an elongation at break determined according to ISO 527-2 of more than 3.0%.

19: The fiber reinforced composition (C) according to claim 1, further comprising up to 20.0 wt. % of a low density polyethylene (LDPE) homo- or copolymer having a density determined according to ISO 1183-187 of more than 900 kg/m.sup.3 and comprising ethylene and optionally vinyl acetate.

20: The fiber reinforced composition (C) according to claim 1, wherein the propylene homo- or copolymer (PP) is obtained in the presence of a solid catalyst system (SCS) comprising a metallocene complex, having the formula (I); ##STR00006## wherein each X independently is a sigma-donor ligand, L is a divalent bridge selected from R.sub.2C, R.sub.2CCR.sub.2, R.sub.2Si, R.sub.2SiSiR.sub.2, R.sub.2Ge, wherein each R is independently a hydrogen atom or a C.sub.1-C.sub.20-hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16 of the periodic table or fluorine atoms, or optionally two R groups taken together can form a ring, each R.sup.1 are independently the same or different and are hydrogen, a linear or branched C.sub.1-C.sub.6-alkyl group, a C.sub.7-20-arylalkyl, C.sub.7-20-alkylaryl group or C.sub.6-20-aryl group or an OY group, wherein Y is a C.sub.1-10-hydrocarbyl group, and optionally two adjacent R.sup.1 groups can be part of a ring including the phenyl carbons to which they are bonded, each R.sup.2 independently are the same or can be different and are a CH.sub.2R.sup.8 group, with R.sup.8 being H or linear or branched C.sub.1-6-alkyl group, C.sub.3-8-cycloalkyl group, or C.sub.6-10-aryl group, R.sup.3 is a linear or branched C.sub.1-C.sub.6-alkyl group, C.sub.7-20-arylalkyl, C.sub.7-20-alkylaryl group or C.sub.6-C.sub.20-aryl group, R.sup.4 is a C(R.sup.9).sub.3 group, with R.sup.9 being a linear or branched C.sub.1-C.sub.6-alkyl group, R.sup.5 is hydrogen or an aliphatic C.sub.1-C.sub.20-hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16 of the periodic table; R.sup.6 is hydrogen or an aliphatic C.sub.1-C.sub.20-hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16 of the periodic table; or R.sup.5 and R.sup.6 can be taken together to form a 5 membered saturated carbon ring which is optionally substituted by n groups R.sup.10, n being from 0 to 4; each R.sup.10 is same or different and may be a C.sub.1-C.sub.20-hydrocarbyl group, or a C.sub.1-C.sub.20-hydrocarbyl group optionally containing one or more heteroatoms belonging to groups 14-16 of the periodic table; R.sup.7 is H or a linear or branched C.sub.1-C.sub.6-alkyl group or an aryl or heteroaryl group having 6 to 20 carbon atoms optionally substituted by one to three groups R.sup.11, each R.sup.11 are independently the same or different and are hydrogen, a linear or branched C.sub.1-C.sub.6-alkyl group, a C.sub.7-20-arylalkyl, C.sub.7-20-alkylaryl group or C.sub.6-20-aryl group or an OY group, wherein Y is a C.sub.1-10-hydrocarbyl group.

21: An article, comprising a fiber reinforced composition (C), the fiber reinforced composition (C) comprising: a) 55.0 to 95.0 wt. % of a heterophasic polypropylene composition (HECO), comprising i) a matrix being a propylene homo- or copolymer (PP) having an amount of 1,2 erythro regio-defects of at least 0.4 mol % and a comonomer content equal or below 8.5 mol %, and ii) an elastomeric ethylene copolymer (E) being dispersed in said matrix, b) 5.0 to 45.0 wt. % of fibers (F), and c) optionally 0.1 to 5.0 wt. % of an adhesion promoter (AP), based on the overall weight of the fiber reinforced composition (C), wherein the fiber reinforced composition (C) has a melt flow rate MFR.sub.2 (230 C., 2.16 kg) determined according to ISO 1133 in the range of 1.0 to 60.0 q/10 min.

Description

[0430] FIG. 1(a): schematic diagram of the CRYSTEX QC instrument

[0431] FIG. 1(b): elution of the EP copolymer sample and obtained soluble and crystalline fractions in the TREF column (column filled with inert material e.g. glass beads) (see Del Hierro, P.; Ortin, A.; Monrabal, B.; Soluble Fraction Analysis in polypropylene).

[0432] Intrinsic viscosity: The intrinsic viscosity (IV) was measured according to DIN ISO 1628/1, October 1999, in Decalin at 135 C.

[0433] VOC/Fog emission was measured according to VDA 278:2002 on injection moulded test specimen and on the granulated compounds. The volatile organic compounds are measured in toluene equivalents per gram. The fogging is measured in hexadecane equivalents per gram.

[0434] The measurements were carried out with a TDSA supplied by Gerstel using helium 5.0 as carrier gas and a column HP Ultra 2 of 50 m length and 0.32 mm diameter and 0.52 m coating of 5% Phenyl-Methyl-Siloxane.

[0435] The VOC-Analysis was done according to device setting 1 listed in the standard using following main parameters: flow mode splitless, final temperature 90 C.; final time 30 min, rate 60K/min. The cooling trap was purged with a flow-mode split 1:30 in a temperature range from 150 C. to +280 C. with a heating rate of 12 K/sec and a final time of 5 min. The following GC settings were used for analysis: 2 min isothermal at 40 C. heating at 3 K/min up to 92 C., then at 5 K/min up to 160 C., and then at 10 K/min up to 280 C., 10 minutes isothermal; flow 1.3 ml/min.

[0436] The fog analysis was done according to device setting 1 listed in the standard using following main parameters: flow-mode splitless, rate 60 K/min; final temperature 120 C.; final time 60 min. The cooling trap was purged with a flow-mode split 1:30 in a temperature range from 150 C. to +280 C. with a heating rate of 12 K/sec. The following GC-settings were used for analysis: isothermal at 50 C. for 2 min, heating at 25 K/min up to 160 C., then at 10 K/min up to 280 C., 30 minutes isothermal; flow 1.3 ml/min.

B. Examples

[0437] 1. Catalyst Synthesis

[0438] The catalyst used was Anti-dimethylsilanediyl[2-methyl-4,8-di(3,5-dimethylphenyl)-1,5,6,7-tetrahydro-s-indacen-1-yl][2-methyl-4-(3,5-dimethylphenyl)-5-methoxy-6-tert-butylinden-1-yl]zirconium dichloride as disclosed in WO 2020/239602 A1 as ICS3.

[0439] Preparation of MAO-Silica Support

[0440] A steel reactor equipped with a mechanical stirrer and a filter net was flushed with nitrogen and the reactor temperature was set to 20 C. Next silica grade DM-L-303 from AGC Si-Tech Co, pre-calcined at 600 C. (5.0 kg) was added from a feeding drum followed by careful pressurising and depressurising with nitrogen using manual valves. Then toluene (22 kg) was added. The mixture was stirred for 15 min. Next 30 wt.-% solution of MAO in toluene (9.0 kg) from Lanxess was added via feed line on the top of the reactor within 70 min. The reaction mixture was then heated up to 90 C. and stirred at 90 C. for additional two hours. The slurry was allowed to settle and the mother liquor was filtered off. The catalyst was washed twice with toluene (22 kg) at 90 C., following by settling and filtration. The reactor was cooled off to 60 C. and the solid was washed with heptane (22.2 kg). Finally MAO treated SiO2 was dried at 600 under nitrogen flow for 2 hours and then for 5 hours under vacuum (0.5 barg) with stirring. MAO treated support was collected as a free-flowing white powder found to contain 12.2% Al by weight.

[0441] Catalyst Preparation

[0442] 30 wt.-% MAO in toluene (0.7 kg) was added into a steel nitrogen blanked reactor via a burette at 20 C. Toluene (5.4 kg) was then added under stirring. The catalyst as cited above (93 g) was added from a metal cylinder followed by flushing with 1 kg toluene. The mixture was stirred for 60 minutes at 20 C. Trityl tetrakis(pentafluorophenyl) borate (91 g) was then added from a metal cylinder followed by a flush with 1 kg of toluene. The mixture was stirred for 1 h at room temperature. The resulting solution was added to a stirred cake of MAO-silica support prepared as described above over 1 hour. The cake was allowed to stay for 12 hours, followed by drying under N.sub.2 flow at 60 C. for 2 h and additionally for 5 h under vacuum (0.5 barg) under stirring. Dried catalyst was sampled in the form of pink free flowing powder containing 13.9% Al and 0.11% Zr.

[0443] 2. Preparation of the In-Reactor Heterophasic Polypropylene Composition (HECO1) and the Propylene Copolymer (cPP)

[0444] The in-reactor heterophasic polypropylene composition (HECO1) and the propylene copolymer (cPP) were prepared in a sequential process comprising a loop reactor and one or two gas phase reactors in the presence of the above described catalyst. The reaction conditions and properties of the final polymers are summarized in Tables 1 and 2.

TABLE-US-00001 TABLE 1 Preparation of the in-reactor heterophasic polypropylene composition (HECO1) and the propylene copolymer (cPP) HECO1 cPP Prepolymerization Temperature [ C.] 18 20 Pressure [kPa] 4977 4973 Catalyst feed [g/h] 2.4 1.4 TEAL/C3 [g/t] 0.0 3.1 feed H2/C3 ratio [mol/kmol] 0.05 0.05 Residence time [h] 0.36 0.32 Loop (R1) Temperature [ C.] 70 70 Pressure [kPa] 4867 4860 H2/C3 ratio [mol/kmol] 0.43 0.14 C2/C3 ratio [mol/kmol] 1.23 30.08 MFR.sub.2 [g/10 min] 81.9 2.1 C2 [mol-%] 0.0 3.0 Residence time [h] 0.29 0.39 Split [wt.-%] 57 58 XCS [wt.-%] 0.6 0.7 GPR (R2) Temperature [ C.] 80 80 Pressure [kPa] 2500 2500 H2/C3 ratio [mol/kmol] 3.6 1.6 C2/C3 ratio [mol/kmol] 0.0 85.5 Residence time [h] Split [wt.-%] 32 42 C2 (total) [mol-%] 0.0 2.4 XCS [wt.-%] 0.75 0.5 MFR [g/10 min] 101 2.3 GPR (R3) Temperature [ C.] 70 Pressure [kPa] 2500 H2/C3 ratio [mol/kmol] 2.1 C2/C3 ratio [mol/kmol] 822 Split [wt.-%] 11 MFR [g/10 min] 87.5

TABLE-US-00002 TABLE 2 Properties of the the in-reactor heterophasic polypropylene composition (HECO1) and the propylene copolymer (cPP) after pelletiziation HECO1 cPP MFR [g/10 min] 76.2 8.3 XCS [wt.-%] 11.2 0.47 C2 [mol-%] 2.5 3.6 C2 (XCS) [mol-%] 32.5 n.d. IV (XCS) [dl/g] 2.6 n.d. Tm [ C.] 157 137 Tc [ C.] 121 100 1, 2e [mol-%] 0.7 0.8 SF [wt.-%] 10.6 0.5 C2(SF) [mol-%] 31.3 n.d. C2(CF) [mol-%] 0.0 IV [dl/g] 1.26 2.05 IV(SF) [dl/g] 2.51 n.d. IV(CF) [dl/g] 1.11 n.d. IV(SF)/IV(CF) [] 2.26 n.d. Flexural modulus [MPa] 1257 760 Charpy notched impact strength (23 C.) [kJ/m.sup.2] 3.85 9.65 Charpy notched impact strength (20 C.) [kJ/m.sup.2] 1.96 n.d. Tg(1) [ C.] 45 Tg(2) [ C.] 0 4

[0445] 3. Preparation of the Fiber Reinforced Composition (C) with HECO1

[0446] The fiber reinforced composition (0) was obtained by melt blending the in-reactor heterophasic polypropylene composition (HECO1) with the glass fibers (GF), the adhesion promoter (AP) and the additives (AD) in a co-rotating twin screw extruder. The composition and properties of the inventive and comparative examples are summarized in Table 3.

TABLE-US-00003 TABLE 3 Composition and properties of the inventive and comparative examples IE1 CE1 CE2 HECO1 [wt.-%] 77.1 98.6 HECO1a [wt.-%] 49.1 hP [wt.-%] 28.0 GF [wt.-%] 20.0 20.0 AP [wt.-%] 1.5 1.5 AD1 [wt.-%] 1.4 1.4 1.4 MFR [g/10 min] 27 19 76 Tensile modulus [MPa] 4936 4993 1298 Tensile strength [MPa] 80.3 77.9 26.3 Elongation at break [%] 3.6 3.5 10.5 VOC g/g 26 143 32 Fog g/g 92 479 104 HECO1a is the commercial heterophasic propylene copolymer EF015AE of Borealis AG prepared with a Ziegler-Natta catalyst having a xylene cold soluble content of 29.0 wt.-%, an ethylene content of 11.1 mol-% and an intrinsic viscosity of the xylene soluble fraction of 2.7 dl/g. hP is the commercial propylene homopolymer HJ120UB of Borealis AG prepared with a Ziegler-Natta catalyst having a melt flow rate MFR.sub.2 (230 C.) of 75 g/10 min, a density of 905 kg/m.sup.3 and a glass transition temperature Tg of +2 C. GF is the commercial product ECS 03 T-480H of Nippon Electric Glass Co., Ltd. having a filament diameter of 10.5 m and a strand length of 3 mm. AP is the adhesion promoter SCONA TPPP 8112 GA by Scona being a polypropylene functionalized with maleic anhydride having a maleic anhydride content of 1.4 wt.-% and a MFR (190 C., 2.16 kg) above 80 g/10 min. AD1 is a masterbatch consisting of 14.0 wt.-% Tris (2,4-di-t-butylphenyl) phosphite (Kinox-68- G by HPL Additives), 14.0 wt.-% of pentaerythrityl-tetrakis(3-(3,5-di-tert. butyl-4-hydroxyphenyl)-propionate (Irganox 1010FF by BASF), 36.0 wt.-% of carbon black (50 wt.-% masterbatch) by Borealis, and 36.0 wt.-% of the propylene homopolymer HC001A by Borealis having a density of 905 kg/m.sup.3 and a MFR (230 C., 2.16 kg) of 3.2 g/10 min.

[0447] 4. Preparation of the Compounded Heterophasic Polypropylene Composition (HECO2)

[0448] Preparation of the Fiber Reinforced Composition (C) with HECO2

[0449] The propylene copolymer (cPP) was melt blended with the elastomeric ethylene copolymer (E), the glass fibers (GF), the adhesion promoter (AP), optionally the low density polyethylene (LDPE) and the additives (AD) in a co-rotating twin screw extruder. The composition and properties of the inventive and comparative examples are summarized in Table 4.

TABLE-US-00004 TABLE 4 Composition of the inventive and comparative examples IE2 IE3 CE3 CE4 cPP [wt.-%] 47 47 cPPa [wt.-%] 47 cPPb [wt.-%] 78.45 E [wt.-%] 30 15 30 LDPE [wt.-%] 15 GF [wt.-%] 20 20 20 20 AP [wt.-%] 1.5 1.5 1.5 1.0 AD2 [wt.-%] 1.5 1.5 1.5 AD3 [wt.-%] 0.55 MFR [g/10 min] 2.8 3.6 2.8 4.0 Tensile modulus [MPa] 2671 2758 2437 3807 Tensile strength [MPa] 45.7 46.5 42.6 64.4 Elongation at break [%] 11.6 11.0 10.2 5.6 VOC g/g 35 42 n.d. 28 Fog g/g 103 106 n.d. 74 cPPa is the commercial propylene ethylene random copolymer RD208CF of Borealis AG prepared with a Ziegler-Natta catalyst having an ethylene content of 7.3 mol-%, a melt flow rate MFR.sub.2 (230 C., 2.16 kg) determined according to ISO 1133 of 8.0 g/10 min and a melting temperature Tm of 140 C. cPPb is the metallocene propylene ethylene random copolymer according to example IE1 of WO 2015/121160 A1 having an ethylene content of 4.1 mol-% and a melt flow rate MFR.sub.2 (230 C., 2.16 kg) determined according to ISO 1133 of 4.0 g/10 min. E is the commercial copolymer of ethylene and 1-octene Queo 8201 of Borealis AG having a melt flow rate (190 C., 2.16 kg) determined according to ISO 1133 of 1.1 g/10 min, a melting temperature Tm of 72 C., a glass transition temperature Tg of 52 C., a density of 882 kg/m.sup.3 and an ethylene content of 75.5 wt.-%. LDPE is the commercial copolymer of ethylene and vinyl acetate OE5328 of Borealis AG having a melt flow rate 190 C., 2.16 kg) determined according to ISO 1133 of 3.0 g/10 min, a density of 950 kg/m.sup.3 and a vinyl acetate content of 28.0 wt.-%. AD2 is a masterbatch consisting of 20.0 wt.-% of Erucamide (Finawax-E by Fine Organics), 6.6 wt.-% of Tris(2,4-di-tert.-butylphenyl)phosphite (Irgafox 168 by BASF), 6.6 wt.-% of pentaerythrityl-tetrakis(3-(3,5-di-tert. butyl-4-hydroxyphenyl)-propionate (Irganox 1010FF by BASF), 33.3 wt.-% of carbon black (50 wt.-% masterbatch) by Borealis, and 33.3 wt.-% of the propylene homopolymer HC001A by Borealis having a density of 905 kg/m.sup.3 and a MFR (230 C., 2.16 kg) of 3.2 g/10 min. AD3 is a masterbatch consisting of 18.18 wt.-% of Tris(2,4-di-tert.-butylphenyl)phosphite (Irgafox 168 by BASF), 36.36 wt.-% of pentaerythrityl-tetrakis(3-(3,5-di-tert. butyl-4-hydroxyphenyl)-propionate (Irganox 1010FF by BASF) and 45.45 wt.-% Di-stearyl-thio-propionate (Irganox PS-802 FL by BASF).