DE102015205191A1 - polyester blend - Google Patents

Abstract

The present invention relates to a granular polyester mixture comprising:
i) 98 to 99.99% by weight, based on the components i and ii, of a polyester of the monomers:
a) 20 to 80 mol%, based on the monomers a and b, of an aliphatic α, ω-C ₉ -C ₂₃ diacid or of a corresponding diacid derivative;
b) from 20 to 80 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or a 2,5-furandicarboxylic acid derivative;
c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol;
ii) 0.01 to 2 wt .-%, based on the components i and ii, of at least one nucleating agent.
Furthermore, the present invention relates to a process for the preparation of this polyester mixture by
In a first step the monomers:
a) 20 to 80 mol%, based on the monomers a and b, of an α, ω-C ₉ -C ₂₃ diacid or of a corresponding diacid derivative;
b) from 20 to 80 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or a 2,5-furandicarboxylic acid derivative;
c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol; to be condensed into a polyester melt i;
In a second step 0.01 to 2% by weight, based on the components i to ii, of a nucleating agent ii are added to the polyester melt i and
- In a third step, the polyester mixture is granulated.

Description

• i) 98 bis 99,99 Gew.-%, bezogen auf die Komponenten i und ii, eines Polyesters aus den Monomeren:
• a) 20 bis 80 mol%, bezogen auf die Monomere a und b, einer aliphatischen α,ω-C₉-C₂₃-Disäure oder eines entsprechenden Disäurederivats;
• b) 20 bis 80 mol%, bezogen auf die Monomere a und b, einer 2,5-Furandicarbonsäure oder eines 2,5-Furandicarbonsäurederivats;
• c) 98 bis 100 mol%, bezogen auf die Monomere a und b, 1,4-Butandiol;
• ii) 0,01 bis 2 Gew.-%, bezogen auf die Komponenten i und ii, mindestens eines Nukleierungsmittels.

The present invention relates to a granular polyester mixture comprising:

• i) 98 to 99.99% by weight, based on the components i and ii, of a polyester of the monomers:
• a) 20 to 80 mol%, based on the monomers a and b, of an aliphatic α, ω-C ₉ -C ₂₃ diacid or of a corresponding diacid derivative;
• b) from 20 to 80 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or a 2,5-furandicarboxylic acid derivative;
• c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol;
• ii) 0.01 to 2 wt .-%, based on the components i and ii, of at least one nucleating agent.

• – in einem ersten Schritt die Monomere:
• a) 20 bis 80 mol%, bezogen auf die Monomere a und b, einer α,ω-C₉-C₂₃-Disäure oder eines entsprechenden Disäurederivats;
• b) 20 bis 80 mol%, bezogen auf die Monomere a und b, einer 2,5-Furandicarbonsäure oder eines 2,5-Furandicarbonsäurederivats;
• c) 98 bis 100 mol%, bezogen auf die Monomere a und b, 1,4-Butandiol; zu einer Polyesterschmelze i kondensiert werden;
• – in einem zweiten Schritt 0,01 bis 2 Gew.-%, bezogen auf die Komponenten i bis ii, eines Nukleierungsmittels ii zu der Polyesterschmelze i zugegeben werden und
• – in einem dritten Schritt die Polyestermischung granuliert wird.

Furthermore, the present invention relates to a process for the preparation of this polyester mixture by

• In a first step the monomers:
• a) 20 to 80 mol%, based on the monomers a and b, of an α, ω-C ₉ -C ₂₃ diacid or of a corresponding diacid derivative;
• b) from 20 to 80 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or a 2,5-furandicarboxylic acid derivative;
• c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol; to be condensed into a polyester melt i;
• In a second step 0.01 to 2% by weight, based on the components i to ii, of a nucleating agent ii are added to the polyester melt i and
• - In a third step, the polyester mixture is granulated.

From the WO 2009/135921 are known polyester containing long-chain aliphatic dicarboxylic acids and 2,5-furandicarboxylic acid. However, no method is described of how granular polyesters i can be prepared because of their low crystallization tendency.

On a large scale, plastic granules are usually produced by means of strand granulation or underwater granulation. In the strand granulation, the polymer melt is drawn from the reactor or extruder strand and cooled in a cooling bath of a certain length. This cooled strand is then cut with the knife of a granulator. It is customary to obtain a cylindrical granulate with, for example, a length of 3 mm and a diameter of 2 to 4 mm.

In underwater granulation, the polymer melt is allowed to flow directly into the water via a nozzle plate and at the same time the molten droplets are knocked off with a rotating knife and cooled in the water via a cooling section. It is customary to obtain a spherical granulate with, for example, a diameter of 3 mm. By varying the nozzle diameter, smaller or larger granules with a diameter of 0.5 mm to 5 mm can be produced.

Without the addition of nucleating agents ii, no granular polyester can be produced industrially.

The use of nucleating agents such as lime or chalk has been well studied by the polyesters available on the market. Nucleating agents are often added to accelerate crystallization or shift the recrystallization point to higher temperatures. In the injection molding application, cycle times can be reduced and resources saved. The transparency of thin-walled components can also be improved by nucleation. In particular, the addition of nucleating agents can improve the processability of polymers. For injection molding applications, typically nucleating agents such as talc, chalk or alkali metal salts of carboxylic acids are used.

Whether the hitherto known nucleating agents would be able to solve the more demanding task to crystallize the polyester i with their extremely low tendency to crystallize, appeared highly questionable.

By adding 0.01 to 2 wt .-%, based on the polymer mixture of components i and ii, the polymer mixture crystallizes very well and can be isolated by granulation and thus produced on an industrial scale. This is particularly surprising, since polyesters with short-chain, aliphatic dicarboxylic acids and 2,5-furandicarboxylic acid do not crystallize after the addition of the same nucleating agent.

• a) 20 bis 80 mol%, vorzugsweise 30 bis 75 mol% und insbesondere bevorzugt 50 bis 70 mol%, bezogen auf die Monomere a und b einer aliphatischen, α,ω-C₉-C₂₃-Disäure oder eines entsprechenden Disäurederivats;
• b) 20 bis 80 mol%, vorzugsweise 25 bis 70 mol% und insbesondere bevorzugt 30 bis 50 mol%, bezogen auf die Monomere a und b, einer 2,5-Furandicarbonsäure oder eines 2,5-Furandicarbonsäurederivats; und
• c) 98 bis 100 mol%, bezogen auf die Monomere a und b, 1,4-Butandiol;

in Frage.The invention is described in more detail below:
As component i, polyesters are formed from the monomers:

• a) 20 to 80 mol%, preferably 30 to 75 mol% and particularly preferably 50 to 70 mol%, based on the monomers a and b of an aliphatic, α, ω-C ₉ -C ₂₃ diacid or a corresponding diacid derivative;
• b) 20 to 80 mol%, preferably 25 to 70 mol% and particularly preferably 30 to 50 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or of a 2,5-furandicarboxylic acid derivative; and
• c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol;

in question.

As aliphatic, α, ω-C ₉ -C ₂₃ -diacids (component a) are in particular azelaic acid, sebacic acid, brassylic acid, 1,16-C ₁₆ dicarboxylic acid or 1,18-C ₁₈ dicarboxylic acid or mixtures of these dicarboxylic acids to understand. The mentioned diacids also have the advantage that they are accessible from renewable raw materials.

2,5-furandicarboxylic acid (component b) is for example made WO 2009/135921 and WO 2013/062408 . WO 2010/077133 and WO 2007/052847 known.

Acid derivatives are to be understood as meaning C ₁ -C ₆ -alkyl esters, the methyl and ethyl esters being particularly preferred.

Among the aliphatic-aromatic polyester i are, in particular, polybutylene-2,5-furandicarboxylate-coazelate, polybutylene-2,5-furandicarboxylate-cosebacate, polybutylene-2,5-furandicarboxylate-cobrassylate and poly-butylene-2 To understand 5-furandicarboxylate-co-1,18-C ₁₈ -dicarboxylate.

In general, the polyesters i contain 0.01 to 2 wt .-%, preferably 0.1 to 1.0 wt .-% and particularly preferably 0.1 to 0.3 wt .-%, based on the total weight of the polyester , a branching agent and / or 0.1 to 1.0 wt .-%, based on the total weight of the polyester, of a chain extender. The branching agent is preferably selected from the group consisting of: a polyfunctional isocyanate, isocyanurate, oxazoline, epoxide, peroxide, carboxylic anhydride, an at least trifunctional alcohol or an at least trifunctional carboxylic acid. Particularly suitable chain extenders are difunctional isocyanates (diisocyanates), isocyanurates, oxazolines, carboxylic anhydride or epoxides.

Particularly preferred branching agents have three to six functional groups. Examples include: tartaric acid, citric acid, malic acid; Trimethylolpropane, trimethylolethane; pentaerythritol; Polyether triols and glycerin, trimesic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid and pyromellitic dianhydride. Preference is given to polyols such as trimethylolpropane, pentaerythritol and in particular glycerol. The component can be used to build biodegradable polyesters with a structural viscosity. The biodegradable polyesters are easier to process.

In the context of the present invention, a diisocyanate is primarily linear or branched alkylene diisocyanates or cycloalkylene diisocyanates having 2 to 20 carbon atoms, preferably 3 to 12 carbon atoms, eg. As 1,6-hexamethylene diisocyanate, isophorone diisocyanate or methylene bis (4-isocyanatocyclo-hexane), understood. Particularly preferred aliphatic diisocyanates are isophorone diisocyanate and in particular 1,6-hexamethylene diisocyanate.

Polyfunctional epoxides are understood as meaning, in particular, an epoxide-group-containing copolymer based on styrene, acrylates and / or methacrylates. The epoxy groups bearing units are preferably glycidyl (meth) acrylates. Copolymers having a glycidyl methacrylate content of greater than 20, particularly preferably greater than 30 and especially preferably greater than 50% by weight, of the copolymer have proven to be advantageous. The epoxy equivalent weight (EEW) in these polymers is preferably 150 to 3000, and more preferably 200 to 500 g / equivalent. The weight average molecular weight M _{w of} the polymers is preferably from 2,000 to 25,000, in particular from 3,000 to 8,000. The number-average molecular weight M _{n of} the polymers is preferably from 400 to 6,000, in particular from 1,000 to 4,000. The polydispersity (Q) is generally between 1.5 and 5. The epoxy-containing copolymers of the above type are sold for example by BASF Resins BV under the trademark Joncryl ^® ADR. Is particularly suitable as branching / chain, for example Joncryl ^® ADR 4368th

In general, it makes sense to add the branching (at least trifunctional) compounds at an earlier stage of the polymerization.

The polyesters i generally have a number average molecular weight (Mn) in the range from 5000 to 100,000, in particular in the range from 10,000 to 75,000 g / mol, preferably in the range from 15,000 to 38,000 g / mol, a weight average molecular weight (Mw) of 30,000 to 300,000, preferably 60000 to 200,000 g / mol and a Mw / Mn ratio of 1 to 6, preferably 2 to 4 on. The viscosity number according to ISO 1628-5 (measured in 0.05 g / ml solution phenol / o-dichlorobenzene (1: 1)) is between 50 and 450, preferably from 80 to 250 mL / g (measured in o-dichlorobenzene / phenol (weight ratio 50/50). The melting point is in the range of 85 to 150, preferably in the range of 95 to 140 ° C.

As already mentioned, talc (talc) and calcium carbonate are particularly preferred as nucleating agents. These nucleating agents are excellent at nucleating the polyesters i, but not shorter chain polyesters such as poly (butylene succinate-co-furandicarboxylate) or poly (butylene adipate-co-furanedicarboxylate).

Other nucleating agents such as carbon black, saccharin sodium salt, calcium silicate, sodium benzoate, calcium titanate, boron nitride, zinc salts, porphyrin, chlorine, phlorin, porphodimethine, porphomethine, bacteriochlorin, isobacteriochorin, porphyrinogen, phorbine, isotactic polypropylene or polybutylene terephthalate (PBT) may also be used in the process according to the invention. be used.

• – in einem ersten Schritt die Monomere:
• a) 20 bis 80 mol%, bezogen auf die Monomere a und b, einer α,ω-C₉-C₂₃-Disäure oder eines entsprechenden Disäurederivats;
• b) 20 bis 80 mol%, bezogen auf die Monomere a und b, einer 2,5-Furandicarbonsäure oder eines 2,5-Furandicarbonsäurederivats;
• c) 98 bis 100 mol%, bezogen auf die Monomere a und b, 1,4-Butandiol; zu einer Polyesterschmelze i kondensiert werden;
• – in einem zweiten Schritt 0,01 bis 2 Gew.-%, bezogen auf die Komponenten i bis ii, eines Nukleierungsmittels zu der Polyesterschmelze i zugegeben werden und
• – in einem dritten Schritt die Polyestermischung granuliert wird.

The process for producing a granular polyester mixture is preferably carried out by

• In a first step the monomers:
• a) 20 to 80 mol%, based on the monomers a and b, of an α, ω-C ₉ -C ₂₃ diacid or of a corresponding diacid derivative;
• b) from 20 to 80 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or a 2,5-furandicarboxylic acid derivative;
• c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol; to be condensed into a polyester melt i;
• In a second step 0.01 to 2% by weight, based on the components i to ii, of a nucleating agent are added to the polyester melt i and
• - In a third step, the polyester mixture is granulated.

The first step can be carried out batchwise or preferably continuously by literature methods (see WO 2009/135921 ). A preferred continuous process is described in U.S. Patent Nos. 4,136,359 WO2009 / 127556 described. Here, in a two-stage reaction cascade, the dicarboxylic acid derivatives are first reacted together with the diol in the presence of a transesterification catalyst to give a prepolyester in a tower reactor, the condensate being taken off in cocurrent. This prepolyester generally has a viscosity number (CV) of 50 to 100 ml / g, preferably 60 to 80 ml / g. The catalysts used are usually zinc, aluminum and in particular titanium catalysts. This prepolyester is polycondensed in a cage reactor and finally chain extended with hexamethylene diisocyanate (HDI).

In the second step, the nucleating agent (component ii) is compounded in the polymer melt, for example in an extruder. In the preferred continuous process according to WO2009 / 127556 the nucleating agent is added to the polyester melt i preferably before chain extension with HDI. The addition of the nucleating agent can advantageously be carried out via a masterbatch which, in addition to polyester i, contains from 5 to 20% by weight of nucleating agent.

The granulation (third step) is carried out - as described above - preferably via a strand granulation or underwater granulation. In this case, the polymer melt is forced through a nozzle. As a nozzle, for example, a perforated plate can be used. The polymer melt is pressed in a flooded with a liquid coolant cutting chamber. The cutting chamber surrounds the nozzle, z. B. the perforated plate and the device with which the polymer melt is divided. The size and shape of the cutting chamber is in principle freely selectable and depends on practical aspects such as size of the perforated plate, geometry of the knife, amount of coolant to be transported through the cutting chamber or throughput of polymer. The coolant used is usually water. But it can also be other coolants such as monohydric or polyhydric alcohols such. As glycol or paraffins are used.

The coolant is applied at normal pressure according to a preferred embodiment. However, the coolant may also be applied under increased pressure according to another preferred embodiment. Finally, the polymer melt is divided. For this purpose, cutting devices such as rotating blades can be provided. These are generally mounted so that they in front of the nozzle, z. B. the heated nozzle plate, rotate in the cutting chamber. The speeds are for example in the range of 300 to 5000 revolutions per minute.

There are generally very short periods between the exit of the polymer melt and the division thereof. According to the invention, these are not more than 20 ms, preferably not more than 10 ms, in particular not more than 5 ms. The granules thus obtained are then cooled. The preferred cooling rate depends on the type of polymer. According to the invention, the cooling rate is 2 to 30 ° C / s, preferably in the range of 5 to 20 ° C / s, in particular in the range of 8 to 15 ° C / s. During the cooling step, the volume ratio of granules to coolant is generally from 0.03: 1 to 0.12: 1, preferably from 0.06: 1 to 0.1: 1. In general, it is preferred if the granules thereafter have an external temperature of 100 to 200 ° C, preferably from 100 to 150 ° C. It is preferred to cool the granules in the same coolant into which the polymer melt is pressed and in which it is divided.

While the granules are cooling, they are preferably transported simultaneously to a drying device. The granules can be dried, for example, in conventional drying devices, as described in the literature. Examples of suitable drying devices are centrifugal dryers or fluidized bed dryers (see above p. 333 to p. 336).

Application-technical measurements:

The viscosity number VN was determined according to ISO 1628-5 from 01.03.1998 in 0.05 g / ml solution in phenol / dichlorobenzene (1: 1).

The thermal profiles were measured on the Differential Scanning Calorimeter (DSC) Q2000 from TA Instruments. The cooling rate was 20 K / min, the weight approximately 8.5 mg. Purge gas was helium. The evaluation of the measuring curves took place on the basis of the ISO standard 11357-2 and - 3. The temperature of crystallization at the maximum was determined as the recrystallization point T _K. The temperature of the start of crystallization was determined as T _KB .

Examples

Comparative Example 1

V-1c Preparation of poly (butylene succinate-co-furandicarboxylate) (PBSF): (Molar ratio furandicarboxylic acid: succinic acid = 70:30)

A mixture of 259.9 g of dimethylfurandicarboxylate (70 mol%), 216.3 g of 1,4-butanediol (120 mol%) and 0.27 g of tetrabutyl orthotitanate (TBOT) were placed in a 1 L four-necked flask and the apparatus was treated with nitrogen rinsed. Methanol was distilled off to an internal temperature of 190 ° C (70 minutes). Subsequently, 70.8 g of succinic acid (30 mol%) were added and water distilled off to an internal temperature of 200 ° C. Vacuum was applied (1 mbar, nitrogen flow) and heated to an internal temperature of 240 ° C to remove excess 1,4-butanediol. After 50 minutes, a torque of 21 Ncm was achieved. Then 4 g talc IT extra (1% based on polymer melt) were added to the melt and mixed well. The melt was then poured into a water bath (5 m, water temperature 20 ° C), drawn strand and tried to granulate the strand in a granulator from Fa. C. F. Scheer (type SGS50-E). The strand adhered to the knife of the granulator, no granules could be obtained.

Comparative Example 2

V-2c Preparation of poly (butylene adipate-co-furandicarboxylate) (PBAF): (Molar ratio of furandicarboxylic acid: adipic acid = 70:30)

A mixture of 259.9 g of dimethylfurandicarboxylate (70 mol%), 216.3 g of 1,4-butanediol (120 mol%) and 0.29 g of tetrabutyl orthotitanate (TBOT) were placed in a 1 L four-necked flask and the apparatus was treated with nitrogen rinsed. Methanol was distilled off to an internal temperature of 190 ° C (110 minutes). Subsequently, 86.7 g (30 mol%) of adipic acid were added and water distilled off at 200 ° C for 40 minutes. Vacuum was applied (1 mbar, nitrogen flow) and heated to an internal temperature of 240 ° C to remove excess 1,4-butanediol. After 130 minutes, a torque of 21 Ncm was achieved. Then 4.2 g of talc IT extra (1% based on polymer melt) were added to the melt and mixed well. The melt was then placed in a water bath (5 m, water temperature 20 ° C). poured, and drawn strand and tried in a granulator from Fa. CF Scheer (type SGS50-E) to granulate. The strand adhered to the knife of the granulator, no granules could be obtained.

Example 3

3c Preparation of poly (butylensebacate-co-furandicarboxylate) (PBSeF): (Molar ratio of furandicarboxylic acid: sebacic acid = 70:30)

A mixture of 259.9 g of dimethylfurandicarboxylate (70 mol%), 216.3 g of 1,4-butanediol (120 mol%) and 0.32 g of tetrabutyl orthotitanate (TBOT) were placed in a 1 L four-necked flask and the apparatus was treated with nitrogen rinsed. Methanol was distilled off to an internal temperature of 190 ° C (90 minutes). Subsequently, 121.4 g (30 mol%) of sebacic acid were added and water distilled off at 200 ° C for 60 minutes. Vacuum was applied (1 mbar, nitrogen flow) and heated to an internal temperature of 240 ° C to remove excess 1,4-butanediol. After 130 minutes, a torque of 21 Ncm was achieved. Then 4.5 g of talc IT extra (1% based on polymer melt) were added to the melt and mixed well. The melt was then poured into a water bath (5 m, water temperature 20 ° C), pulled strand and granulated in a granulator from Fa. C. F. Scheer (type SGS50-E). The nucleated polyester was easily granulated.

The polyester had a viscosity number ISO 1628-5 of 74 mL / g.

Example 4

4c Preparation of poly (butylene-C _{1 8} -1.18-dicarboxylate-co-furandicarboxylate) (PBC ₁₈ F): (molar ratio furandicarboxylic acid: _C18 dicarboxylic acid = 70:30)

A mixture of 259.9 g of dimethylfurandicarboxylate (70 mol%), 216.3 g of 1,4-butanediol (120 mol%) and 0.35 g of tetrabutyl orthotitanate (TBOT) were placed in a 1 L four-necked flask and the apparatus was treated with nitrogen rinsed. Methanol was distilled off to an internal temperature of 190 ° C (90 minutes). Subsequently, 188.4 g (30 mol%) of C ₁₈ dicarboxylic acid were added and water distilled off at 200 ° C for 60 minutes. Vacuum was applied (1 mbar, nitrogen flow) and heated to an internal temperature of 240 ° C to remove excess 1,4-butanediol. After 130 minutes, a torque of 21 Ncm was achieved. Then 5.2 g of talc IT extra (1% based on polymer melt) were added to the melt and mixed well. The melt was poured into a water bath (5 m, water temperature 20 ° C), drawn strand and granulated in a granulator from the company CF Scheer (type SGS50-E).

The nucleated polyester was easily granulated.

The polyester had a viscosity number ISO 1628-5 of 94 mL / g , Table 1: Nucleation with talc: feedstock i-1 [% by weight] i-2 [% by weight] i-3 [% by weight] i-4 [% by weight] ii-1 [% by weight] crystallization * V1a 100 0 No V1b 99.9 0.1 No V 1c 99.0 1.0 No v2a 100 0 No V 2b 99.9 0.1 No v2c 99.0 1.0 No v3a 100 0 No 3b 99.9 0.1 T _kb : 104 ° CT _k : 65.1 ° C Crystallization time: 3 min 3c 99.0 1.0 T _kb : 108 ° CT _k : 75.8 ° C Crystallization time: 2 min v4a 100 0 No 4b 99.9 0.1 T _kb : 101 ° CT _k : 60.5 ° C crystallization time: 3 min 4c 99.0 1.0 T _kb : 107 ° CT _k : 67.2 ° C crystallization time: 2 min * Crystallization was determined by the crystallization peak (exothermic) in the DSC chart.
"No" means: no crystallization peak was observed within 3 minutes at a cooling rate of 20 ° C. Table 2: Nucleation with calcium carbonate: feedstock i-1 [% by weight] i-2 [% by weight] i-3 [% by weight] i-4 [% by weight] ii-2 [% by weight] crystallization V5a 100 0 No V5b 99.0 1.0 No V6a 100 0 No V6b 99.0 1.0 No V7a 100 0 No 7b 99.0 1.0 T _kb : 99 ° CT _k : 60.5 ° C Crystallization time: 3 min V8a 100 0 No 8b 99.0 1.0 T _kb : 101 ° CT _k : 61.2 ° C Crystallization time: 3 min

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2009/135921 [0003, 0012, 0024]
• WO 2013/062408 [0012]
• WO 2010/077133 [0012]
• WO 2007/052847 [0012]
• WO 2009/127556 [0024, 0025]

Cited non-patent literature

• ISO 1628-5 [0020]
• ISO 1628-5 [0030]
• ISO standard 11357-2 [0031]
• ISO 1628-5 [0035]
• ISO 1628-5 of 94 mL / g [0038]

Claims (4)

Granular polymer mixture comprising: i) from 98 to 99.99% by weight, based on the components i and ii, of a polyester of the monomers: a) from 20 to 80 mol%, based on the monomers a and b, of an aliphatic α, ω-C ₉ -C ₂₃ diacid or a corresponding diacid derivative; b) from 20 to 80 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or a 2,5-furandicarboxylic acid derivative; c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol; ii) 0.01 to 2 wt .-%, based on the components i and ii, of at least one nucleating agent. A granular polymer blend according to claim 1, wherein the nucleating agent is calcium carbonate. A granular polymer blend according to claim 1, wherein the nucleating agent is talc. A process for the preparation of a granular polyester mixture in which - in a first step, the monomers: a) 20 to 80 mol%, based on the monomers a and b, of an α, ω-C ₉ -C ₂₃ diacid or of a corresponding diacid derivative; b) from 20 to 80 mol%, based on the monomers a and b, of a 2,5-furandicarboxylic acid or a 2,5-furandicarboxylic acid derivative; c) 98 to 100 mol%, based on the monomers a and b, 1,4-butanediol; to be condensed into a polyester melt i; In a second step 0.01 to 2% by weight, based on the components i to ii, of a nucleating agent are added to the polyester melt i and, in a third step, the polyester mixture is granulated.