(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date WO 2016/198344 Al 15 December 2016 (15.12.2016) P O P C T (51) International Patent Classification: (81) Designated States (unless otherwise indicated, for every C08L 23/12 (2006.01) kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, (21) International Application Number: BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM, PCT/EP20 16/062740 DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, (22) International Filing Date: HN, HR, HU, ID, IL, IN, IR, IS, JP, KE, KG, KN, KP, KR, 6 June 2016 (06.06.2016) KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, (25) Filing Language: English PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, (26) Publication Language: English SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (30) Priority Data: 15 17 1854. 1 12 June 2015 (12.06.2015) (84) Designated States (unless otherwise indicated, for every 15 188160.4 2 October 201 5 (02. 10.2015) kind of regional protection available): ARIPO (BW, GH, GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, (71) Applicant: SABIC GLOBAL TECHNOLOGIES B.V. TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, [NL/NL]; Plasticslaan 1, 4612 PX Bergen op Zoom (NL). TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, (72) Inventors: LECOUVET, Benoit, Therese, Philippe; c/o LV, MC, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, SABIC Intellectual Property Group, P.O. Box 3008, 6160 SM, TR), OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ, GA Geleen (NL). BATINAS-GEURTS, Aurora, Alexan¬ GW, KM, ML, MR, NE, SN, TD, TG). dra; c/o SABIC Intellectual Property Group, P.O. Box 3008, 6160 GA Geleen (NL). BERCX, Rick, Robert, Em- Published: ilie; c/o SABIC Intellectual Property Group, P.O. Box — with international search report (Art. 21(3)) 3008, 6 160 GA Geleen (NL). (74) Agent: SABIC INTELLECTUAL PROPERTY GROUP; P.O. Box 3008, 6160 GA Geleen (NL). (54) Title: PROCESS FOR MANUFACTURE OF LOW EMISSION POLYPROPYLENE (57) Abstract: The present invention relates to a heterophasic propylene copolymer consisting of a propylene-based matrix and a dispersed ethylene-a-olefin copolymer, wherein the heterophasic propylene copolymer has a melt flow rate of at least 40 g/lOmin as determined in accordance with ISO 1 133 (230°C, 2.16 kg) and a FOG value of at most 350 g/g as determined by VDA 278. PROCESS FOR MANUFACTURE OF LOW EMISSION POLYPROPYLENE The present invention relates to a process for the manufacture of a heterophasic propylene copolymer having a target melt flow rate of from at least 40 g/1 Omin as determined in accordance with ISO 1133 (230°C, 2.16 kg) and having low FOG values as determined in accordance with VDA 278. Heterophasic propylene copolymers, also known as impact propylene copolymers or propylene block copolymers, are an important class of polymers due to their attractive combination of mechanical properties, such as impact strength over a wide temperature range and their low cost. These copolymers find a wide range of applications ranging from the consumer industry (for example packaging and housewares), the automotive industry to electrical applications. One of the requirements for propylene polymers such as heterophasic propylene copolymers in automotive interior applications is that it has a relatively low emission of low molecular weight materials. In other words, such propylene polymers may contain only a very low amount of low molecular weight oligomers, because such low molecular weight materials can cause an unpleasant odor, a sticky feeling of the surface or may condense against windscreens thereby causing a reduced visibility. One of the requirements related to such emission is laid down in the VDA 278 standard. The emission as determined in that standard is referred to as the FOG value. For example car manufacturers may require that the FOG value is typically at most 500 µg g, more in particular at most 400 µg g. With requirements becoming more strict in the future FOG values of at most 350 µg g or even at most 250 µg g are desirable. Currently a method for reducing FOG emission involves maintaining polypropylene pellets or powders at a certain elevated temperature for a certain amount of time. For example polypropylene pellets or powders may be continuously fed to the top of a silo where the polypropylene is preferably contacted in counter-flow with a stream of hot gas, which may be for example nitrogen or dried air. At the bottom of the silo polypropylene having a reduced FOG value is then continuously withdrawn. This process is often referred to as venting, degassing or purging. It is noted that this venting, degassing or purging should not be confused with the removal of unreacted monomer as is usually carried out directly after polymerisation. Venting, degassing or purging processes are disclosed for example in GB 1272778, WO 02/088194, WO2004/039848 and US 6,218,504. Other methods to remove low molecular weight materials also exist, among which are steam stripping or chemical treatment. A disadvantage of a venting step is that such an extra step adds cost to the final heterophasic propylene copolymer product. In particular it is noted that heterophasic propylene copolymers having a relatively high initial FOG value generally need to be maintained for a longer period of time in the venting equipment. Such a longer residence time not only increases the overall cost, but may also have a negative effect on the optical properties of the material in that the heterophasic propylene copolymer suffers from more yellowing due to partial thermal degradation. Another trend in industry is down-gauging: the desire to more efficienty produce materials with at least a similar property profile, e.g. producing with less material and/or by using less energy. In order to use less energy for injection molding, a higher melt flow rate of the polymer, in this case heterophasic propylene copolymer is desired. A higher melt flow rate will enable faster injection molding and hence will reduce the energy needed per produced article. Also, it is a cost-effective solution as this allows for a shorter cycle time and therefore increases productivity. However, typically a higher melt flow rate also increases the FOG due to the presence of a larger low molecular weight fraction, which fraction can be more easily emitted from a composition/article prepared therefrom. It is therefore an object of the present invention to provide a heterophasic propylene copolymer having low FOG values and a high melt flow rate, while maintaining desirable mechanical and rheological properties. Accordingly, the present invention provides a heterophasic propylene copolymer consisting of a propylene-based matrix and a dispersed ethylene-oolefin copolymer, wherein the heterophasic propylene copolymer has a melt flow rate of at least 40 g/10min as determined in accordance with ISO 1133 (230°C, 2.16 kg) and a FOG value of at most 350 µg g as determined by VDA 278. Preferably, the melt flow rate of the heterophasic propylene copolymer is at least 40 dg/min, for example at least 50 dg/10min or at least 60 dg/10min, and/or at most 90 dg/min, for example at most 80 dg/min or at most 70 dg/min (ISO 1133, 230°C, 2.16 kg). Preferably, the melt flow rate of the heterophasic propylene copolymer is 50-80 dg/min (ISO 1133, 230°C, 2.16 kg).The melt flow rate of at most 80 dg/min or at most 70 dg/min is advatangeous for even more reduced FOG values. Preferably, the heterophasic propylene copolymer of the invention is prepared according to the process for the manufacture of the heterophasic propylene copolymer as described herein. In another aspect, the present invention provides a process for the manufacture of the heterophasic propylene copolymer according to the invention consisting of a propylene- based matrix and a dispersed ethylene-oolefin copolymer, wherein the heterophasic propylene copolymer has a target melt flow rate of at least 40 g/10min as determined in accordance with ISO 1133 (230°C, 2.16 kg) and a FOG value of at most 350 µg/g as determined by VDA 278, comprising the steps of: I) polymerizing monomers to obtain an intermediate heterophasic propylene copolymer having an intermediate melt flow rate and II) visbreaking said intermediate heterophasic propylene copolymer, for example during extrusion directly after step I), to obtain the heterophasic propylene copolymer having said target melt flow rate and said FOG value and wherein the ratio of the target melt flow rate to the intermediate melt flow rate is more than 1, wherein step I) is performed in the presence of a catalyst system comprising a Ziegler- Natta catalyst and at least one external electron donor chosen from the group of a compound having a structure according to Formula III (R )2N-Si(OR ) 3 , a compound 2 having a structure according to Formula IV: (R )Si(OR 3 ) 3 and mixtures thereof wherein each of R9 , R9 ,R92 and R93 groups are each independently a linear, branched or cyclic, substituted or unsubstituted alkyl having between 1 and 10 carbon atoms, preferably wherein R9 , R9 ,R92 and R93 groups are each independently a linear unsubstituted alkyl having between 1 and 8 carbon atoms, preferably ethyl, methyl or n-propyl, more preferably wherein the at least one external electron donor is chosen from the group of diethylaminotriethoxysilane (DEATES), n-propyl triethoxysilane, (nPTES), n-propyl trimethoxysilane (nPTMS) and mixtures thereof.