ULTRA-LIGHT SKIING BOOTS

Abstract

A composition contains a thermoplastic polyurethane (TPU-1), obtained or obtainable by reaction of an isocyanate composition (IZ) containing MDI with a polyol composition (PZ), and hollow glass microspheres. The polyol composition (PZ) contains at least one polyol (P1) selected from polytetrahydrofurans having an average molecular weight Mn in the range from 900 to 2,000 g/mol. The polyol composition (PZ) also contains a chain extender (KV1), selected from 1,2-ethandiol, 1,3-propanediol, 1,4-butanediol and 1,6-hexanediol. Ski shoes, preferably ski boots, particularly preferably the outer shell of a ski boot, can be based on such a thermoplastic polyurethane. Corresponding processes can be used for producing ski shoes.

Claims

1-10. (canceled)

11: A process for producing a ski shoe or a part of a ski shoe, the process comprising: (A) providing a composition comprising (i) a thermoplastic polyurethane (TPU-11) obtained or obtainable by reaction of an isocyanate composition (IZ) comprising MDI with a polyol composition (PZ), wherein the polyol composition (PZ) comprises at least one polyol (P1), which is at least one polytetrahydrofuran having an average molecular weight Mn in the range from 1200 to 2000 g/mol, and a chain extender (KV1), selected from the group consisting of 1,2-ethandiol, 1,3-propanediol, 1,4-butanediol, and 1,6-hexanediol; and (ii) hollow glass microspheres; and (B) producing a ski shoe or a part of a ski shoe from the composition provided in (A).

12: The process according to claim 11, wherein the at least one polyol (P1) is at least one polytetrahydrofuran having an average molecular weight Mn in the range from 1300 to 1900 g/mol.

13: The process according to claim 11, wherein the chain extender (KV1) is 1,4-butanediol.

14: The process according to claim 11, wherein the thermoplastic polyurethane (TPU-1) has a hard phase fraction of greater than 0.40, wherein the hard phase fraction is defined by the following formula $\mathrm{Hard}\mathrm{phase}\mathrm{fraction}=\left\{\underset{x=1}{\overset{x}{.Math.}}\left[\left(m_{\mathrm{KVx}}/M_{\mathrm{KVx}}\right)*M_{\mathrm{Iso}}+m_{\mathrm{KVx}}\right]\right\}/m_{\mathrm{ges}}$ having the following definitions: M.sub.KVx: molar mass of a chain extender x in g/mol, m.sub.KVx: mass of the chain extender x in g, M.sub.Iso: molar mass of an employed isocyanate in g/mol, m.sub.ges: total mass of all starting materials in g, and x: number of chain extenders.

15: The process according to claim 11, wherein a glass of the hollow glass microspheres is a soda-lime borosilicate glass.

16: The process according to claim 11, wherein the hollow glass microspheres have an average diameter in the range of from 5 to 100 μm.

17: The process according to claim 11, wherein the composition comprises the hollow glass microspheres in an amount of from 1 to 25 weight %, based on a sun of the components (i) and (ii).

18: The process according to claim 11, wherein in (B), the producing comprises injection molding the composition.

19: A ski shoe or part of a ski shoe, obtained or obtainable according to the process according to claim 11.

Description

EXAMPLES

1. Materials Used

[0138] iMK16 Glass bubbles from 3M Speciality Materials: GLASS BUBBLES IM16K, Target crush strength (90% survival): 16000 psi, true density of 0.46 g/cm.sup.3, particle size distribution (10%) 3M QCM 193.2:12 μm by volume, particle size distribution (50%) 3M QCM 193.2:20 μm by volume, particle size distribution (90%) 3M QCM 193.2:30 μm by volume, effective top size, 3M QCM 193.2:40 μm by volume, alka-linity <0,5 meq/g. [0139] TPU 1: Elastollan 1157D13U from BASF Polyurethanes GmbH Lemförde: TPU with Shore hardness 57D, based on PTHF with an average molecular weight (Mn) of 1700 Dalton, 1,4-butanediol, MDI

2. Example 2—Production of Materials

[0140] The materials according to examples 1 to 4 were produced using a ZE 40 A twin-screw extruder from company Berstorff with a 35 D screw divided into 10 barrels. The formula-tions for the individual materials are summarized in table 1.

TABLE-US-00001 TABLE 1 Formulations Material/example 1 2 3 4 EB inv. Example/ VB EB EB EB VB comp. example TPU 1 100 95 90 85 Glass Bubbles — 5 10 15 3M IM16K Sum [%] 100 100 100  100 

3. Determination of Properties

[0141] Mechanical properties were determined on injection molded bodies. The properties for the individual materials are summarized in tables 2, 3 and 4.

TABLE-US-00002 TABLE 2 mechanical properties example example example example 1 (VB) 2 (EB) 3 (EB) 4 (EB) Amount hard 53 5 — — segment MFR 230° C./ 30 59 71 58 2.16 Kg [g/10 min] Density 1.15 1.08 1.01 0.95 [g/cm.sup.3] Hardness 57 57 58 59 [Shore D] Tensile 43 25 18 17 strength [MPa] Elongation at 360 190 100 40 break [%] Tear propagation 126 121 85 74 resistance [kN/m] elastic 561 492 501 515 modulus[MPa]

TABLE-US-00003 TABLE 3 E-modulus over temperature Temperature example example example example [° C.] 1 (VB) 2 (EB) 3 (EB) 4 (EB) elastic 23 561 492 501 515 modulus[MPa] 0 662 647 624 705 −10 762 708 794 1035 −20 900 895 1190 1425 −30 949 1120 1351 1518

TABLE-US-00004 TABLE 4 impact strength example example example example 1 (VB) 2 (EB) 3 (EB) 4 (EB) Charpy impact strength 0 0 0 0   at 23° C., [kJ/m.sup.2] breaking yes/no no no no no Charpy impact strength 0 0 0 157.2  at −20° C., [kJ/m.sup.2] breaking yes/no no no no yes Charpy notched impact 0  40.7  16.5 10.5  strength at 23° C., [kJ/m.sup.2] breaking yes/no no yes yes yes Charpy notched impact 117.9   13.9   8.4 5.9 strength at −20° C., [charpy kJ/m.sup.2] breaking yes/no yes yes yes yes [0142] The examples show that the addition of glass bubbles results in a significant reduction of the density of the materials obtained. The increase of the E-modulus (%) with decreasing temperature is surprisingly low. At the same time, the materials have good mechanical properties, in particular good impact strength at low temperatures. The materials according to the invention allow to produce for example ski boots with reduced weight.

4. Methods

[0143]

TABLE-US-00005 Melt flow ratio (MFR) DIN EN ISO 1133 Density DIN EN ISO 1183-1, A Hardness [Shore D] DIN ISO 7619-1 Tensile strength DIN EN ISO 527 Elongation at break DIN EN ISO 527 Tear propagation resistance DIN ISO 34-1, B (b) elastic modulus DIN EN ISO 527 Charpy impact strength at 23° C. DIN EN ISO 179-1/1eU Charpy impact strength at −20° DIN EN ISO 179-1/1eU Charpy notched impact strength at 23° C. DIN EN ISO 179-1/1eU Charpy notched impact strength at −20° DIN EN ISO 179-1/1eU