ELASTOMERIC POLYMER COMPOSITIONS AND RAIL TRACK STRUCTURES AND SYSTEMS COMPRISING THE SAME

Abstract

The present invention relates to elastomeric polymer compositions comprising an acrylate and the reaction product of an acetoacetylating agent and a polyol. In particular, such elastomeric polymer compositions can be used in railway track structures. The invention also relates to a method for applying the elastomeric polymer composition in railway track structures, in particular, the method of applying the polymer composition may advantageously utilise a C-Michael addition reaction which is facilitated by the reaction product of an acetoacetylating agent and a polyol present in the polymer. The invention further relates to railway track structures and systems comprising the elastomeric polymer compositions.

Claims

1. An elastomeric polymer composition comprising an acrylate and the reaction product of an acetoacetylating agent and a polyol, and wherein the polyol comprises: a) at least one dimer fatty residue selected from a dimer fatty acid residue, a dimer fatty diol residue and a dimer fatty diamine residue: and b) at least one residue of a linear or branched C2 to C36 diacid or diol.

2. (canceled)

3. An elastomeric polymer composition to claim 1, wherein the elastomeric polymer composition does not contain isocyanate.

4. An elastomeric polymer composition of claim 1, wherein the molar ratio of the reaction product of an acetoacetylating agent and a polyol to acrylate is in a range selected from the group consisting of: from between 1:0.2 to 1:4, from between 1:0.25 to 1:3, from between 1:0.25 to 1:2.5, and from between 1:0.25 to 1:1.8.

5. An elastomeric polymer composition of claim 1, wherein the acetoacetylating agent is selected from one or more of the following: methyl acetoacetate, ethyl acetoacetate, tert-butyl acetoacetate, isopropyl acetoacetate, and isobutyl acetoacetate.

6. An elastomeric polymer composition of claim 5, wherein the reaction product of the acetoacetylating agent and the polyol comprises at most 10 wt % acetoacetylating agent.

7. An elastomeric polymer composition of claim 5, wherein the weight ratio of a) to b) in the polyol is in the range 90:10 to 30:70.

8. An elastomeric polymer composition of claim 1, wherein the dimer fatty residue content of the elastomeric polymer composition is in the range from 5 to 60% by weight.

9. An elastomeric polymer composition of claim 1, wherein the reaction product of the acetoacetylating agent and the polyol may comprisei at least 10 wt % dimer fatty residue.

10. (canceled)

11. An elastomeric polymer composition of claim 1, wherein the elastomeric polymer composition comprises an acrylate selected from one or more of a monoacrylate, a polyfunctional acrylate, an oligomeric acrylate, or derivatives thereof

12. (canceled)

13. An elastomeric polymer composition according to claim 1, comprising a filler in an amount of between 5 and 60 wt % based on the total weight of the polymer composition.

14. An elastomeric polymer composition according to claim 9, comprising one or more plasticizers.

15. (canceled)

16. (canceled)

17. (canceled)

18. A method of applying the elastomeric polymer composition of claim 1 in railway track structures, the method comprising the steps of: i) preparing a polymer composition mixture by mixing A) the reaction product of an acetoacetylating agent and a polyol and wherein the polyol comprises: a) at least one dimer fatty residue selected from a dimer fatty acid residue, a dimer fatty diol residue and a dimer fatty diamine residue; and b) at least one residue of a linear or branched C2 to C36 diacid or diol; and B) an acrylate; ii) applying the polymer composition mixture to at least one or more railway track structure component; and iii) allowing the polymer composition mixture to cure.

19. A method according to claim 18, wherein the curing of step iii) is achieved via a free radical polymerisation reaction or via a Michael addition reaction.

20. (canceled)

21. (canceled)

22. A method according to claim 18, wherein in method step ii) the polymer composition mixture is applied to three sides of the rail such that the rail is embedded on three sides by the cured polymer composition or in a body of the cured polymer composition.

23. (canceled)

24. (canceled)

25. A method of claims 18, wherein after method step i) the resulting polymer composition mixture is applied in a gap, cavity, channel, or mould.

26. (canceled)

27. (canceled)

28. (canceled)

29. (canceled)

30. (canceled)

31. (canceled)

32. The method of claim 18 wherein the acetoacetylating agent is selected from one or more of the following: methyl acetoacetate, ethyl acetoacetate, tert-butyl acetoacetate, isopropyl acetoacetate, and isobutyl acetoacetate; and the reaction productof the acetoacetylating agent and the polyol comprises at least 10 wt % dimer fatter residue.

Description

FIGURES

[0185] The invention will be further explained by means of the accompanying Figures in which:

[0186] FIG. 1 shows a simplified cross-section of an embodiment of the invention wherein a channel is filled with the composition according to the invention.

[0187] FIG. 2 shows a simplified cross-section of an alternative embodiment of the invention with an embedded rail.

[0188] FIG. 3 shows a simplified cross-section of a further embodiment where a mould (not shown) has been utilised to form the structure.

[0189] FIG. 4 shows a simplified cross-section of another embodiment wherein the composition according to the invention is used to fill a channel.

[0190] FIG. 5 shows a simplified cross-section of an alternative embodiment of an embedded rail.

[0191] FIG. 6 shows a simplified cross-section of a direct fastening structure.

[0192] FIG. 7 shows a simplified cross-section of an embedded block structure.

[0193] FIG. 8 shows a simplified cross-section of a rail component coated with a composition according to the invention.

[0194] FIG. 9 shows foam sheets fully supporting the bottom and both sides of a concrete slab in a railway track system.

[0195] FIG. 10 shows multiple smaller foam sheets supporting a concrete slab in a railway track system.

[0196] FIG. 1 shows a steel rail 1 that has been lowered in to a channel. The channel is located in a road. The road is covered with an upper layer of asphalt 4. The rail 1 is conventionally fixed using a first body of elastic polymer material 2 and a second body of elastic polymer material 3, thereby providing a strong fastening of the rail and satisfactory dampening of the noise and vibration when a train or tram runs over the rail. The bodies 2 and 3 are only partly filling the channel to allow a gap under the surface of the road. This gap is subsequently filled by the elastomeric composition according to the present invention, and the composition is allowed to cure to provide elastic polymer bodies 5. In this way the composition combines adhesion to the asphalt layer 4 of the road and to the steel rail 1 with its properties of elasticity and strength. In an alternative embodiment the polymer material in the bodies 2 and 3 may be formed from a different polymer and one or both may consist of a polyurethane composition.

[0197] In FIG. 2 a rail 21 is placed into a channel that has been provided for the rail 21. The rail 21 is fixed in its desired position by the elastomer polymer. The composition according to the present invention is mixed and applied into the channel such that the rail 21 is partly covered. The elastomeric composition is allowed to cure and an elastic polymer body 22 is thus created. After curing of the body 22 the channel is further filled with the present polymer composition to provide elastic polymer bodies 23 and 24. This embodiment is especially convenient when it is desired to have the rail 21 embedded in elastic polymer material at two different height levels, as shown by the different levels of bodies 23 and 24. If such height difference is not desired, it is also possible to fill the channel in one step so that only one body, is obtained filling the entire channel to the desired height.

[0198] To obtain the embodiment shown in FIG. 3, a mould is first created (not shown) above which a rail 31 is located such that the rail 31, provided with a rail foot 32, does not touch the bottom of the mould. The remaining space is filled with a composition according to the invention and the composition is allowed to cure to provide an elastic body 33. The mould is removed and the rail with an elastic body 33 can be used in preparing railway tracks systems. In this way, the embedded rail structure can be pre-fabricated off site, and brough on-site to lay the desired railway track system.

[0199] FIG. 4 is similar to FIG. 1, but there is no asphalt layer 4 present. Here a channel has been provided in a concrete road (not shown), into which a steel rail 41 is fixed via elastic polymer bodies 43 and 44. Since body 42 only partly fills the channel, the remaining channel is filled with a composition according to the invention, yielding an elastic body 44. The body 44 has excellent adhesion properties to the steel rail. Further, it also bonds with the concrete of the road.

[0200] FIG. 5 shows a different version of an embedded rail structure. In this embodiment a rail 51 contains a rail foot 52. The rail foot 52 is fastened to a tray 53 via connecting means 54. The tray 53 may be made from a variety of materials, such as iron or steel. The tray 53 comprises side walls 55 and 56.The rail 51, rai foot 52 and tray 53 structure, is lowered into a channel that is destined for the rail, a gap is formed between the side walls of the tray 55 and 56 and the walls of the channel. This gap is filled in two steps; in a first step a layer of the present composition is applied, which after curing provides elastic body 57, and this is followed by a second step to provide for a second body 58; this second body 58 may be of any suitable polymer material, including the present elastomer polymer although an alternative polymer could be utilised.

[0201] FIG. 6 shows a direct fastening structure wherein a rail 61 is fastened to a base via a fastening means of a plate 62 via extensions 63 and hooks 64. It is evident that alternative or additional fastening means may also be applied. Two side walls 65 and 66 are provided to form a mould between them. The rail 61 with base plate 62 is lowered into this mould without touching the bottom, to create a gap. The gap is filled with the elastomeric polymer composition according to the invention to provide an elastic layer 67.

[0202] FIG. 7 shows the use of the present invention in an embodiment, similar to the rail systems described in WO 2008/040549. It shows a rail 71 that is fastened to a block 72, made from concrete. Polymer concrete and other materials may also be used for the manufacture of the block. The rail 71 is fastened by conventional fastening means using fastening extensions 74 that are fixed to the block and hooks 73 that fasten the lower part of the rail 71. The block 72 is lowered into a tray 77 to form a gap 76. The gap 76 that is formed is then filled in two steps with the elastomeric polymer composition according to the invention. Such rail and block railway track structures may be prefabricated off site and placed in a destined location to create a railway track system. The structure positioning may be done at the desired location in the same way as described in WO 2008/040549.

[0203] FIG. 8 shows a cross-section of a rail 81 that is for a major part covered with a layer 82 made from the elastomer polymer composition according to the present invention. The rail 81 with the polymer layer 82 is prefabricated. When this rail is placed at its destined position, it is positioned in a channel without touching the walls of the channel. Concrete is cast underneath and alongside the rail 81, thus forming a railway track structure. The layer 82 that may be relatively thick, and thus provides noise and vibration damping. Alternatively, the layer 82 may be relatively thinner and thus provides electrical insulation and corrosion resistance. The rail 81 is mechanically fixated to a surface. At the top of the rail two elastic bodies 83 may be applied, which have skid resistance properties; these elastic bodies 83 are formed from alternative polymer materials and may be polyurethane or epoxy type materials.

[0204] FIG. 9 shows two rails 91 fastened by conventional means to a slab of concrete 92. Foam sheets 93 and 93 have been prefabricated from the elastomeric composition according to the present invention. The foam sheets have been prefabricated separately away from the railway track structure and were placed in their destined location before placing slab 92 and rails 91. The foam sheets offer support and vibration dampening of the railway track system. In FIG. 9, the size of the foam sheets is such that the bottom and sides of the concrete slab 92 are fully enclosed.

[0205] FIG. 10 shows two rails 101 fastened by conventional means to a slab of concrete 102. The foam sheets 103 have been prefabricated from the elastomeric polymer composition according to the present invention. The foam sheets have been prefabricated separately, away from the railway track structure and were placed in their destined location before placing slab 102 and rails 101. The foam sheets offer support and vibration dampening of the railway track system. In FIG. 10, the size of the foam sheets is such that the bottom and sides of the concrete slab 102 are not fully enclosed.

EXAMPLES

[0206] The present invention will now be described further by way of example only with reference to the following Examples. All parts and percentages are given by weight unless otherwise stated.

[0207] It will be understood that all tests and physical properties listed have been determined at atmospheric pressure and room temperature (i.e. about 20? C.), unless otherwise stated herein, or unless otherwise stated in the referenced test methods and procedures.

[0208] Materials as used in the following examples are identified as follows: [0209] 1,4-butanediola bio-based version as available ex BioAmber [0210] 1,6-hexanediolex BASF [0211] Adipic acid (C 6 dicarboxylic acid)a bio-based version ex Verdezyne [0212] Pripol? 1006 dimer fatty diacida hydrogenated C.sub.36 dicarboxylic acid ex Croda [0213] Pripol? 1013 dimer fatty diacidan unhydrogenated C.sub.36 dicarboxylic acid ex Croda [0214] Neopentyl glycolex Perstorp [0215] Trimethylolpropaneex Perstorp [0216] CaprolactoneCAPA-monomer ex Perstorp [0217] Tert-butyl acetoacetatetBAA ex Eastman [0218] Photomer? 6210a urethane acrylate ex IGM Resins [0219] Photomer? 6891a urethane acrylate ex IGM Resins [0220] Photomer? 3316an epoxy acrylate ex IGM Resins [0221] SuprasecTM 2030a methylene diphenyl diisocyanate (MDI) prepolymer ex Huntsman [0222] PTMEGTerathane?number average molecular weight 2000 ex Invista [0223] Desmophen? 2061BDa commercial polyol of polypropylene glycolnumber average molecular weight 2000 ex Covestro [0224] ImerSeal? 36Sa commercial calcium carbonate polymer filler ex Imersys [0225] Corkelast? VA-60Filled PU system based on polypropylene glycol ex. edilion)(sedra [0226] Desmodur? E15a commercial toluene diisocyanate (TDI) prepolymer ex Covestro

[0227] Test methods: [0228] Number average molecular weight was determined by end group analysis with reference to the hydroxyl value. [0229] Weight average molecular weight was determined by end group analysis with reference to the hydroxyl value. [0230] The hydroxyl value is defined as the number of mg of potassium hydroxide equivalent to the hydroxyl content of 1 g of sample and was measured by acetylation followed by hydrolysation of excess acetic anhydride. The acetic acid formed was subsequently titrated with an ethanolic potassium hydroxide solution. [0231] The acid value is defined as the number of mg of potassium hydroxide required to neutralise the free fatty acids in 1 g of sample and was measured by direct titration with a standard potassium hydroxide solution. [0232] Elongation was measured using an Instron tensile tester according to ISO 37 using dumb-bell test pieces of type 2 unless otherwise specified. [0233] Tensile Strength was measured using an Instron tensile tester according to ISO 37 using dumb-bell test pieces of type 2 unless otherwise specified. [0234] Modulus was calculated as the tensile strength required to achieve a predetermined elongation. [0235] Water absorption after 7 days immersion was measured according to ISO 62 [0236] The compression set was measured according to ISO 1856, method B (ISO 1856B) [0237] Volume resistivity was measured according to EN 62631, part 3-1 (EN 62631-3-1).

Example 1

Preparation and Examples of the Reaction Product of an Acetoacetylating Agent and a Polyol

P1Dimer Fatty Acid and Diol Containing Polyol

[0238] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 100 parts by weight of Pripol 1006 and 21 parts butanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C. under normal pressure under a nitrogen atmosphere. Under these conditions an esterification reaction was conducted to obtain a polyester polyol. The esterification reaction was conducted until the desired acid/hydroxyl value was observed; in this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 56 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 2000 g/mol and an 85% renewable content.

P2Dimer Fatty Acid, Aliphatic Diacid and Diol Containing Polyol

[0239] Three different reactions were carried out utilising Pripol 1006, adipic acid and hexanediol as the reactants; the variations in the reaction resulted in polyols of differing number average molecular weight, as detailed below.

P2A

[0240] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 50 parts by weight of Pripol 1006, 50 parts adipic acid, 68.9 parts hexanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 110 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 1000 g/mol and a 30% renewable content.

P2B

[0241] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 50 parts by weight of Pripol 1006, 50 parts adipic acid, 59 parts hexanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 56 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 2000 g/mol and a 30% renewable content.

P2C

[0242] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 50 parts by weight of Pripol 1006, 50 parts adipic acid, 56.3 parts hexanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 37 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 3000 g/mol and a 30% renewable content.

P3Dimer Fatty Acid and Glycol Containing Polyol

[0243] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 100 parts by weight of Pripol 1013 and 25 parts neopentyl glycol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 56 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 2000 g/mol and an 84% renewable content.

P4Dimer Fatty Acid, Triol and Polyol Containing Polyol

[0244] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 100 parts by weight of Pripol 1006 and 47 parts trimethylolpropane, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 282 mg KOH/g. The polyester polyol obtained was retained in the reactor and was further modified by introduction of a CAPA polyol, as per the method steps below.

[0245] The temperature of the reactor was lowered to 160? C. after which 60 parts of caprolactone (CAPA-monomer ex Perstorp) and 0.05 parts of tin (II) octoate as polymerisation catalyst, were charged. Under these conditions a ring opening polymerisation reaction was conducted until the desired acid/hydroxyl value were observed. The final polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 210 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 1000 and a 55% renewable content.

P5Dimer Fatty Acid and Diol Containing Polyol

[0246] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 100 parts by weight of Pripol 1006 and 28 parts hexanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 56 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 2000 g/mol and an 81% renewable content.

P6aDimer Fatty Acid, Diacid, Diol and Polyol Containing Polyol

[0247] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 50 parts by weight of Pripol 1006, 50 parts adipic acid and 68.5 parts hexanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 110 mg KOH/g. The polyester polyol obtained was retained in the reactor and was further modified by introduction of a CAPA polyol, as per the method steps below.

[0248] The temperature of the reactor was lowered to 160? C. after which 188 parts of caprolactone (CAPA-monomer ex Perstorp) and 0.05 parts of tin (II) octoate as polymerisation catalyst, were charged. Under these conditions a ring opening polymerisation reaction was conducted until the desired acid/hydroxyl value were observed. The final polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 56 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 2000 and a 18% renewable content.

P6bDimer Fatty Acid, Diacid, Diol and Polyol Containing Polyol

[0249] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and condenser, 50 parts by weight of Pripol 1006, 50 parts adipic acid and 68.5 parts hexanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 110 mg KOH/g. The polyester polyol obtained was retained in the reactor and was further modified by introduction of a CAPA polyol, as per the method steps below.

[0250] The temperature of the reactor was lowered to 160? C. after which 370 parts of caprolactone (CAPA-monomer ex Perstorp) and 0.05 parts of tin (II) octoate as polymerisation catalyst, were charged. Under these conditions a ring opening polymerisation reaction was conducted until the desired acid/hydroxyl value were observed. The final polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 56 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 2000 and a 12% renewable content.

Comparative Examples:

C7(Non-Dimer Containing) Polyether Based Polyol

[0251] PTMEG- Terathane? polyether based polyol with a hydroxy value of 56 mg KOH/g.

C8(Non-Dimer Containing) Diacid and Diol Containing Polyol

[0252] In a reactor equipped with a stirrer, a thermometer, a gas inlet and condenser, 100 parts by weight of adipic acid, 91 parts hexanediol, were charged. Subsequently, the temperature of the reactor was raised from ambient temperature to 220-230? C., under normal pressure in a nitrogen atmosphere. Under these conditions an esterification reaction was conducted until the desired acid/hydroxyl value was observed. In this example the polyester polyol obtained had an acid value of less than 1 mg KOH/g and a hydroxyl value of 56 mg KOH/g. The polyester polyol obtained had a calculated number average molecular weight of about 2000 g/mol and 0% renewable content.

General Method for Preparation of Reaction Product of Polyol with an Acetoacetylating Agent

[0253] Each of the polyester polyols prepared above were subsequently modified by reaction with an acetoacetylating agent containing acetoacetate.

[0254] In a reactor equipped with a stirrer, a thermometer, a gas inlet, and a condenser, 100 parts by weight of each of a polyol as prepared above and 15.8 parts by weight of tert-butyl acetoacetate (Eastman? t-BAA) were charged.

[0255] The temperature of the reactor was raised to 150-160? C. under normal pressure in a nitrogen atmosphere. Under these conditions the reaction is continued until the theoretical amount of tertiary-butanol distillate was achieved.

[0256] If necessary, a vacuum can be applied to ensure the completion of the reaction. Gel chromatography can be used to identify the reaction completion.

Example 2

Preparation and Analysis of Elastomer Polymers

[0257] Various elastomer polymers were prepared as detailed in Table 1, below. The polymers are identified by reference to the example polyol they contain as identified above, i.e. example polymer P1 contains the reaction product of polyol P1, etc. A C-Michael addition reaction performed at room temperature was employed when utilising example materials as described above in combination with one of two commercially available acrylate-based oligomers. The elastomer polymers were prepared using a 2-component process. The C-Michael crosslinking achieved within the polymer matrix can be accelerated by the use of an organic base catalyst like DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) if desirable.

[0258] The example materials and acrylate based oligomer were reacted in a molar ratio of 1:1.2 to 1.8, as noted below in Table 1. The two commercially available acrylate based oligomers tested were Photomer? 6210 (urethane acrylate ex IGM Resins) and Photomer 6891 (urethane acrylate ex IGM Resins). The resulting elastomer polymer is therefore considered to be a polyurethane based product but is advantageously prepared in the absence of isocyanate.

[0259] Comparative materials were produced utilising comparative polyol 7 and comparative polyol 8 (non-dimer containing material which required curing at an elevated temperature) as described above, and also a further material consisting of commercially available Desmophen 2061BD reacted with Suprasec? which was made to represent a commercially utilised polyether polyol in combination with a polymeric isocyanate comparative example; this is termed C9 in the table below. Hence, C9 provides an elastomeric polymer prepared by the addition of isocyanate, which is undesirable.

TABLE-US-00001 TABLE 1 Crosslinked unfilled 2-component system Example Photomer E modulus F.sub.max DL @ F.sub.max (mol ratio) (mol ratio) (MPa) (MPa) (%) P1 (1.0) 6210 (1.4) 1.2 0.9 128 P1 (1.0) 6891 (1.2) 1.5 0.9 127 P1 (1.0) 6891 (1.3) 1.5 1.0 120 P1 (1.0) 6891 (1.4) 1.5 0.9 110 P1 (1.0) 6210/3316:90/ 1.4 0.9 132 10 (1.4) P2c(1.0) 6210 (1.4) 9 2 82 P3 (1.0) 6891 (1.5) 1.4 0. 128 P3 (1.0) 6891 (1.7) 0.5 0.5 148 P3 (1.0) 6210 (1.4) 0.7 0.6 115 P3 (1.0) 6210 (1.5) 0.9 0.7 125 P3 (1.0) 6210 (1.8) 1.1 0.8 125 P4 (1.0) 6210 (1.4) 4.7 2.1 58 P6a(1.0) 6210 (1.4) 4.4 1.4 47 P6b(1.0) 6210 (1.4) 30 2.7 66 C7(1.0) 6210(1.4) 1.6 1.3 95 C8(1.0)* 6210(1.4) 1.4 0.9 99 C9 Desmophen Suprasec 0.7 0.9 260 2061BD (1.0) 2030 (1.0) *elastomer had to be prepared at an elevated temperature of between 60? C. to 90? C. to achieve curing.
When considering the mechanical data detailed in Table 1, the C-Michael polymer matrix materials which are formed at room temperature from the reaction product of an acetoacetylating agent and a polyol comprising a dimer fatty residue and a diol or diacid residue in combination with an acrylate oligomer provide E-modulus and tensile strength properties which are higher than the comparative commercial polyurethane (PU) elastomer material C9. As will be appreciated by the skilled person, although the materials in accordance with the present invention tested here provide an elongation which does not reach the high level of the commercial PU, this is the result of the higher modulus obtained. On balance, when considering the higher modulus and tensile strength obtained a commercially acceptable elongation is reached for the materials of the present invention, with the advantageous omission of isocyanate from the preparation of the polymer matrix material. Furthermore, it is known that ether bonds have a reduced thermo-oxidative stability as compared to ester bonds and therefore the presence of the polyester polyol-based backbone in the materials provided by the present invention is preferable. In addition, as noted above, the elastomer polymer based on C8 (containing no dimer) needed to be cured at elevated temperature whereas the elastomer polymer compositions in accordance with the present invention were advantageously capable of being cured at room temperature.

[0260] In a further experiment, various elastomer polymers were prepared as detailed in Table 2, below, via a C-Michael addition reaction at room temperature utilising the example reaction products of an acetoacetylating agent and a polyol as described above, in combination with one of two commercially available acrylate-based oligomers. In this case, the elastomer polymers were prepared using a 2-component process and included a filler, ImerSeal 36S. The C-Michael crosslinking achieved within the polymer matrix can be accelerated by the use of an organic base catalyst like DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) if desirable.

[0261] The reaction product of an acetoacetylating agent and a polyol and the acrylate based oligomer were reacted in a molar ratio of 1:1.2 to 1.8, as noted below in Table 2. The two commercially available acrylate based oligomers tested were Photomer? 6210 (urethane acrylate ex IGM Resins) and Photomer? 6891 (urethane acrylate ex IGM Resins). The resulting elastomer polymer is therefore a polyurethane based product but is advantageously prepared in the absence of isocyanate.

[0262] A comparative material, denoted C10 in Table 2, was produced consisting of commercially available PPG ex Sigma Aldrich and Suprasec? 2030. C10 was made to provide a polymeric isocyanate containing comparative example. Hence, C10 is a filled elastomer polymer prepared by the addition of isocyanate, which is undesirable.

TABLE-US-00002 TABLE 2 Crosslinked filled 2 component system (+29 wt % filler) Example Photomer E modulus F.sub.max DL @ F.sub.max (mol ratio) (mol ratio) (MPa) (MPa) (%) P1 (1.0) 6210 (1.4) 2.6 1.2 173 P1 (1.0) 6891 (1.2) 2.9 1.1 137 P1 (1.0) 6891 (1.3) 3.2 1.1 120 P1 (1.0) 6891 (1.4) 3.2 1.1 112 P3 (1.0) 6891 (1.4) 2.6 1 121 P3 (1.0) 6891 (1.5) 2.4 1 158 P3 (1.0) 6891 (1.7) 2.3 1.2 183 P3 (1.0) 6210 (1.8) 2.8 1.2 174 Desmophen Desmodur 2.5 1.3 160 2061DB (1.0) E15 (1.0)

[0263] When considering the mechanical data detailed in Table 2 above when a filler is included the C-Michael polymer matrix materials which are formed from the reaction product of an acetoacetylating agent and a polyol in combination with an acrylate oligomer provide E-modulus and tensile strength properties which are in a comparable range to the comparative commercial polyurethane (PU) elastomer materials. Additionally, it can be noted that the inclusion of the filler improves the elongation properties of the materials of the present invention such that they are comparable with the comparative commercial example, but with the advantageous omission of isocyanate from the polymer matrix material.

[0264] C10 is an example which is comparable to a composition such as currently used in railway track systems. For railway track systems, the E-modulus is preferably between 2.3 and 3.1 MPa. This E-modulus range offers stability of the rail/track against horizontal forces, yet the material is not too stiff, because a certain level of elasticity is required for vibration dampening.

[0265] Table 3, below, provides further information regarding varying filler amounts in a specific system.

TABLE-US-00003 TABLE 3 Crosslinked filled 2 component system (varying filler amounts) Example Photomer Filled with E modulus F.sub.max DL @ (mol ratio) (mol ratio) CaCO.sub.3 (wt %) (MPa) (MPa) F.sub.max (%) P1 (1.0) 6210 (1.4) 0 1.19 0.85 128 P1 (1.0) 6210 (1.4) 20 1.86 1.02 155 P1 (1.0) 6210 (1.4) 26 2.33 1.12 161 P1 (1.0) 6210 (1.4) 29 2.64 1.15 173 P1 (1.0) 6210 (1.4) 34 3.09 1.15 169 P1 (1.0) 6210 (1.4) 40 4.01 1.15 161

[0266] As can be seen from Table 3, compositions comprising more than 20% and less than 40%, such as between 26 and 34% filler have a suitable E-modulus for use in railway track systems. Compositions with at least 20% filler, preferably at least 26% filler have a suitable tensile strength. Suitable elongation properties are also obtained in the case of at least 20% filler.

[0267] Table 4 below provides information regarding further properties of a filled system compared to a polyurethane material that is commercially used as an embedding material in railway track systems.

TABLE-US-00004 TABLE 4 Crosslinked filled 2 component system (further properties) Water Volume resistivity Compression absorption (EN 62631-3-1) (?m) set after 7 days After storage (ISO 1856 immersion in 0.1n NaCl Method-B) Material (ISO 62) (%) Dry solution (%) Corkelast VA-60 4.50 224 .Math. 10.sup.6 35 .Math. 10.sup.6 12 Filled 0.60 583 .Math. 10.sup.6 354 .Math. 10.sup.6 3 composition according to the invention (entry with 34% filler from Table 3)

[0268] As can be seen, a filled polymer composition according to the invention surprisingly outperforms commercial PU based filled materials applied in railway track structures with respect to water absorption, volume resistivity and compression set. Thus, the elastomer polymers of the present invention are proven to be particularly suitable for use in railway track structures and systems.