Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
  • C08J9/0061—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof characterized by the use of several polymeric components
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
  • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
  • C08J9/22—After-treatment of expandable particles; Forming foamed products
  • C08J9/228—Forming foamed products
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L87/00—Compositions of unspecified macromolecular compounds, obtained otherwise than by polymerisation reactions only involving unsaturated carbon-to-carbon bonds
  • C08L87/005—Block or graft polymers not provided for in groups C08L1/00 - C08L85/04
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2201/00—Foams characterised by the foaming process
  • C08J2201/02—Foams characterised by the foaming process characterised by mechanical pre- or post-treatments
  • C08J2201/024—Preparation or use of a blowing agent concentrate, i.e. masterbatch in a foamable composition
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2201/00—Foams characterised by the foaming process
  • C08J2201/02—Foams characterised by the foaming process characterised by mechanical pre- or post-treatments
  • C08J2201/03—Extrusion of the foamable blend
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2205/00—Foams characterised by their properties
  • C08J2205/04—Foams characterised by their properties characterised by the foam pores
  • C08J2205/052—Closed cells, i.e. more than 50% of the pores are closed
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2377/00—Characterised by the use of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Derivatives of such polymers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2387/00—Characterised by the use of unspecified macromolecular compounds, obtained otherwise than by polymerisation reactions only involving unsaturated carbon-to-carbon bonds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2423/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers

Definitions

• the present invention concerns a closed-cell crosslinked, polyether block amide foam and more precisely a foam made from a copolymer having polyamide blocks and polyether blocks.
• the properties of said foam are, among others, high energy return, low density, high fatigue resistance, low compression strength, low dynamic shear modulus, high shape recovery, and high water vapour transmission whilst still being a closed-cell product. Such properties are unique to a closed-cell foam.
• the present invention also relates to uses of the foam.
• the patent US 3711584 describes a process and apparatus for producing a wrinkle- free, highly foamed sheet of an ethylenic resin having a uniform and fine cellular structure by causing a long strip of a sheet-like moulded article of a cross-linked ethylenic resin containing a normally solid organic blowing agent to fall downwardly and continuously transferring it in the falling direction, heating the sheet-like moulded article in transit to a foaming temperature, the heating being controlled so that a starting position of foaming along the widthwise direction of the sheet-like article will not appreciably fluctuate upwards or downwards and extending the foamed sheet-like article in the widthwise direction.
• Ethylenic resins have the disadvantage of not being permeable for water vapor and are therefore not suitable for applications where water vapor transmission is desired.
• Japanese patent application JP 56111658 is obtain a foamy body having an excellent cushion quality and a rebounding elasticity with a small quantity of raw material by a method wherein a rubber sheet containing synthetic rubber and a bubbling agent in a specific ratio is filled in a moulding mould, it is blocked with a covering mould to be heated and pressed and then, it is cooled and thereafter, a metallic mould is released.
• the process of this document results in a foam having a disadvantageously high density.
• Patent EP 81069 describes a web of a cross-linked plastic material foamed in a closed-cell structure or configuration, having substantially parallel upper and lower surfaces, wherein canals penetrate the foamed material and extend and open to at least one of said upper and lower surfaces, and wherein substances can be introduced into the canals to impart beneficial properties to the web of foamed material.
• the plastic material is polyethylene which is not water vapor transmissible.
• the patent US 4559190 describes a process for the preparation of bodies of expanded cross-linked polyethylene having closed cells.
• the patent EP 0646622 describes a plastic foam material composed of a blended resin composition which includes at least two thermoplastic resins and a silane- modified based resin.
• the blended resin composition consists essentially of 100 parts by weight of at least two thermoplastic resins, from about 1 to about 50 parts by weight of a silane-modified, cross-linked, thermoplastic resin; from about 0.001 to about 2.5 parts by weight of a crosslinking catalyst for use in a silane compound and from about 1 to about 20 parts by weight of a foaming agent.
• the thermoplastic resins are polyethylene, polypropylene or polystyrene, which are not water vapor transmissible.
• Patent application WO 9512481 describes a bilayer object comprising a lightened thermoplastic elastomer of the polyether amide type adhering by itself on a non lightened thermoplastic selected from polyether amides, polyetheresters, polyurethanes.
• the bilayer product obtained by moulding the lightened thermoplastic over the compact thermoplastic may be used in the fabrication of shoe soles.
• the density of the foam is 0.6 and is not crosslinked.
• a disadvantage is the b ⁇ ayer structure which makes the product more difficult to produce. Since the product is not crosslinked the density is unacceptably high for applications such as sports products, e.g. sports shoes.
• Patent application WO200402729 describes a waterproof/breathable moisture transfer liner for alpine, snowboard and hiking. It includes an inner liner selected from technically advanced fabrics which are carefully selected. A series of layers are provided outside the inner liner including foam material and insulated nonwoven layers, breathable membranes, a supportive mesh included in a mouldable foam, or mouldable a spacer material and an outer shell fabric.
• the foam is an open-cell foam. This has disadvantages when it comes to preventing microorganisms from permeating the foam and at the same time enabling the transmission of water vapor.
• Patent application JP 60042432 describes foamed particles for the production of a resin moulding, which is a crosslinked product of a block copolymer having crystalline polyamide segments and polyether segments, having a melt index of ⁇ 40 g/10 min and a hot xylene soluble residue of ⁇ 60%.
• a resin moulding which is a crosslinked product of a block copolymer having crystalline polyamide segments and polyether segments, having a melt index of ⁇ 40 g/10 min and a hot xylene soluble residue of ⁇ 60%.
• the resulting foam has rubber elasticity, tensile strength, low temperature properties, resistance to abrasion, chemical, water or heat, adhesiveness, dye affinity, etc.
• This foam is intended to be used where polyurethiane foams show limitations in their performances for heat insulating materials, clothes, carpets, building materials or automotive supplies. Foams produced by this process, i.e.
• thermoplastic elastomer resin comprising a crosslinked block copolymer having crystalline polyamide segments and polyether segments.
• This resin has a melt index > 0.5 g/10 min and can retain melt flowability, therefore it is mouldable, especially expansion-mouldable, has rubber elasticity, tensile strength, low temperature properties, resistance to impact, abrasion, chemical, water and heat. It also has affinity for dyes, hydrophilicity, and can be formed by melt expansion moulding.
• None of the currently existing closed-cell foams have a sufficiently high rebound height, especially at low temperature, low compressive strength at given density, or a low dynamic shear modulus. Further, they do not have a sufficiently high water vapour transmission whilst having a closed-cell structure which prevents the permeation of microorganisms and contributes to a good recovery of the foam after compression.
• foams being water transmissible, but at the same time forming a barrier for microorganisms and liquids such as liquid water.
• the foams should further have properties such as high energy return, low density, high fatigue resistance, low compression strength, low dynamic shear modulus and high shape recovery. Such properties make the foam ideally suitable for example in the fields of sports articles for breathable and/or resilient materials or in the field of medicine, e.g. in the case of breathable plasters.
• the present inventors have now discovered a crosslinked foam made from a copolymer having polyamide blocks and polyether blocks as disclosed in claim 1. Preferred embodiments are described in the following and in the depending claims.
• the foam of the present invention has unexpected properties, a very regular cell size, uniformity and very low density.
• the present invention concerns a closed-cell crosslinked foam of a copolymer having polyamide blocks and polyether blocks and a density from 20 to 700 kg/m 3 , preferably 20 to 500 kg/m 3 , more preferably from 40 kg/m 3 to 300 kg/m 3 , the density being measured according to the method ISO 845.
• the cell size is from 0.05 to 2.0 mm, preferably from 0.1 mm to 1.0 mm.
• the cell size distribution is very uniform and the foam as a whole has no regions of ununiformity which could permit a transmission of liquid or microorganisms.
• the cells are closed.
• the foam does not undergo any further mechanical or thermal treatment (except to be adhesive bonded or thermoformed).
• closed cell in contrast to "open cell”, is known to a skilled person and means that essentially all cell walls of the foam are undamaged.
• at least 90% of the cells have undamaged cell wails, more preferably at least 95%, even more preferably more than 98%.
• a closed cell foam with about 98% or more undamaged ceils is generally obtained.
• the foam is made by a production process that consists of steps such as a) extrusion/kneading with insertion of a blowing agent or an expansion gas, followed by b) chemical or physical crosslinking, and c) foaming either through decomposition of an organic foaming agent added during the first step, or through return to equilibrium of supersaturated gas added during the first step, or through expansion of a gas added directly during extrusion (first step).
• the foam does not undergo any further mechanical or thermal treatment.
• the steps of extrusion/kneading, crosslinking and foaming can preferably be clearly separated; i.e. during extrusion preferably no foaming should occur.
• the extrusion/kneading should be performed at a low temperature.
• the compressive strength is from 90 to 170 kPa, preferably from 110 to 150 kPa (measured on foam of 240 kg/m 3 , at 25% deflection, method according to ISO 844).
• the shore hardness 0 is from 20 to 34, preferably from 23 to 32 (measured on foam of 240 kg/m 3 ).
• the thermal conductivity is from 0.038 to 0.058 VWm 0 K, preferably from 0.043 to 0.053 VWm 0 K (measured on foam of 240 kg/m 3 , method according to ISO 2581).
• the energy return is 28 to 40 cm, preferably 31 to 37 cm (measured on foam of 240 kg/m 3 , method according to ISO 8307, falling height 50 cm). Whilst being a closed-cell product, the water vapour transmission is from 100 g/m 2 /day to 10000 g/m 2 /day, preferably from 500 to 3500 g/m 2 /day (method according to ASTM E96 BW) provided there are enough hydrophilic polyether blocks, and the water absorption (dipping in water during one week) is lower than 8% vol.
• copolymer having polyamide blocks and polyether blocks these result from the copolycondensation of polyamide blocks containing reactive ends with polyether blocks containing reactive ends, such as, inter alia:
• Polyamide blocks containing dicarboxylic chain ends with polyoxyalkylene blocks containing diamine chain ends obtained by cyanoethylation and hydrogenation of aliphatic dihydroxylated alpha-omega polyoxyalkylenes known as polyether diols.
• polyamide blocks containing dicarboxylic chain ends with polyether diols the products obtained in this particular case being polyetheresteramides.
• the copolymers used in the present invention are advantageously of this type.
• the polyamide blocks containing dicarboxylic chain ends are derived, for example, from the condensation of ⁇ , ⁇ -aminocarboxylic acids, lactams or dicarboxylic acids and diamines in the presence of a chain-limiting dicarboxylic acid.
• the number-average molar mass (Mn) of the polyamide blocks is between 300 and 15 000 and preferably between 600 and 5 000.
• the mass Mn of the polyether blocks is between 100 and 6000 and preferably between 200 and 3000.
• the polymers containing polyamide blocks and polyether blocks may also comprise randomly distributed units. These polymers may be prepared by the simultaneous reaction of the polyether and the polyamide-block precursors. For example, polyetherdiol, a lactam (or an ⁇ , ⁇ -amino acid) and a chain-limiting diacid may be reacted in the presence of a small amount of water. A polymer is obtained essentially containing polyether blocks, polyamide blocks of very variable length, and also the various reagents which have reacted randomly and which are distributed randomly in the polymer chain.
• polymers containing polyamide blocks and polyether blocks are derived from the copolycondensation of polyamide and polyether blocks prepared beforehand or from a one-pot reaction, they have, for example,
• Shore D hardnesses which may be between 20 and 75 and advantageously between 30 and 70 and an intrinsic viscosity of between 0.8 and 2.5 measured in meta-cresol at 25O 0 C for an initial concentration of 0.8 g/100 ml.
• the MFIs may be between 5 and 50 (235 0 C for a 1 kg load).
• the polyetherdiol blocks are either used without modification and are copolycondensed with polyamide blocks containing carboxylic ends, or they are aminated in order to be converted into polyetherdiamines and condensed with polyamide blocks containing carboxylic ends. They may also be blended with polyamide precursors and a chain limiterto make polymers containing polyamide blocks and polyether blocks with randomly distributed units.
• the polyamide blocks containing dicarboxylic chain ends are derived, for example, from the condensation of ⁇ , ⁇ -aminocarboxylic acids, of lactams or of dicarboxylic acids and diamines in the presence of a chain- limiting dicarboxylic acid.
• ⁇ , ⁇ -aminocarboxylic acid mention may be made of aminoundecanoic acid, as examples of lactams, mention may be made of caprolactam and lauryllactam, as examples of dicarboxylic acids, mention may be made of adipic acid, decanedioic acid and dodecanedioic acid, and as an example of a diamine, mention may be made of hexamethylenediamine.
• the polyamide blocks are made of polyamide 12 or of polyamide 6.
• the polyamide blocks result from the condensation of one or more ⁇ , ⁇ -aminocarboxylic acids and/or of one or more lactams containing from 6 to 12 carbon atoms in the presence of a dicarboxylic acid containing from 4 to 12 carbon atoms, and are of low mass, i.e. they have an Mn of from 400 to "1 000.
• ⁇ , ⁇ -aminocarboxylic acids mention may be made of aminoundecanoic acid and aminododecanoic acid.
• dicarboxylic acids examples include adipic acid, sebacic acid, isophthalic acid, butanedioic acid, 1,4- cyclohexyldicarboxylic acid, terephthalic acid, the sodium or lithium salt of sulphoisophthalic acid, dimerized fatty acids (these dimerized fatty acids have a dimer content of at least 98% and are preferably hydrogenated) and dodecanedioic acid HOOC-(CH 2 )io-COOH.
• lactams which may be mentioned are caprolactam and lauryllactam.
• Polyamide blocks obtained by qondensation of lauryllactam in the presence of adipic acid or dodecanedioic acid and with an Mn of 750 have a melting point of 127-130 0 C.
• the polyamide blocks result from the condensation of at least one ⁇ , ⁇ -aminocarboxylic acid (or a lactam), at least one diamine and at least one dicarboxylic acid.
• the ⁇ , ⁇ -aminocarboxylic acid, the lactam and the dicarboxylic acid may be chosen from those mentioned above.
• the diamine may be an aliphatic diamine containing from 6 to 12 atoms and may be arylic and/or saturated cyclic.
• hexamethylenediamine piperazJne, 1- aminoethylpiperazine, bisamino-propylpiperazine, tetramethylenediamine, octamethylenediamine, decamethylenediamine, dodecamethylenediamine, 1,5- diaminohexane, 2,2,4-trimethyl-1,6-diaminohexane, diamine polyols, isophoronediamine (IPD), methylpentamethylenediamine (MPDM), bis(aminocyclohexyl)methane (BACM) and bis(3-methyl-4-aminocyclohexyl)methane (BMACM).
• IPD isophoronediamine
• MPDM methylpentamethylenediamine
• ALM bis(aminocyclohexyl)methane
• BMACM bis(3-methyl-4-aminocyclohexyl)methane
• the various constituents of the polyamide block and their proportion may be chosen in order to obtain a melting point of less than 150 0 C and advantageously between 90 0 C and 135 0 C.
• Copolyamides with a low melting point are disclosed in patents US 4483 975, DE 3 730 504 and US 5 459 230, and the same proportions of the constituents are adopted for the polyamide blocks.
• the copolymers having polyamide blocks and polyether blocks are made of : PA 12 (PA: polyamide) and PEG (PEG: polyethylene glycol), PA 12 and PTMG (PTMG: polytetramethylene glycol), PA 6 and PTMG, PA 6 and PEG, copolyamide blocks and PEG, copolyamide blocks and PTMG.
• the polyether blocks may represent 5% to 85% by weight of the copolymer containing polyamide and polyether blocks.
• the polyether blocks may contain units other than ethylene oxide units, such as, for example, propylene oxide or polytetrahydrofuran (which leads to polytetramethylene glycol sequences). It is also possible to use simultaneously PEG blocks, i.e. those consisting of ethylene oxide units, PPG blocks, i.e. those consisting of propylene oxide units, and PTMG blocks, i.e. those consisting of tetramethylene glycol units, also known as polytetrahydrofuran. PPG or PTMG blocks are advantageously used.
• the amount of polyether blocks in these copolymers containing polyamide and polyether blocks is advantageously from10% to 50% by . weight of the copolymer and preferably from 35% to 50%.
• copolymers containing polyamide blocks and polyether blocks may be prepared by any means for attaching the polyamide blocks and the polyether blocks.
• two processes are essentially used, one being a 2-step process, the other a one-step process.
• the 2-step process consists firstly in preparing polyamide blocks containing carboxylic ends by condensation of the polyamide precursors in the presence of a chain-limiting dicarboxylic acid and then, in a second step, in adding the polyether and a catalyst.
• the polyether and a catalyst are then added.
• the polyether may be added in one or more portions, as may the catalyst.
• the catalyst is defined as being any product which facilitates the bonding of the polyamide blocks and the polyether blocks by esterification.
• the catalyst is advantageously a derivative of a metal (M) chosen from the group formed by titanium, zirconium and hafnium. This process and these catalysts are disclosed in patents US 4332 920, US 4230 838, US 4 331 786 US 4- 252 920 JP 07145368A, JP 06287547A and EP 613919.
• all the reagents used in the two-step process i.e. the polyamide precursors, the chain-limiting dicarboxylic acid, the polyether and the catalyst, are blended. These are the same reagents and the same catalyst as in the two-step process disclosed above. If the polyamide precursors are only lactams, it is advantageous to add a small amount of water.
• the copolymer essentially has the same polyether blocks and the same polyamide blocks, but also a small portion of different reagents which have reacted randomly and which are distributed randomly in the polymer chain.
• a blend of (i) a copolymer having polyamide blocks and polyether blocks and (ii) a polyamide or a copolyamide.
• the polyamide is of the same type as the polyamide of the polyamide block.
• Both a) and b) alternatives can contain crosslinking co-agents or promoters as described in the literature to control the crosslinking network and density.
• a heated press In a heated press. Constrained expansion. An in-mould expansion or expansion in a heated press can be performed according to the present invention. The expansion is in this case preferably conducted with an extruded sheet or a kneaded felt cut to the necessary size to fill the mould. Unlike in JP 60042432, however, the expansion is not conducted with foam particles or beads to laminate or sinter in the press or mould.
• the foam of the present invention can be shaped by pressforming (i.e. by preheating, placing into a mould, closing of the mould, and allowong to cool down in the closed mould), vacuumforming, embossing and/or over-injection.
• Sports gloves padding (goalkeepers, boxing, etc): Antislip, energy return, roll product, easier.
• Immersion suits Shape recovery, elasticity, thermal insulation, tear resistance.
• Rebound layer for table tennis rackets (as only layer or in combination with other layers, for instance for protection): excellent grip/antislip (for spin-effect on ball), easy to cut and bond.
• Ski poles As golf clubs.
• Sports bat grips As golf clubs.
• Snowboard and windsurf pads Antislip, surface resistance, easy to stick.
• Saddles for bicycles: Cushioning, comfort, compression set, dynamic properties.
• Antislip coated tape construction or automotive: Antislip property, high surface tension, good touch.
• Lingerie articles (bra cup): Elasticity, wash resistance, no crease, breathable.
• Mouse mats Antislip feature, printability (no need of printed film).
• Soft keyboards and buttons Shape recovery, nice touch, vacuumformability, fatigue resistance.
• Gaskets Conformability, temp, resistance, vibration damping.
• Flexographic printing rolls Elasticity, energy return, fatigue resistance.
• Single and double side adhesive coated tapes Conformability, elasticity, shape recovery.
• Orthopaedic insoles/inlays Mechanical properties, touch, fatigue resistance.
• Footwear insoles/insocks Light weight, compression set, rebound properties.
• Footwear midsoles Light weight, compression set, rebound properties.
• Footwear lining Waterproof, but water vapour breathable, thermoformable, thermal insulation.
• Breathable footwear midsole Waterproof, but water vapour breathable, thermoformable, thermal insulation, cushioning and rebound properties.
• Heel inserts Compression set, fatigue resistance, rebound features.
• Transdermal pads Water vapour breathable, skin friendly, elastic.
• Fig. 1 An apparatus used for testing the dynamic shear modulus
• Fig. 2 A diagram showing the dynamic shear modulus and the density of foams according to the present invention and the prior art.
• Fig. 3 A diagram showing the compressive strength and the deflection of foams according to the present invention and the prior art.
• Fig. 4 A diagram showing the shape recovery (tensile strength and tensile elongation) of foams according to the present invention and the prior art.
• Fig. 5 A diagram showing the water absorption as a function of time of a foam according to the present invention.
• Fig. 6 A diagram showing the energy return of foams according to the present invention and the prior art.
• Fig. 7 A diagram showing the fatigue resistance of foams according to the present invention and the prior art.
• Fig.8 Another diagram showing the fatigue resistance of foams according to the present invention and the prior art.
• PEBAX® FOAM means a foam according to the invention.
• the dynamic shear modulus of the foam according to the invention is lower than that of other closed-cell products, and is in the same region as partly closed-cell foams. Please state which foams in the figure are closed-cell and which are partly closed-cell.
• the compressive strength was determined on different foams according to ISO 844.
• the foam according to the present invention had a density of 240 kg/m 3 .
• Fig. 3 shows that the foam according to the present invention has a lower compressive strength than other known closed-cell products. It is almost as low as the compressive strength of partly closed-cell products. Please state which foams in the figure are closed-cell and which are partly closed-cell.
• the shape recovery was tested performing a tensile test up to 1500 kPa, then returning to 0 kPa and measurement of the remaining length.
• Fig. 4 shows that the remaining strain after applying a tensile load up to- 1500 kPa, and releasing it, is much lower for the foam according to this invention, in comparison with polyolefine foams of similar density.
• the level of water vapour transmission can vary between 100 and 10000 g/m 2 /day. Examples of results obtained (measured according to ASTM E96E 38°C /90% relative humidity (RH)):
• a foam of a copolymer having PA 12 blocks of Mn 600 and PTMG blocks of Mn 2000 with an area weight of 160 g/m 2 has a WVT value of 1276 g/m 2 /day;
• a foam of a copolymer having PA 12 blocks of Mn 1000 and PTMG blocks of Mn 1000 with an area weight of 180 g/m 2 has a WVT value of 676 g/m 2 /d;
• a foam of a copolymer having PA 12 blocks of Mn 1500 and PEG blocks of Mn 1500 with an area weight of 460 g/m 2 has a WVT value of 1400 g/m 2 /d
• - A foam of a copolymer having 6.10 /11 copolyamide blocks and PEG blocks (PEG is 40% by weight of the copolymer) with an area weight of 155 g/m 2 has a WVT value of 2207 g/m 2 /d;
• No other closed-cell foam has such high water-vapour transmission values.
• the combination of such specific characteristics as cushioning, closed-cell structure and water vapour transmission is unique and makes the foam according to this invention a product of high potential for so-called "breathable-waterproof midsoles.
• Fig. 5 shows the water absorption as a function of time, the uptake of water after immersion of the foam into liquid water was measured.
• the foam according to the present invention takes up less than 4 vol% water after dipping for one whole week in water.
• Input compression 50% at 1 Hz and 10 Hz, at room temperature.
• Output recording of the compressive force, then converted in compressive strength.
• PEBAXFOAM the foam according to this invention
• Poron 50 a partly open cell foam of similar hardness
• Fig. 8 shows the development of fatigue resistance over the number of cycles performed. This chart shows that the foam according to this invention shows the lowest strength loss over a high number of cycles, and has therefore a better fatigue resistance, even better than partly closed-cell foams.

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
• Adhesive Tapes (AREA)
• Golf Clubs (AREA)
• Footwear And Its Accessory, Manufacturing Method And Apparatuses (AREA)

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• 2004
  • 2004-10-19 EP EP04024833A patent/EP1650255A1/de not_active Withdrawn
• 2005
  • 2005-10-19 EP EP05798154A patent/EP1828290A1/de not_active Withdrawn
  • 2005-10-19 WO PCT/EP2005/011253 patent/WO2006045513A1/en not_active Application Discontinuation
  • 2005-10-19 JP JP2007537204A patent/JP2008517122A/ja not_active Withdrawn
  • 2005-10-19 TW TW094136455A patent/TW200621847A/zh unknown
  • 2005-10-19 KR KR1020077010556A patent/KR20070092204A/ko not_active Application Discontinuation
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