JP7212544B2 - variable pad - Google Patents

Description

The present invention relates to variable pads.

As a member for adjusting the rail height on a railway track, it is inserted between a tie plate fixed on a track slab or a sleeper and a rail fixed on the tie plate, and a joint between the tie plate and the rail Variable pads are used whose thickness is adjusted to fill the gaps between them. This variable pad has a bag body portion, and after the bag body portion is inserted between the tie plate and the rail, a liquid polymerizable composition that becomes a resin by polymerizing and curing, for example, is placed inside the bag body portion. After injecting and adjusting to an arbitrary thickness, the gap between the tie plate and the rail is filled by polymerizing and curing the liquid polymerizable composition. At this time, the thickness of the variable pad is adjusted by adjusting the amount of the injected liquid polymerizable composition.

Note that track pads that are superimposed on such variable pads include those made of norbornene-based resin. WO 2013/137231 (Patent Document 1) describes a non-conjugated polyene [C-1], which is 5-ethylidene-2-norbornene (ENB), and 5-vinyl-2 in track pads for railway rails. - A technique obtained by crosslinking a composition containing an ethylene/α-olefin/nonconjugated polyene random copolymer containing a structural unit derived from a nonconjugated polyene [C-2] that is norbornene (VNB) is disclosed. ing.

WO2013/137231

By the way, some of the above-described variable pads have rib portions arranged on one side of the tie plate in the extending direction of the rail. The thickness of the rib portion is greater than the thickness of the portion of the variable pad between the tie plate and the rail, ie, the body portion.

In such a case, when the rail expands and contracts with a change in temperature, the rail moves in the extending direction of the rail, that is, it expands. In addition, the concentration of stress on the rib portion during expansion and contraction of the rail occurs at a temperature such as -20°C, which is significantly lower than about 20°C. Therefore, at such a low temperature, the variable pad is likely to be damaged due to the damage of the rib portion.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art as described above. To provide a variable pad, the thickness of which is adjusted so as to fill a gap between the two, and which is hard to be damaged even at a low temperature.

A brief outline of typical inventions disclosed in the present application is as follows.

A variable pad according to one aspect of the present invention is inserted between a tie plate and a rail fixed on the tie plate, and has a thickness adjusted to fill a gap between the tie plate and the rail. Variable pad. The variable pad has a first bag portion disposed between the tie plate and the rail, and a first resin portion filled inside the first bag portion, the first resin portion comprising: It consists of a polymer obtained by polymerizing a polymerizable composition containing a first monomer having a norbornene ring structure.

Further, as another aspect, the variable pad may be inserted between the tie plate and the rail while being superimposed on a track pad made of an elastic plate.

Further, as another aspect, the rail extends in the first direction, the variable pad is further arranged on the first side in the first direction relative to the tie plate, and the inside is the inside of the first bag body portion. and a second bag body part formed integrally with the first bag body part, and filled in the second bag body part, made of a polymer, and integral with the first resin part and a second resin portion formed in the second resin portion. The thickness of the second resin portion may be thicker than the thickness of the first resin portion.

Moreover, as another aspect, the first bag body portion may include a first inner surface layer made of polyethylene, and the first inner surface layer and the first resin portion may be adhered to each other.

（一般式（１）中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立して、水素原子又は炭素数１～２０の炭化水素基を表し、Ｒ^１とＲ^２又はＲ^３とＲ^４は共同して、アルキリデン基を形成していてもよく、Ｒ^１および／またはＲ^２とＲ^３および／またはＲ^４とが環構造を形成していてもよい。ｐは０、１又は２を表す。）
で示される化合物の１種以上よりなるものであってもよく、ノルボルネン、テトラシクロドデセン、５－エチリデンノルボルネン、８－エチリデンテトラシクロドデセン及びトリシクロペンタジエンからなる群から選択された１種以上よりなるものであってもよい。 In another aspect, the polymerizable composition further comprises a second monomer having a norbornene ring structure and of a type different from that of the first monomer, the first monomer consisting of dicyclopentadiene, The second monomer has the following general formula (1):

(In general formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R ¹ and R ² or R ³ R ⁴ may together form an alkylidene group, and R ¹ and/or R ² and R ³ and/or R ⁴ may form a ring structure, p is 0, 1 or 2.)
One or more selected from the group consisting of norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and tricyclopentadiene It may consist of.

Further, as another aspect, when the total of the content of the first monomer in the polymerizable composition and the content of the second monomer in the polymerizable composition is 100 parts by mass, the second monomer in the polymerizable composition may be 4 parts by mass or more.

Further, as another aspect, a first test piece made of a polymer and having a width of 10 mm, a thickness of 4 mm and a length of 80 mm is produced, and the produced first test piece is constrained among the first test pieces. A load in the thickness direction of the first portion of the second portion is applied from the first end of the first portion that is not restrained and is the first end of the first test piece on the side of the second portion that is not restrained. It was fixed in a cantilever shape so that the distance to the third part where it was applied was 11 mm, and the first speed of applying a load to the third part to deform it was 5 mm / min and the temperature was -20 ° C. When a bending test was performed in which a load was applied to the third portion to deform it under the conditions, the first test piece was not damaged even if the deformation amount of the third portion in the thickness direction of the first portion was 10 mm. good.

Further, as another aspect, a dumbbell shape of type 1B made of a polymer and conforming to JIS K 7161-2 "Plastics-Determination of tensile properties-Part 2: Test conditions for molded, extruded and cast plastics" A second test piece having the Among them, the third end opposite to the second side in the length direction is held by the second holding portion, and the first holding portion is held against the second holding portion so that the second test piece extends in the length direction When the second test piece breaks when the first tensile test in which the second test piece is stretched in the length direction is performed under the conditions of a second speed of relative movement of 20 mm / min and a temperature of -20 ° C. The elongation amount of the second test piece may be 23 mm or more.

Further, as another aspect, a dumbbell shape of type 1B made of a polymer and conforming to JIS K 7161-2 "Plastics-Determination of tensile properties-Part 2: Test conditions for molded, extruded and cast plastics" A third test piece having the Among them, the fifth end opposite to the third side in the length direction is held by the fourth holding portion, and the third holding portion is held against the fourth holding portion so that the third test piece extends in the length direction When the third test piece is broken when the second tensile test is performed in which the third test piece is stretched in the length direction under the conditions that the third relative movement speed is 20 mm / min and the temperature is -20 ° C. may be 38 J or more.

Further, as another aspect, a dumbbell shape of type 1B made of a polymer and conforming to JIS K 7161-2 "Plastics-Determination of tensile properties-Part 2: Test conditions for molded, extruded and cast plastics" A fourth test piece having the Among them, the seventh end opposite to the fourth side in the length direction is held by the sixth holding portion, and the fifth holding portion is held against the sixth holding portion so that the fourth test piece extends in the length direction When the fourth test piece breaks when the third tensile test is performed in which the fourth test piece is stretched in the length direction under the conditions that the fourth relative movement speed is 20 mm / min and the temperature is 60 ° C. The energy may exceed 66J.

Further, as another aspect, a fifth test piece having a width of 13 mm, a thickness of 13 mm and a length of 13 mm is prepared from the polymer, and the fifth speed of compressing the prepared fifth test piece in the length direction is Under the conditions of 1 mm / min, a compression test is performed by compressing the fifth test piece in the length direction based on JIS K 7181 "Plastics - Determination of compression properties" and JIS K 6911 "General test method for thermosetting plastics". The compressive yield point of the fifth test piece may be 52 MPa or more at any of -20°C, 23°C and 60°C.

By applying one aspect of the present invention, the tie plate is inserted between the tie plate and the rail fixed on the tie plate, and the thickness is adjusted so as to fill the gap between the tie plate and the rail. In addition, the variable pad can be made less likely to be damaged even at low temperatures.

4 is a cross-sectional view of the variable pad of the embodiment; FIG. 4 is a cross-sectional view of the variable pad of the embodiment; FIG. 4 is a cross-sectional view of the variable pad of the embodiment; FIG. FIG. 4 is a side view showing the arrangement when performing a cantilever bending test on a test piece using a cantilever bending test jig; FIG. 4 is a plan view showing the arrangement when performing a cantilever bending test on a test piece using a cantilever bending test jig; 4 is a graph showing the amount of deformation when the test piece breaks, obtained by performing a cantilever bending test on each test piece of Comparative Example 1, Comparative Example 2, and Example 1. FIG. FIG. 4 is a front view showing the arrangement when performing a tensile test on a test piece using a tensile test jig; FIG. 4 is a side view showing the arrangement when a tensile test is performed on a test piece using a tensile test jig; 5 is a graph showing the amount of elongation when the test piece breaks, obtained by performing a tensile test on each test piece of Comparative Example 3, Comparative Example 4 and Example 2. FIG. 10 is a graph showing the compression elastic modulus obtained by performing a compression test on each test piece of Comparative Example 9, Comparative Example 10 and Example 5. FIG. 10 is a graph showing compression yield points obtained by performing compression tests on test pieces of Comparative Examples 9, 10 and Example 5. FIG.

Each embodiment of the present invention will be described below with reference to the drawings.

It should be noted that the disclosure is merely an example, and those skilled in the art will naturally include within the scope of the present invention any appropriate modifications that can be easily conceived while maintaining the gist of the invention. In addition, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the embodiment, but this is only an example, and the interpretation of the present invention is not limited. It is not limited.

In addition, in this specification and each figure, the same reference numerals may be given to the same elements as those described above with respect to the previous figures, and detailed description thereof may be omitted as appropriate.

Furthermore, in the drawings used in the embodiments, hatching for distinguishing structures may be omitted depending on the drawing.

In the following embodiments, when a range is indicated as A to B, it indicates A or more and B or less, unless otherwise specified.

(Embodiment)
<Variable pad>
First, a variable pad according to an embodiment, which is one embodiment of the present invention, will be described. 1 to 3 are cross-sectional views of variable pads according to embodiments. 1 is a cross-sectional view perpendicular to the length direction of the rail, and FIGS. 2 and 3 are cross-sectional views perpendicular to the width direction of the rail. Figures 1-3 show the variable pad of this embodiment together with the tie plate, track pads and rails. Also, FIG. 3 shows an enlarged view of the vicinity of the variable pad in FIG.

As shown in FIGS. 1 to 3, the length direction of the rail RA, that is, the direction in which the rail RA extends, is the X1 direction, the width direction of the rail RA is the Y1 direction, and the top surface of the rail RA is , that is, the vertical direction is the Z1 direction.

As shown in FIGS. 1 to 3, the variable pad 1 of the present embodiment is arranged between a tie plate 2 and a rail RA fixed on the tie plate 2, with the track pad 3 positioned above in the vertical direction. It is inserted in a state in which it overlaps with the track pad 3 so as to overlap each other. The track pad 3 is made of an elastic material such as rubber. The elastic constant (Young's modulus, etc.) of the elastic body of the track pad 3 is smaller than, for example, the elastic constant of the resin portion 1b of the variable pad 1, which will be described later.

The tie plate 2 is fixed, for example by means of bolts 5, on supports 4 consisting of track slabs or sleepers and supporting the rails RA. The rail RA is fixed on the tie plate 2 using leaf spring members 6 and bolts 7, for example.

In the present embodiment, the variable pad 1 is inserted between the tie plate 2 and the rail RA in such a manner that the track pad 3 and the track pad 3 are vertically overlapped with each other. The variable pad 1 may be inserted in a state in which it is vertically overlapped with the track pad 3 so that the track pad 3 is positioned on the lower side in the vertical direction. Alternatively, the track pad 3 may not be inserted between the tie plate 2 and the rail RA, and only the variable pad 1 may be inserted. In other words, the variable pad 1 of the present embodiment can be applied when it is inserted between the tie plate 2 and the rail RA in such a manner that it overlaps with the track pad 3 in the vertical direction. is applicable when only the variable pad 1 is inserted between the tie plate 2 and the rail RA.

The thickness of the variable pad 1 is adjusted so as to fill the gap between the tie plate 2 and the rail RA. The variable pad 1 of this embodiment includes a bag body portion 1a and a resin portion 1b. The resin portion 1b is filled inside the bag portion 1a.

The resin portion 1b is obtained by polymerizing and curing the liquid polymerizable composition injected into the bag portion 1a. For example, in a state where the rail RA is raised above the tie plate 2 to a position higher than the installation position where the rail RA is installed, the track pad 3 and the bag body portion 1a are placed between the tie plate 2 and the rail RA. Insert it in a state where it is stacked up and down. Next, a liquid polymerizable composition is injected into the interior of the bag portion 1a through an injection port (not shown) formed in the bag portion 1a. Next, with the rail RA lowered to the installation position, the injected polymerizable composition is polymerized and cured so that the thickness of the resin portion 1b fills the gap between the tie plate 2 and the rail RA. , the resin portion 1b is filled inside the bag portion 1a.

The variable pad 1 of this embodiment includes a main body portion 11 , rib portions 12 and rib portions 13 .

The body portion 11 is arranged between the tie plate 2 and the track pad 3, that is, between the tie plate 2 and the rail RA. The body portion 11 has a bag portion 11a that is part of the bag portion 1a and a resin portion 11b that is part of the resin portion 1b. The bag portion 11a is arranged between the tie plate 2 and the track pad 3, that is, between the tie plate 2 and the rail RA. The resin portion 11b is filled inside the bag portion 11a.

The resin portion 11b is formed by polymerizing and curing the liquid polymerizable composition injected into the bag portion 11a. As described above, the liquid polymerizable composition is injected into the interior of the bag portion 11a inserted between the tie plate 2 and the rail RA while the rail RA is raised to a position higher than the installation position. After that, the resin portion 11b is filled inside the bag portion 11a by polymerizing and curing the injected polymerizable composition while the rail RA is lowered to the installation position. That is, the resin portion 11b is formed by polymerizing and curing a liquid polymerizable composition while being sandwiched between the tie plate 2 and the rail RA with the track pad 3 interposed therebetween. With such a method, the sum of the thickness of the body portion 11 and the thickness of the track pad 3 becomes equal to the distance between the tie plate 2 and the bottom surface of the rail RA, so that the body portion 11 can be formed by the tie plate 2 and the rail. The thickness will be adjusted to fill the gap between RA.

The rib portion 12 is arranged on one side (first side) of the tie plate 2 and the track pad 3 in the X1 direction. The rib portion 12 has a bag portion 12a that is the other portion of the bag portion 1a and a resin portion 12b that is the other portion of the resin portion 1b. The bag body portion 12a is arranged on one side (first side) in the X1 direction relative to the tie plate 2 and the track pad 3. As shown in FIG. The interior of the bag body portion 12a communicates with the interior of the bag body portion 11a, and the bag body portion 12a is integrally formed with the bag body portion 11a. The resin portion 12b fills the inside of the bag portion 12a and is formed integrally with the resin portion 11b. When the track pad 3 is not inserted between the tie plate 2 and the rail RA, and only the variable pad 1 is inserted, the rib portion 12 is located on one side of the tie plate 2 in the X1 direction. (first side).

The resin portion 12b protrudes to one side (first side) in the X1 direction from the bag portion 11a, which is a portion of the bag portion 1a sandwiched between the tie plate 2 and the track pad 3 in plan view. It is formed by polymerizing and curing the liquid polymerizable composition injected into the bag body portion 12a.

As described above, the resin portion 11b is formed by polymerizing and curing a liquid polymerizable composition sandwiched between the tie plate 2 and the rail RA with the track pad 3 interposed therebetween. , the liquid polymerizable composition is polymerized and cured in a state not sandwiched between the tie plate 2 and the track pad 3 . Therefore, the thickness of the resin portion 12b in the Z1 direction is thicker than the thickness of the resin portion 11b in the Z1 direction. Moreover, the upper surface of the resin portion 12b is higher than the upper surface of the resin portion 11b, and the lower surface of the resin portion 12b is lower than the lower surface of the resin portion 11b. That is, the thickness of the rib portion 12 in the Z1 direction is thicker than the thickness of the main body portion 11 in the Z1 direction. Moreover, the upper surface of the rib portion 12 is higher than the upper surface of the main body portion 11 , and the lower surface of the rib portion 12 is lower than the lower surface of the main body portion 11 . When the track pad 3 is not inserted between the tie plate 2 and the rail RA and only the variable pad 1 is inserted, the upper surface of the rib portion 12 is at the same height as the upper surface of the main body portion 11. However, since the lower surface of the rib portion 12 is lower than the lower surface of the main body portion 11, the thickness of the rib portion 12 in the Z1 direction is greater than the thickness of the main body portion 11 in the Z1 direction.

The rib portion 13 is arranged on the other side (the side opposite to the first side) in the X1 direction relative to the tie plate 2 and the track pad 3 . The rib portion 13 has a bag body portion 13a that is still another portion of the bag body portion 1a, and a resin portion 13b that is still another portion of the resin portion 1b. The bag body portion 13a is arranged on the other side (the side opposite to the first side) in the X1 direction relative to the tie plate 2 and the track pad 3. As shown in FIG. The interior of the bag body portion 13a communicates with the interior of the bag body portion 11a, and the bag body portion 13a is integrally formed with the bag body portion 11a. The resin portion 13b fills the inside of the bag portion 13a and is formed integrally with the resin portion 11b. When the track pad 3 is not inserted between the tie plate 2 and the rail RA and only the variable pad 1 is inserted, the rib portion 13 is located on the other side of the tie plate 2 in the X1 direction. (the side opposite to the first side).

The resin portion 13b is located on the other side (opposite side to the first side) in the X1 direction from the bag portion 11a, which is a portion of the bag portion 1a sandwiched between the tie plate 2 and the track pad 3 in plan view. It is formed by polymerizing and curing the liquid polymerizable composition injected into the bag portion 13a, which is the protruding portion. Note that when the bag body portion 1a protrudes from the bag body portion 11a to one side in the X1 direction but does not protrude to the other side, the variable pad 1 includes the main body portion 11 and the rib portion 12. Although it is provided, there is a case where the rib portion 13 is not provided (the rib portion 12 and the rib portion 13 may be reversed).

As described above, the resin portion 11b is formed by polymerizing and curing a liquid polymerizable composition sandwiched between the tie plate 2 and the rail RA with the track pad 3 interposed therebetween. , the liquid polymerizable composition is polymerized and cured in a state not sandwiched between the tie plate 2 and the track pad 3 . Therefore, the thickness of the resin portion 13b in the Z1 direction is thicker than the thickness of the resin portion 11b in the Z1 direction. Moreover, the upper surface of the resin portion 13b is higher than the upper surface of the resin portion 11b, and the lower surface of the resin portion 13b is lower than the lower surface of the resin portion 11b. That is, the thickness of the rib portion 13 in the Z1 direction is thicker than the thickness of the main body portion 11 in the Z1 direction. Moreover, the upper surface of the rib portion 13 is higher than the upper surface of the main body portion 11 , and the lower surface of the rib portion 13 is lower than the lower surface of the main body portion 11 . When the track pad 3 is not inserted between the tie plate 2 and the rail RA, and only the variable pad 1 is inserted, the upper surface of the rib portion 13 is at the same height as the upper surface of the main body portion 11. However, since the bottom surface of the rib portion 13 is lower than the bottom surface of the main body portion 11, the thickness of the rib portion 13 in the Z1 direction is greater than the thickness of the main body portion 11 in the Z1 direction.

In the present embodiment, the resin portions 11b, 12b and 13b are all made of a so-called norbornene-based resin, which is a polymer 14 obtained by polymerizing a polymerizable composition 15 containing a monomer having a norbornene ring structure.

As described above, the variable pad 1 has the rib portion 12 or the rib portion 13, the resin portion 11b included in the body portion 11, the resin portion 12b included in the rib portion 12, and the resin portion included in the rib portion 13. Consider the case where 13b is made of, for example, a polyester-based resin which is a material conventionally used as the resin portion of the variable pad. In such a case, when the rail RA expands and contracts with changes in temperature, the rail RA moves in the extending direction of the rail RA. There is a risk of damage. Also, stress concentration on the rib portion 12 or the rib portion 13 during expansion and contraction of the rail RA occurs at a temperature, such as -20° C., which is significantly lower than about 20° C., for example. Therefore, at such a low temperature, the rib portion 12 or the rib portion 13 is damaged, and the variable pad 1 is easily damaged.

On the other hand, in the present embodiment, the resin portions 11b, 12b and 13b are all made of norbornene resin.

As will be described later with reference to FIGS. 4 to 6, the present inventors performed a cantilever bending test at −20° C. on a test piece made of norbornene-based resin. As a result of comparing the strength obtained by performing a cantilever bending test on a test piece made of resin at -20 ° C, the test piece made of norbornene resin is higher than the test piece made of polyester resin at -20 ° C. found to have strength.

Further, as will be described later with reference to FIGS. 7 to 9, the present inventors performed tensile tests on test pieces made of norbornene resin at room temperature (23° C.) and −20° C. As a result of comparing the strength obtained by performing a tensile test on a test piece made of polyester resin at the same temperature, the test piece made of norbornene resin at -20 ° C. Test made of polyester resin It was found that the strength is higher than that of a piece, and that the difference in strength at -20°C between the polyester-based resin and the norbornene-based resin is greater than the difference in strength at room temperature.

Therefore, since the resin portions 11b, 12b and 13b are all made of norbornene resin, even if stress concentrates on the rib portion 12 or the rib portion 13 when the rail RA expands and contracts at a low temperature of -20°C, the rib It has been found that it is possible to prevent the portions 12 and 13 from being damaged, that is, the variable pad 1 from being damaged. That is, it became clear that the variable pad 1 which is hard to be damaged even at low temperatures can be obtained.

Depending on the shapes of the variable pad 1, the tie plate 2, and the track pad 3, and the injection amount and pressure of the liquid polymerizable composition injected into the interior of the bag body portion 1a, the variable pad 1 may have rib portions 12 and rib portions. 13, the effect of preventing the variable pad 1 from being damaged when the resin portion 11b is made of a norbornene-based resin is more effective than when the resin portion 11b is made of a resin other than a norbornene-based resin. increases. Alternatively, even when the thickness of one of the resin portions 12b and 13b is substantially equal to the thickness of the resin portion 11b, the resin portion 11b is made of a norbornene-based resin, or the resin portion 11b is made of a resin other than a norbornene-based resin. Compared to , the effect of preventing damage to the variable pad 1 is enhanced.

In the technique described in Patent Document 1, the polymer is a copolymer of ethylene, an α-olefin, and a cyclic olefin (norbornene-based resin) using a so-called Ziegler catalyst of Group 4 such as titanium and zirconium. The cyclic olefin part is random and some of them have a structure that continues, which may be heterogeneous depending on the production method and scale. In the present embodiment, the polymer uses a metathesis catalyst. It is a (co)polymer of only the norbornene-based resin used, and has high uniformity because the vinylene portion and the cyclic olefin portion are alternately arranged. Further, in the technique described in Patent Document 1, the polymer is obtained by polymerization using a solution, whereas in the present embodiment, it is obtained by bulk polymerization.

The bag portion 1a, that is, the bag portions 11a, 12a and 13a, includes an outer surface layer (outer layer) 1c made of, for example, polyethylene terephthalate (PET), an intermediate layer 1d made of, for example, nylon, and, as described above, made of polyethylene. and the inner surface layer 1e can be used. At this time, the bag body portion 1a, that is, all of the bag body portions 11a, 12a and 13a include the inner surface layer (inner layer) 1e made of polyethylene. Preferably, the inner surface layer 1e and the resin portion 1b, that is, the inner surface layer 1e and the resin portions 11b, 12b and 13b are adhered to each other.

Consider a case where the resin portion 1b is made of a polyester-based resin. In such a case, when the polyester resin is cured, the inner surface layer 1e made of polyethylene and the resin portion 1b are not adhered to each other and integrated. Therefore, when the rail RA expands and contracts with changes in temperature, the rail RA expands, causing the bag body portion 1a and the resin portion 1b to shift from each other. When the bag body part 1a and the resin part 1b are displaced from each other, the bag body part 1a is easily damaged, or the resin part 1b is easily damaged, and the variable pad 1 is easily damaged.

As a method of preventing damage to the variable pad 1, a steel plate is provided on the upper surface of the track pad 3, that is, the contact surface of the track pad 3 that contacts the bottom surface of the rail RA, and metals having a small frictional force, namely the rail RA and the steel plate, are provided. A possible method is to release the rolling force when the rail RA rolls, that is, to prevent the rolling force from being transmitted to the track pad 3 by causing slippage between the rails RA and the rails RA.

However, when the bag body portion 1a includes the inner surface layer 1e made of polyethylene, the problem that the variable pad 1 is easily damaged has not been solved for the following reasons. That is, the resin portion 1b is formed by injecting a liquid polymerizable composition into the bag body portion 1a having a structure in which each of the three types of materials is laminated as described above, and polymerizing and curing the injected polymerizable composition. However, since the inner surface layer 1e of the bag body portion 1a is made of polyethylene, the bag body portion 1a and the resin portion 1b are not adhered to each other, and the bag body portion 1a and the resin portion 1b are integrated with each other. do not change Therefore, when the rail RA expands and contracts due to changes in temperature, slippage occurs between the inner surface layer 1e made of polyethylene and the resin portion 1b, so that the inherent expansion force is released. Therefore, slippage does not occur between the steel plate provided on the upper surface of the track pad 3 and the track pad 3, stress is concentrated on the resin portion 1b, and the rib portion 12 or the rib portion 13 is easily damaged. The variable pad 1 becomes easily damaged.

On the other hand, in the present embodiment, the resin portion 1b is made of norbornene-based resin. In such a case, since the amount of heat generated when the norbornene-based resin is cured is large, the inner surface layer 1e made of polyethylene and the resin portion 1b are welded together to be bonded and integrated. Therefore, even when the rail RA expands and contracts when the rail RA expands and contracts with a change in temperature, it is possible to prevent or suppress the displacement of the bag body portion 1a and the resin portion 1b from each other. Therefore, since the bag portion 1a and the resin portion 1b are less likely to be displaced from each other, damage to the bag portion 1a can be prevented or suppressed, and damage to the resin portion 1b can be prevented or suppressed. , the variable pad 1 can be prevented or suppressed from being damaged. Moreover, it is not necessary to provide a steel plate on the upper surface of the track pad 3, that is, the contact surface of the track pad 3 that contacts the bottom surface of the rail RA.

<Polymer and polymerizable composition>
Next, in the variable pad 1 of the present embodiment, the polymer filled inside the bag parts 11a, 12a and 13a, and the polymerizable composition as a raw material for forming the polymer, A suitable composition will be described.

As described above, in the present embodiment, the resin portions 11b, 12b, and 13b are all made of the polymer 14 obtained by polymerizing the polymerizable composition 15 containing a monomer having a norbornene ring structure, a so-called norbornene-based polymer. Made of resin.

The norbornene-based resin in the present specification means a polymer (polymer) obtained by polymerizing one type of monomer (monomer) having a norbornene ring structure, or a plurality of types of monomers (monomers) having a norbornene ring structure ) means a copolymer obtained by polymerizing. In other words, the norbornene-based resin in the present specification means a polymer obtained by polymerizing one type of norbornene-based monomer or a copolymer obtained by polymerizing a plurality of types of norbornene-based monomers. Accordingly, the polymer 14 is not particularly limited as long as it is a norbornene-based resin.

In this specification, in order to distinguish between the two, they are referred to as a first monomer and a second monomer for the sake of convenience, but both are norbornene-based monomers.

However, from the viewpoint of making the polymer 14 more excellent in quality stability, the polymerizable composition 15 containing a norbornene-based monomer and a metathesis polymerization catalyst is polymerized by bulk polymerization as the polymer 14 made of a norbornene-based resin. It is preferred to use cured polymers. Moreover, the polymerizable composition 15 is not particularly limited as long as it contains a norbornene-based monomer and a metathesis polymerization catalyst. However, it is preferable to use a liquid containing a norbornene-based monomer and a catalyst liquid, as described below, because thickening is easily suppressed.

Norbornene-based monomers, that is, monomers having a norbornene ring structure, bicyclics such as norbornene and norbornadiene; tricyclics such as dicyclopentadiene (cyclopentadiene dimer) and dihydrodicyclopentadiene; tetracyclododecene, etc. pentacyclic such as cyclopentadiene trimer; heptacyclic such as cyclopentadiene tetramer; These norbornene-based monomers include alkyl groups such as methyl group, ethyl group, propyl group and butyl group; alkenyl groups such as vinyl group; alkylidene groups such as ethylidene group; aryl groups such as phenyl group, tolyl group and naphthyl group; You may have a substituent such as Furthermore, these norbornene-based monomers may have polar groups such as carboxyl groups, alkoxycarbonyl groups, acyloxy groups, oxy groups, cyano groups, and halogen atoms.

Specific examples of such norbornene-based monomers include dicyclopentadiene (DCPD), tricyclopentadiene (TCPD), cyclopentadiene-methylcyclopentadiene co-dimer, 5-ethylidenenorbornene, norbornene, norbornadiene, 5-cyclohexenyl. norbornene, 1,4,5,8-dimethano-1,4,4a,5,6,7,8,8a-octahydronaphthalene, 1,4-methano-1,4,4a,5,6,7, 8,8a-octahydronaphthalene, 6-ethylidene-1,4,5,8-dimethano-1,4,4a,5,6,7,8,8a-octahydronaphthalene, 6-ethylidene-1,4- Methano-1,4,4a,5,6,7,8,8a-octahydronaphthalene, 1,4,5,8-dimethano-1,4,4a,5,6,7,8,8a-hexahydro naphthalene, ethylenebis(5-norbornene), and the like. The norbornene-based monomers may be used singly or in combination of two or more.

Among the above norbornene-based monomers, tricyclic, tetracyclic or pentacyclic norbornene-based monomers are preferred because they are easily available, have excellent reactivity, and have excellent heat resistance of the resulting norbornene-based resin. Cyclic norbornene-based monomers are more preferred, and dicyclopentadiene is particularly preferred.

Whether or not the polymer has a norbornene ring structure can be analyzed using, for example, nuclear magnetic resonance (NMR).

Preferably, the polymer 14 is polymerized, ie, copolymerized, of a first monomer having a norbornene ring structure and a second monomer having a norbornene ring structure and of a type different from the type of the first monomer. It consists of a copolymer. At this time, the polymerizable composition 15 that is polymerized and cured to become the polymer 14 contains a second monomer that has a norbornene ring structure and is of a type different from that of the first monomer. Here, the first monomer consists of dicyclopentadiene. The second monomer consists of one or more compounds represented by the general formula (1), preferably the group consisting of norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and tricyclopentadiene. Consisting of one or more selected from

In general formula (1), examples of hydrocarbon groups having 1 to 20 carbon atoms independently represented by R ¹ to R ⁴ include methyl, ethyl and propyl groups having 1 to 20 carbon atoms. aryl groups having 6 to 20 carbon atoms such as phenyl group and 2-naphthyl group; and cycloalkyl groups having 3 to 20 carbon atoms such as cyclopropyl group, cyclopentyl group and cyclohexyl group; and the like. Examples of the alkylidene group formed jointly by R ¹ and R ² or R ³ and R ⁴ include a methylidene group (=CH ₂ ), an ethylidene group (=CH--CH ₃ ), and a propylidene group (=CH--C ₂ H ₅ ) and the like. Examples of ring structures formed by R ¹ and/or R ² and R ³ and/or R ⁴ include cyclopentane ring, cyclopentene ring, cyclohexane ring and cyclohexene ring.

When the polymer 14 is polymerized by combining the above-described type of the first monomer and the above-described type of the second monomer, compared to the case where the polymer 14 is polymerized by combining types of monomers other than the combination , the amount of shrinkage when the polymerizable composition 15 is cured during manufacture of the variable pad 1 is reduced. Therefore, after the polymerizable composition 15 is cured, the stress applied to the variable pad 1 or the resin portion 1b made of the polymer 14 is reduced due to the curing, and after the polymerizable composition 15 is cured by polymerization, the polymer It is possible to prevent or suppress the generation of voids or cracks in the resin portion 1b formed of 14, that is, the cracking of the resin portion 1b. In addition, when the variable pad 1 is used at a low temperature of about −20° C., the stress applied to the variable pad 1 or the resin portion 1b made of the polymer 14 when the variable pad 1 is cooled becomes small. The effect of preventing or suppressing the generation of voids or cracks in the resin portion 1b made of the polymer 14, that is, the cracking of the resin portion 1b, during use of 1 becomes greater.

More preferably, when the total of the content of the first monomer in the polymerizable composition 15 and the content of the second monomer in the polymerizable composition 15 used as the raw material of the polymer 14 is 100 parts by mass, polymerization The content of the second monomer in the sexual composition 15 is 4 parts by mass or more. That is, the content of the first monomer in the polymerizable composition 15 is 96 parts by mass or less.

When the content of the second monomer in the polymerizable composition 15 is 4 parts by mass or more, compared to the case where the content of the second monomer in the polymerizable composition 15 is less than 4 parts by mass, during the production of the variable pad 1, polymerization When the adhesive composition 15 cures, excessive cross-linking is suppressed and the amount of shrinkage is smaller. Therefore, after the polymerizable composition 15 is polymerized and cured, the stress applied to the variable pad 1 or the resin portion 1b made of the polymer 14 due to the curing becomes smaller. The generation of voids or cracks in the resin portion 1b formed by the coalescence 14, that is, the cracking of the resin portion 1b can be further prevented or suppressed. In addition, when the variable pad 1 is used at a low temperature of about -20°C, the stress applied to the variable pad 1 or the resin portion 1b made of the polymer 14 becomes smaller when the variable pad 1 is cooled. When the pad 1 is used at a low temperature of about −20° C., the effect of preventing or suppressing the occurrence of cracks in the resin portion 1b made of the polymer 14, that is, the breakage of the resin portion 1b, becomes even greater.

However, preferably, when the total of the content of the first monomer in the polymerizable composition 15 and the content of the second monomer in the polymerizable composition 15 is 100 parts by mass, the second monomer in the polymerizable composition 15 is 50 parts by mass or less. That is, the content of the first monomer in the polymerizable composition 15 is 50 parts by mass or more. More preferably, the content of the second monomer is 5 parts by mass or more and 45 parts by mass or less, and even more preferably, the content of the second monomer is 6 parts by mass or more and 40 parts by mass or less.

When the content of the second monomer in the polymerizable composition 15 is 50 parts by mass or less, compared to when the content of the second monomer in the polymerizable composition 15 exceeds 50 parts by mass, during the production of the variable pad 1, polymerization When the chemical composition 15 is polymerized and cured, cross-linking provides a more preferable polymerized and cured product that is stable in terms of chemical structure.

Regarding the fact that the polymer 14 is obtained by polymerizing the first monomer and the second monomer, and the content of the first monomer and the second monomer in the polymer 14, the polymer 14 is, for example, It can be determined by performing analysis by NMR.

As previously mentioned, the polymerizable composition 15 preferably contains a catalyst component of a metathesis polymerization catalyst system. The metathesis polymerization catalyst is not particularly limited as long as it can carry out ring-opening polymerization of norbornene-based monomers, and known catalysts can be used.

The polymerization catalyst component is preferably a metathesis polymerization catalyst. The metathesis polymerization catalyst is not particularly limited as long as it is a catalyst capable of ring-opening polymerization of norbornene-based monomers. A metathesis polymerization catalyst is a complex composed of a plurality of ions, atoms, polyatomic ions and/or compounds bound to a transition metal atom as a central atom. As the transition metal atoms, atoms of Groups 5, 6 and 8 (long period periodic table, hereinafter the same) are used. Atoms in each group are not particularly limited, but Group 5 atoms include, for example, tantalum, Group 6 atoms include, for example, molybdenum and tungsten, and Group 8 atoms include, for example, ruthenium. and osmium.

Examples of metathesis polymerization catalysts having group 6 tungsten or molybdenum as a central metal include metal halides such as tungsten hexachloride; metal oxyhalides such as tungsten chloride oxide; metal oxides such as tungsten oxide; Organometallic ammonium salts such as molybdate and tri(tridecyl)ammonium molybdate can be used. Among these, organic molybdate ammonium salts are preferred. When using these metathesis polymerization catalysts, it is preferable to use an organoaluminum compound or an organotin compound as an activator (co-catalyst) in combination for the purpose of controlling the polymerization activity.

In the present invention, it is also preferable to use a metal carbene complex having a group 5, 6 or 8 metal atom as the central metal as the metathesis polymerization catalyst. Among metal carbene complexes, group 8 ruthenium and osmium carbene complexes are preferred, and ruthenium carbene complexes are particularly preferred. This is because the activity of the catalyst during bulk polymerization is excellent, resulting in excellent productivity. Among the ruthenium carbene complexes, ruthenium carbene complexes in which at least two carbene carbons are bonded to a ruthenium metal atom and at least one of the carbene carbons is bonded to a heteroatom-containing group are particularly preferred. Here, "carbene compound" is a generic term for compounds having a methylene free radical, and refers to compounds having an uncharged divalent carbon atom (carbene carbon) represented by (>C:). Since the ruthenium carbene complex is excellent in catalytic activity during bulk ring-opening polymerization, the obtained polymer has little odor derived from unreacted monomers, and a high-quality polymer can be obtained with good productivity. In addition, it is relatively stable against oxygen and moisture in the air, and is resistant to deactivation, so it can be used in the atmosphere. Only one type of metathesis polymerization catalyst may be used, or a plurality of types may be used in combination.

The content of the metathesis polymerization catalyst is preferably 0.005 millimoles or more, more preferably 0.01 to 50 millimoles, still more preferably 0.015 to 20 millimoles, per 1 mol of the total monomers used in the reaction. be.

Other optional components include activators, activity modifiers, elastomers, antioxidants, and the like.

The activator is a compound that acts as a co-catalyst for the metathesis polymerization catalyst described above and improves the polymerization activity of the catalyst. Examples of the activator include alkylaluminum halides such as ethylaluminum dichloride and diethylaluminum chloride; alkoxyalkylaluminum halides obtained by substituting part of the alkyl groups of these alkylaluminum halides with alkoxy groups; and organic tin compounds. . The amount of the activator to be used is not particularly limited, but is generally preferably 0.1 to 100 mol, more preferably 1 to 10 mol, per 1 mol of the total metathesis polymerization catalyst used in the polymerizable composition.

The activity control agent is used to prevent polymerization from starting during injection when a polymerizable composition is prepared by mixing two or more reaction stock solutions and injected into a mold to initiate polymerization. .

When a compound of a transition metal of group 5 or 6 of the periodic table is used as the metathesis polymerization catalyst, examples of the activity regulator include compounds having a reducing action on the metathesis polymerization catalyst, alcohols, haloalcohols, Esters, ethers, nitriles and the like can be used. Among them, alcohols and haloalcohols are preferred, and haloalcohols are more preferred.

Specific examples of alcohols include n-propanol, n-butanol, n-hexanol, 2-butanol, isobutyl alcohol, isopropyl alcohol, t-butyl alcohol and the like. Specific examples of haloalcohols include 1,3-dichloro-2-propanol, 2-chloroethanol, 1-chlorobutanol and the like.

As a metathesis polymerization catalyst, especially when using a ruthenium carbene complex, a Lewis base compound can be mentioned as an activity regulator. Lewis base compounds containing phosphorus atoms such as tricyclopentylphosphine, tricyclohexylphosphine, triphenylphosphine, triphenylphosphite, n-butylphosphine; n-butylamine, pyridine, 4-vinylpyridine, acetonitrile, Lewis base compounds containing a nitrogen atom such as ethylenediamine, N-benzylidenemethylamine, pyrazine, piperidine, imidazole, and the like. In addition, alkenyl-substituted norbornenes such as vinylnorbornene, propenylnorbornene and isopropenylnorbornene function as monomers as well as activity modifiers. The amount of these activity regulators to be used may be appropriately adjusted depending on the compound used.

Examples of elastomers include natural rubber, polybutadiene, polyisoprene, styrene-butadiene copolymer (SBR), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), and ethylene. -Propylene-diene terpolymer (EPDM), ethylene-vinyl acetate copolymer (EVA) and hydrides thereof. By dissolving the elastomer in the polymerizable composition and using it, the viscosity can be adjusted. Also, by adding an elastomer, the impact resistance of the resulting polymer can be improved. The amount of elastomer used is preferably 0.5 to 20 parts by mass, more preferably 2 to 10 parts by mass, based on 100 parts by mass of all monomers in the polymerizable composition.

Examples of antioxidants include phenol-based, phosphorus-based, and amine-based antioxidants for various plastics and rubbers.

In addition, the polymerizable composition may contain a filler as an optional component, provided that the viscosity of the polymerizable composition is within the suitable range described below.

The temperature of the reaction stock solution before supply is preferably 10 to 60° C., and the viscosity of the reaction stock solution is usually about 5 to 3,000 mPa·s, preferably about 50 to 1,000 mPa·s at 30° C., for example. be.

Hereinafter, this embodiment will be described in further detail based on examples. In addition, the present invention is not limited to the following examples.

[Preparation of polymerizable composition]
(Production example 1)
In Production Example 1, a first monomer consisting of dicyclopentadiene and a metathesis polymerization consisting of benzylidene{1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene}dichloro(tricyclohexylphosphine)ruthenium A polymerizable composition containing a catalyst was provided. The resulting polymerizable composition was maintained at 20°C. The amount of metathesis polymerization catalyst used was 0.055 millimoles per 1 mole of total monomers used. Moreover, the viscosity of the polymerizable composition at 25° C. was 10 mPa·s or less as measured by a Brookfield viscometer.

(Production example 2)
In Production Example 2, a polymerizable composition containing a first monomer made of dicyclopentadiene, a second monomer made of tricyclopentadiene, a metathesis polymerization catalyst made of tridodecylammonium molybdate, and alkylaluminum as a co-catalyst was prepared. bottom. Further, styrene-butadiene rubber was dissolved in the polymerizable composition so that the viscosity was 250 mPa·s as measured by a Brookfield viscometer at 25°C. The polymerizable composition was maintained at 20°C. When the sum of the content of the first monomer in the polymerizable composition and the content of the second monomer in the polymerizable composition is 100 parts by mass, the content of the second monomer in the polymerizable composition is 7 parts by mass. there were. The amount of metathesis polymerization catalyst used was 0.8 millimoles per 1 mol of all monomers used.

[Evaluation of polymerization curing of polymerizable composition]
Next, the polymerizable compositions of Production Examples 1 and 2 are injected into the mold under an environment of 20° C., left to stand until the resin does not flow (precuring), and then heated at a temperature of 80° C. for 1 hour. The polymerization and curing of the polymerizable compositions of Production Examples 1 and 2 were visually evaluated by heat-treating under the conditions of the heating time of . The polymerizable composition of Production Example 2 was injected in an environment of 20° C. while mixing just before the half-split mold was heated to 70° C. on one side and 40° C. on the other side. The polymerizable composition was sufficiently cured without heat treatment when the polymerization and curing was visually evaluated.

As a result, it was confirmed that both the polymerizable compositions of Production Examples 1 and 2 were easily polymerized and cured in a state in which the upper surface was flattened. Therefore, it was confirmed that both the polymerizable compositions of Production Example 1 and Production Example 2 could be easily injected into the interior of the bag and polymerized and cured easily.

Although detailed description is omitted, in place of tricyclopentadiene in Production Example 2, norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and other compounds represented by the general formula (1) are used. Similar results were obtained when using Therefore, when the polymerizable composition contains a first monomer made of dicyclopentadiene and a second monomer, and the second monomer is at least one compound represented by the general formula (1) As described above, preferably when the second monomer consists of one or more selected from the group consisting of norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and tricyclopentadiene, the second monomer is of any other kind. It has become clear that voids are less likely to occur in the resin composition formed by polymerization and curing, and a high-quality resin composition can be formed, as compared to the case of using a monomer.

[Cantilever bending test]
Below, test pieces of Example 1 and Comparative Examples 1 and 2 were prepared, and the prepared test pieces were subjected to a cantilever bending test using a cantilever bending test jig provided in a material testing machine. did

(Example 1 and Comparative Examples 1 and 2)
Prepare a polymerizable composition containing a first monomer consisting of dicyclopentadiene, a second monomer consisting of tricyclopentadiene, and the metathesis polymerization catalyst described in Production Example 2, that is, the polymerizable composition according to Production Example 2. bottom. The resulting polymerizable composition was maintained at 20°C. Here, when the total of the content of the first monomer in the polymerizable composition and the content of the second monomer in the polymerizable composition is 100 parts by mass, the content of the second monomer in the polymerizable composition is 7. was parts by mass. The viscosity of the polymerizable composition at 25° C. was 250 mPa·s as measured by a Brookfield viscometer. The amount of metathesis polymerization catalyst used was 0.8 millimoles per 1 mol of all monomers used.

The polymerizable composition thus obtained is injected into a mold in an environment of 20° C. and allowed to stand until the resin flow disappears (precuring), followed by a heating temperature of 80° C. and a heating time of 1 hour. By heat-treating and polymerizing and curing under the conditions of, it has a strip shape with a width of 10 ± 0.5 mm, a thickness of 4 ± 0.5 mm and a length of 80 ± 0.5 mm, and is made of norbornene resin. A test piece of the polymer was prepared.

On the other hand, a test piece of the polymer of Comparative Example 1 made of polyester resin was prepared in the same manner as the method of preparing the test piece of the polymer of Example 1, except that the polymerizable composition was replaced with a polyester resin. bottom.

Further, a polyester resin different from Comparative Example 1 was performed in the same manner as in the method for producing a test piece of the polymer of Example 1 except that the polymerizable composition was replaced with a polyester resin different from Comparative Example 1. A test piece of the polymer of Comparative Example 2 was prepared.

FIG. 4 is a side view showing an arrangement for performing a cantilever bending test on a test piece using a cantilever bending test jig. FIG. 5 is a plan view showing an arrangement when performing a cantilever bending test on a test piece using a cantilever bending test jig.

As shown in FIGS. 4 and 5, in a state in which the test piece TE1 is held by the cantilever bending test jig 21, the length direction of the test piece TE1 is the X2 direction, and the width direction of the test piece TE1 is the Y2 direction. , and the thickness direction of the test piece TE1 was the Z2 direction.

As shown in FIGS. 4 and 5, the material testing machine MA1 for conducting the cantilever bending test was equipped with a cantilever bending test jig 21 and a constant temperature bath 22 . The cantilever bending test jig 21 had a holding portion 23 and a pressing portion 24 . The holding portion 23 includes a main body 25 provided with a stopper 25 a , a fixing plate 26 , and two screws 27 for fixing the fixing plate 26 to the main body 25 . One side of the test piece TE1 in the X2 direction contacts the stopper 25a, and the test piece TE1 is sandwiched between the main body 25 and the fixing plate 26 from above and below. By doing so, the test piece TE1 was held by the holding portion 23 .

The pressing portion 24 is movable in the Z2 direction and is provided so that the load can be measured by a load cell (not shown) provided in the material testing machine MA1. A downward load LD1 in the Z2 direction was able to be applied to the test piece TE1 at a position PS2 separated from the position PS1 on the opposite side by a distance DS1 in the X2 direction. At this time, the position PS1 was the position where the end EP1 of the restrained portion PA1 of the test piece TE1 and the end EP1 of the unrestrained portion PA2 of the test piece TE1 were located. Further, the position PS2 is the position where the portion PA3 of the portion PA2 to which the load in the thickness direction of the portion PA1 is applied is located. Note that the distance DS1 was 11 mm. A corner portion 25b at the end of the main body 25 opposite to the stopper 25a side is processed to have a curvature of 4 mm in radius, and a tip portion 24a of the pressing portion 24 is formed into a semi-cylindrical shape to have a curvature of 5 mm in radius. had been processed.

As shown in FIGS. 4 and 5, for each test piece of Comparative Example 1, Comparative Example 2, and Example 1, the test piece TE1 was held by the holding portion 23 and fixed in a cantilever shape, and the position PS2 In the above, a cantilever bending test is performed by pressing the portion PA3 with the pressing portion 24 and applying a load LD1 to the portion PA3 to deform the portion PA3 downward. It was measured. The deformation speed, which is the speed at which the load LD1 is applied to the portion PA3 to deform it, was set to 5 mm/min. Considering that the variable pad 1 is actually used in a cold region, the temperature of the test environment, that is, the temperature inside the constant temperature bath 22 was -20±2°C.

FIG. 6 is a graph showing the amount of deformation when the test piece breaks, obtained by performing a cantilever bending test on each test piece of Comparative Example 1, Comparative Example 2, and Example 1. FIG. The vertical axis in FIG. 6 indicates the amount of deformation when the test piece breaks.

6 shows the amount of deformation when the test piece TE1 is actually broken in Comparative Examples 1 and 2, but in Example 1, the height HG1 of the main body 25 is 10 mm and 22 mm. However, even if the upper limit of the allowable range of deformation amount is set to either 10 mm or 22 mm, the test piece TE1 does not break and contacts the part below the main body 25, so that it cannot be deformed any more. could not.

As shown in FIG. 6, both the test pieces of Comparative Examples 1 and 2 made of polyester-based resin were broken with a deformation amount of about 4 to 6 mm. On the other hand, the test piece of Example 1 made of norbornene-based resin did not break when the upper limit of the allowable range of deformation was set to 10 mm or 22 mm.

That is, a test piece TE1 composed of a polymer 14 (see FIG. 3) obtained by polymerizing a polymerizable composition 15 (see FIG. 3) containing a monomer having a norbornene ring structure and having a width of 10 mm, a thickness of 4 mm and a length of 80 mm was prepared. The prepared test piece TE1 was placed at a position PS1 where the end EP1 of the restrained portion PA1 of the test piece TE1 and the end EP1 on the side of the unrestrained portion PA2 of the test piece TE1 is positioned. to the position PS2 where the load LD1 in the thickness direction of the portion PA1 of the portion PA2 is 11 mm. When a cantilever bending test was performed in which a load was applied and deformed to the portion PA3 under the conditions of a deformation rate of 5 mm / min and a temperature of -20 ° C., the test piece TE1 was , the deformation of the portion PA3 in the thickness direction of the portion PA1 is 10 mm or 22 mm, no breakage occurs.

In other words, when the cantilever bending test is performed under the conditions, the amount of deformation of the portion PA3 in the thickness direction of the portion PA1 when the test piece TE1 is broken is 10 mm or more. When the cantilever bending test was performed, it was found that the amount of deformation in the thickness direction of the portion PA3 of the portion PA3 that can be deformed without breaking the test piece TE1 was 10 mm or more. In addition, since the test piece TE1 did not break even when the upper limit of the allowable range of the deformation amount was set to 22 m, the deformation amount in the thickness direction of the portion PA3 that can be deformed without breaking the test piece TE1 was 10 m. ~22 mm.

As a result, in the cantilever bending test, the present inventors found that a test piece made of norbornene-based resin has a higher strength than a test piece made of polyester-based resin at -20 ° C., and that polyester-based resin and norbornene-based It was found that there is a large difference in strength at -20° C. with the resin.

Further, when the rail RA moves in the X1 direction with respect to the variable pad 1 shown in FIG. In the cantilever bending test shown in FIGS. 4 and 5, a downward load LD1 in the Z2 direction is applied while the test piece TE1 is fixed in a cantilever shape along the X2 direction, which is the length direction. corresponds to the case Therefore, in the cantilever bending test shown in FIGS. 4 and 5, the fact that the test piece made of norbornene-based resin at -20° C. has a higher strength than the test piece made of polyester-based resin indicates that the rail RA at -20° C. This means that the variable pad 1 is less likely to break even if the stress FR1 concentrates on the rib portion 12 due to the expansion.

Therefore, in the cantilever bending test, stress was concentrated on the ribs 12 and 13 when the rail RA expanded and contracted at a low temperature of -20°C because the resin portions 11b, 12b and 13b were all made of norbornene resin. Even in such a case, the rib portions 12 and 13 can be prevented from being damaged, that is, the variable pad 1 can be prevented from being damaged, and the variable pad 1 which is resistant to damage even at low temperatures can be obtained.

Although detailed description is omitted, as the second monomer, instead of tricyclopentadiene (Production Example 2), norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and other monomers of the above general formula Also when the compound represented by (1) was used, the same results as in Example 1 were obtained in the cantilever bending test. Similar results were also obtained when the polymerizable composition prepared according to Production Example 1 was used in place of Production Example 2. Furthermore, with respect to the various test pieces described above, similar results were obtained in the cantilever bending test not only when test pieces prepared separately from the variable pad 1 were used, but also when test pieces cut from the variable pad 1 and processed were used. Got.

[Tensile test]
Next, test pieces of Example 2 and Comparative Examples 3 and 4 were produced, and a tensile test was performed on the produced test pieces using a tensile test jig provided in a material testing machine.

(Example 2 and Comparative Examples 3 and 4)
JIS K7161-2 "Plastics-Determination of tensile properties-Part 2: Test conditions for molded, extruded and cast plastics" Type 1B A test piece of the polymer of Example 2 having a dumbbell shape and made of the same norbornene-based resin as the test piece of Example 1 (manufacturing example 2) was prepared. The dumbbell shape of this JIS K7161-2 "Plastics-Determination of tensile properties-Part 2: Test conditions for molded, extruded and cast plastics" 1B type was as follows.
Total length: 150mm
Length of narrow parallel part: 60.0±0.5mm
Radius: 60±0.5mm
Distance to wide parallel part: 108±1.6mm
Edge width: 20.0±0.2mm
Width of narrow part: 10.0±0.2mm
Thickness: 4.0±0.2mm
Gauge distance: 50.0±0.5mm
Distance between grips: 115±1mm

On the other hand, a polymer of Comparative Example 3 made of the same polyester resin as the test piece of Comparative Example 1 in the same manner as in the method of preparing a test piece of the polymer of Example 2 except that the polymerizable composition was changed. A test piece was prepared.

Further, a polymer of Comparative Example 4 made of the same polyester resin as the test piece of Comparative Example 2 in the same manner as in the method of preparing the test piece of the polymer of Example 2 except that the polymerizable composition was changed. A test piece was prepared.

FIG. 7 is a front view showing an arrangement for performing a tensile test on a test piece using a tensile test jig. FIG. 8 is a side view showing an arrangement when performing a tensile test on a test piece using a tensile test jig.

As shown in FIGS. 7 and 8, with the test piece TE2 held by the tensile test jig 31, the length direction of the test piece TE2 is the X3 direction, the width direction of the test piece TE2 is the Y3 direction, The thickness direction of the test piece TE2 was taken as the Z3 direction.

As shown in FIGS. 7 and 8, the material testing machine MA2 used for the tensile test was equipped with a tensile test jig 31 and a constant temperature bath 32 . The tensile test jig 31 had an upper gripper 33 and a lower gripper 34 . The upper gripper 33 includes a main body 35 having a cut 35a formed thereon and two bolts 36 for clamping and fixing two holding plates 35b of the main body 35 that face each other across the cut 35a. The lower gripper 34 includes two holding plates 37 and a fixing member (not shown) that sandwiches and fixes the two holding plates 37 .

The upper gripper 33 grips the end EP2 of the test piece TE2 in the X3 direction as a wide parallel portion, and the lower end EP3 as the lower wide parallel portion of the test piece TE2 in the X3 direction is gripped. The test piece TE2 was held by the upper gripper 33 and the lower gripper 34 while being gripped by the tool 34 . In other words, the upper (second side) end EP2 of the test piece TE2 in the length direction of the test piece TE2 is held by the upper gripper 33 as an upper holding portion, and the test piece TE2 of the test piece TE2 The lower (opposite to the second side) end EP3 in the length direction is held by a lower grip 34 as a lower holding portion. One of the upper gripper 33 and the lower gripper 34 is movable relative to the other in the X3 direction, and at least one of them is provided so that the load can be measured by a load cell (not shown) provided in the material testing machine MA2. It was possible to stretch the test piece TE2 by pulling it in the X3 direction. Incidentally, the diameter of the two bolts 36 was 8 mm.

As shown in FIGS. 7 and 8, for each of the test pieces of Comparative Examples 3, 4, and 2, the test piece TE2 was held by the upper gripper 33 and the lower gripper 34, and the test piece TE2 was held. The upper gripper 33 is moved relative to the lower gripper 34 so that the test piece TE2 extends in the length direction of the test piece TE2. The amount of elongation when the was broken was measured. The tensile speed, which is the speed at which the upper gripper 33 is moved relative to the lower gripper 34 so that the test piece TE2 extends in the longitudinal direction of the test piece TE2, was set to 20 mm/min. Considering that the variable pad 1 is actually used in a cold region, the temperature of the test environment, ie, the temperature inside the constant temperature bath 32, was set to -20±2°C.

Table 1 shows the amount of elongation at break of the test piece, which was obtained by performing a tensile test on each test piece of Comparative Examples 3, 4 and 2. Table 1 also shows the maximum stress and energy when the test piece breaks.

For each of Comparative Example 3, Comparative Example 4 and Example 2, three specimens of the same type were used. In Table 1, the three test pieces of Comparative Example 3 are indicated as Comparative Example 3-1, Comparative Example 3-2, and Comparative Example 3-3, and the three test pieces of Comparative Example 4 are indicated as Comparative Example 4-1. , Comparative Examples 4-2 and 4-3, and the three test pieces of Example 2 are indicated as Examples 2-1, 2-2 and 2-3.

FIG. 9 is a graph showing the amount of elongation when the test piece breaks, obtained by performing a tensile test on each test piece of Comparative Examples 3, 4 and 2. FIG. The vertical axis in FIG. 9 indicates the average value of the elongation when each of the three test pieces of the same kind was broken.

As shown in FIG. 9 and Table 1, for the test piece of Comparative Example 3 made of polyester resin, the elongation amount when the test piece broke was 7 to 8 mm for the three test pieces of the same type. The average value between strips was 7 mm. In addition, for the test piece of Comparative Example 4 made of polyester resin, the elongation amount when the test piece was broken was 10 to 13 mm for three test pieces of the same type, and the average value among the three test pieces was was 12 mm. On the other hand, for the test pieces of Example 2 made of norbornene resin, the elongation amount when the test piece broke was 23 to 47 mm for three test pieces of the same type, and the average value among the three test pieces was was 33 mm.

That is, it consists of a polymer 14 (see FIG. 3) obtained by polymerizing a polymerizable composition 15 (see FIG. 3) containing a monomer having a norbornene ring structure, and conforms to JIS K 7161-2 "Plastics-Determination of tensile properties-Second Part: Molding, Extrusion Molding, and Casting Plastic Test Conditions A test piece TE2 having a dumbbell shape of 1B type was prepared, and the upper side of the prepared test piece TE2 in the length direction (X3 direction) of the test piece TE2 The (second side) end EP2 is held by the upper gripper 33 as an upper holding part, and the lower (opposite to the second side) end of the test piece TE2 in the length direction (X3 direction) It is the speed at which the upper gripper 33 is moved relative to the lower gripper 34 so that the part EP3 is held by the lower gripper 34 as the lower holding part and the test piece TE2 extends in the length direction (X3 direction). A tensile test was performed by stretching the test piece TE2 in the length direction (X3 direction) under conditions of a tensile speed of 20 mm/min and a temperature of -20°C. When a tensile test was performed under these conditions, it was found that the amount of elongation of the test piece TE2 when the test piece TE2 was broken was 23 mm or more.

In addition, for the test piece of Comparative Example 3 made of polyester resin, the maximum stress when the test piece broke was 52 to 57 MPa for the three test pieces of the same type, and the average value among the three test pieces was It was 55 MPa. In addition, for the test piece of Comparative Example 4 made of polyester resin, the maximum stress when the test piece broke was 46 to 58 MPa for three test pieces of the same type, and the average value among the three test pieces was It was 53 MPa. On the other hand, for the test piece of Example 2 made of norbornene resin, the maximum stress when the test piece broke was 68 to 69 MPa for three test pieces of the same type, and the average value among the three test pieces was It was 68 MPa.

Thus, since the maximum stress of Example 2 is larger than the maximum stress of Comparative Examples 3 and 4, at a low temperature of -20 ° C., the elastic modulus of norbornene-based resin is higher than that of polyester-based It was found that the elastic modulus of the norbornene-based resin is higher than the strength of the polyester-based resin.

In addition, for the test piece of Comparative Example 3 made of polyester resin, the energy when the test piece broke was 6 to 7 J for three test pieces of the same type, and the average value among the three test pieces was 7 J. Met. In addition, for the test piece of Comparative Example 4 made of polyester resin, the energy when the test piece broke was 9 to 17 J for the three test pieces of the same type, and the average value among the three test pieces was 14 J. Met. On the other hand, for the test pieces of Example 2 made of norbornene-based resin, the energy when the test piece broke was 38 to 88 J for three test pieces of the same type, and the average value among the three test pieces was 59 J. Met.

Thus, since the energy at breakage of Example 2 is larger than the energy at breakage of either Comparative Example 3 or Comparative Example 4, at a low temperature of -20 ° C., norbornene-based resin It has been clarified that the energy at breakage is higher than the energy at breakage of the polyester-based resin.

That is, of the manufactured test piece TE2, the upper (third side) end EP2 in the length direction (X3 direction) of the test piece TE2 is held by the upper gripper 33 as an upper holding portion, and the test piece TE2 is held. The lower gripper 34 as a lower holding part holds the end EP3 on the lower side (the side opposite to the third side) in the length direction (X3 direction), and the test piece TE2 is held in the length direction (X3 direction). ) at a tensile speed of 20 mm/min and a temperature of −20° C., the test piece TE2 is stretched in the longitudinal direction (X3 direction) was performed. When a tensile test was performed under these conditions, it was found that the energy at breakage of the test piece TE2 was 38 J or more.

(Example 3 and Comparative Examples 5 and 6)
In addition, the test piece of Comparative Example 5 made of the same polyester resin as the test piece of Comparative Example 3, the test piece of Comparative Example 6 made of the same polyester resin as the test piece of Comparative Example 4, and the test piece of Example 2 A test piece of Example 3 made of the same type of norbornene resin as the test piece was prepared, and the tensile test was performed under the same conditions except that the temperature was changed to -20 ° C. and 23 ° C. went. Table 2 shows the amount of elongation at break of the test piece, which was obtained by performing a tensile test on each of the test pieces of Comparative Examples 5, 6 and Example 3. Table 2 also shows the maximum stress and energy when the test piece broke.

For each of Comparative Example 5, Comparative Example 6 and Example 3, three specimens of the same type were used. In Table 2, the three test pieces of Comparative Example 5 are indicated as Comparative Example 5-1, Comparative Example 5-2 and Comparative Example 5-3, and the three test pieces of Comparative Example 6 are indicated as Comparative Example 6-1 , Comparative Examples 6-2 and 6-3, and the three test pieces of Example 3 are indicated as Examples 3-1, 3-2 and 3-3.

Although graphical representation is omitted, as shown in Table 2, for the test piece of Comparative Example 5 made of polyester resin, the elongation amount when the test piece broke was 9 to 11 mm for three test pieces of the same type. and the average value among the three test pieces was 10 mm. In addition, for the test piece of Comparative Example 6 made of polyester resin, the elongation amount when the test piece broke was 38 to 48 mm for three test pieces of the same type, and the average value among the three test pieces was was 44 mm. In addition, for the test piece of Example 3 made of norbornene resin, the elongation amount when the test piece broke was 92 to 100 mm for three test pieces of the same type, and the average value among the three test pieces was was 95 mm.

However, for the test piece of Comparative Example 5 made of polyester resin, the maximum stress when the test piece broke was 53 to 55 MPa for the three test pieces of the same type, and the average value among the three test pieces was It was 54 MPa. In addition, for the test piece of Comparative Example 6 made of polyester resin, the maximum stress when the test piece broke was 26 to 27 MPa for three test pieces of the same type, and the average value among the three test pieces was It was 27 MPa. In addition, for the test pieces of Example 3 made of norbornene-based resin, the maximum stress when the test piece broke was 51 to 55 MPa for three test pieces of the same type, and the average value among the three test pieces was It was 53 MPa.

In addition, for the test piece of Comparative Example 5 made of polyester resin, the energy when the test piece broke was 9 to 11 J for three test pieces of the same type, and the average value among the three test pieces was 10 J. Met. In addition, for the test piece of Comparative Example 6 made of polyester resin, the energy when the test piece broke was 32 to 39 J for the three test pieces of the same type, and the average value among the three test pieces was 36 J. Met. On the other hand, for the test piece of Example 3 made of norbornene-based resin, the energy when the test piece broke was 141 to 157 J for three test pieces of the same type, and the average value among the three test pieces was 147 J. Met.

That is, although the energy at breakage of Example 3 is larger than the energy at breakage of Comparative Example 5, the maximum stress at breakage between Comparative Example 5 and Example 3 is substantially the same, so 23 At room temperature of °C, the elongation amount and energy at breakage of the test piece increased because the elastic modulus of the norbornene-based resin was not so high, rather than because the strength of the norbornene-based resin was high.

Summarizing the above results, in the tensile test, the present inventors found that the test piece made of norbornene resin at -20 ° C. has a higher strength than the test piece made of polyester resin, and that the polyester resin and It was found that the difference in strength at −20° C. with the norbornene-based resin was greater than the difference in strength at room temperature.

The stress FR1 is concentrated on the rib portion 12 due to the rail RA moving in the X1 direction relative to the variable pad 1 shown in FIG. 3, and the rib portion 12 is pressed in the X1 direction. This corresponds to the case where the test piece TE2 is stretched in the X3 direction while being held by the upper gripper 33 and the lower gripper 34 along the X3 direction, which is the length direction, in the tensile test shown in FIG. Therefore, in the tensile tests shown in FIGS. 7 and 8, the fact that the test piece made of norbornene-based resin at -20°C has a higher strength than the test piece made of polyester-based resin indicates that the rail RA progresses at -20°C. This means that even if the stress FR1 concentrates on the rib portion 12, the variable pad 1 is less likely to be damaged.

Therefore, in the tensile test, even if the stress is concentrated on the ribs 12 and 13 when the rail RA expands and contracts at a low temperature of -20°C, because the resin portions 11b, 12b and 13b are all made of norbornene resin. , the rib portions 12 and 13 can be prevented from being damaged, that is, the variable pad 1 can be prevented from being damaged, and the variable pad 1 which is resistant to damage even at low temperatures can be obtained.

Although detailed description is omitted, as the second monomer, instead of tricyclopentadiene (Production Example 2), norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and other monomers of the above general formula Also when the compound represented by (1) was used, the same results as in Examples 2 to 4 were obtained in the tensile test. Similar results were also obtained when the polymerizable composition prepared according to Production Example 1 was used in place of Production Example 2. Furthermore, with respect to the various test pieces described above, similar results were obtained in the tensile test not only when test pieces prepared separately from the variable pad 1 were used, but also when test pieces cut from the variable pad 1 and processed were used. rice field.

(Example 4 and Comparative Examples 7 and 8)
In addition, the test piece of Comparative Example 7 made of the same polyester resin as the test piece of Comparative Example 3, the test piece of Comparative Example 8 made of the same polyester resin as the test piece of Comparative Example 4, and the test piece of Example 2 A test piece of Example 4 made of the same type of norbornene resin as the test piece was prepared, and the tensile test was performed under the same conditions except that the temperature was changed to -20 ° C. and 60 ° C. went. Table 3 shows the amount of elongation at break of the test piece, which was obtained by performing a tensile test on each of the test pieces of Comparative Examples 7, 8 and Example 4. Table 3 also shows the maximum stress and energy when the test piece broke.

For each of Comparative Example 7, Comparative Example 8 and Example 4, three specimens of the same type were used. In Table 3, the three test pieces of Comparative Example 7 are denoted as Comparative Example 7-1, Comparative Example 7-2, and Comparative Example 7-3, and the three test pieces of Comparative Example 8 are labeled as Comparative Example 8-1. , Comparative Examples 8-2 and 8-3, and the three test pieces of Example 4 are indicated as Examples 4-1, 4-2 and 4-3.

Although graphical representation is omitted, as shown in Table 3, the test piece of Comparative Example 7 made of polyester resin had an elongation amount when the test piece was broken was 16 to 22 mm for three test pieces of the same type. and the average value among the three test pieces was 18 mm. In addition, for the test piece of Comparative Example 8 made of polyester resin, the elongation amount when the test piece was broken was 42 to 56 mm for three test pieces of the same type, and the average value among the three test pieces was was 49 mm. On the other hand, the test pieces of Example 4 made of norbornene-based resin did not break even when the elongations of the three test pieces exceeded 65 mm, 75 mm and 75 mm, respectively. In Table 3, for example, ">65" indicates that the test piece did not break even when the elongation amount of the test piece exceeded 65 mm.

However, for the test piece of Comparative Example 7 made of polyester resin, the maximum stress when the test piece broke was 37 to 38 MPa for the three test pieces of the same type, and the average value among the three test pieces was It was 38 MPa. In addition, for the test piece of Comparative Example 8 made of polyester resin, the maximum stress when the test piece broke was 9 to 10 MPa for three test pieces of the same type, and the average value among the three test pieces was It was 9 MPa. On the other hand, the test pieces of Example 4 made of norbornene-based resin did not break even when the maximum stresses exceeded 33 MPa, 34 MPa and 35 MPa in three test pieces of the same type.

In addition, for the test piece of Comparative Example 7 made of polyester resin, the energy when the test piece broke was 14 to 22 J for the three test pieces of the same type, and the average value among the three test pieces was 17 J. Met. In addition, for the test piece of Comparative Example 8 made of polyester resin, the energy when the test piece broke was 9 to 15 J for the three test pieces of the same type, and the average value among the three test pieces was 12 J. Met. On the other hand, the test pieces of Example 4 made of norbornene-based resin did not break even when the energies exceeded 66J, 83J and 84J in three test pieces of the same type.

From Table 3, it can be seen that the energy at (assumed to be) breakage in Example 4 is greater than the energy at breakage in any of Comparative Examples 7 and 8. It has been clarified that the energy at (assumed) fracture of the norbornene-based resin is higher than the energy at the fracture of the polyester-based resin.

Summarizing the above results, the present inventors found that in a tensile test, a test piece made of norbornene-based resin exhibited higher strength than a test piece made of polyester-based resin in a wide temperature range from -20°C to 60°C. found to have

That is, of the manufactured test piece TE2, the upper (fourth side) end EP2 in the length direction (X3 direction) of the test piece TE2 is held by the upper gripper 33 as an upper holding portion, and the test piece TE2 is held. The lower gripper 34 as a lower holding part holds the end EP3 on the lower side (the side opposite to the fourth side) in the length direction (X3 direction), and the test piece TE2 is held in the length direction (X3 direction). ) at a tensile speed of 20 mm/min and a temperature of 60° C., the test piece TE2 is stretched in the longitudinal direction (X3 direction ) was subjected to a tensile test. When a tensile test was performed under these conditions, it became clear that the energy at breakage of the test piece TE2 exceeded 66J.

[Compression test]
Next, test pieces of Example 5 and Comparative Examples 9 and 10 were produced, and a compression test was performed on the produced test pieces.

(Example 5 and Comparative Examples 9 and 10)
A polymer 14 ( 3) and having a width of 13 mm, a thickness of 13 mm and a length of 13 mm. JIS K 7181 "Plastics - Determination of compression characteristics" was applied to the prepared test piece under the conditions of -20 ° C., 23 ° C. or 60 ° C. with a compression speed of 1 mm / min in the length direction of the test piece. A compression test was performed based on JIS K 6911 "General Test Methods for Thermosetting Plastics". Specifically, the test piece was compressed until it broke. From the relationship between the stress and strain measured at this time, the compressive strength σ _M (MPa) is obtained by the following formula (Equation 1), and the compressive yield point (also referred to as compressive yield stress) σ _y (MPa) is obtained by the following equation (Equation 2) ), and the compression elastic modulus E _c (MPa) was determined by the following formula (Equation 3).
σ _M =F _M /(bh) (Equation 1)
Here, FM is the maximum load (N) until _breakage , b is the test piece width (mm), and h is the test piece thickness (mm).
σ _y =F _y /(bh) (Equation 2)
where _Fy is the yield load (N).
E _c =(σ ₂ −σ ₁ )/(ε ₂ −ε ₁ ) (equation 3)
where σ ₁ is the stress (MPa) at strain ε ₁ and σ ₂ is the stress (MPa) at strain ε ₂ . The compressive elastic modulus in this compression test was determined from the strain range from ε ₁ =0.005 to ε ₂ =0.01.

10 and 11 and Table 4 show the results of compression elastic modulus and compression yield point obtained for the test pieces of Example 5 and Comparative Examples 9 and 10 in this manner. 10 is a graph showing the compression elastic modulus obtained by performing a compression test on each test piece of Comparative Examples 9, 10 and 5. FIG. FIG. 11 is a graph showing compression yield points obtained by performing compression tests on the test pieces of Comparative Examples 9, 10 and 5. FIG.

As shown in FIG. 11 and Table 4, the compressive yield point of the test piece of Comparative Example 9 made of polyester resin is 58 to 159 MPa in the temperature range of -20 ° C. to 60 ° C., and 58 MPa at 60 ° C. Met. The compression yield point of the test piece of Comparative Example 10 made of polyester resin was 6 to 84 MPa in the temperature range of -20°C to 60°C, and 6 MPa at 60°C. The test piece of Example 5 made of norbornene resin had a compression yield point of 52 to 92 MPa in the temperature range of -20°C to 60°C, and 52 MPa at 60°C. That is, the compression yield point of the test piece of Example 5 made of the norbornene resin was 52 MPa or higher at any temperature of -20°C, 23°C and 60°C.

In addition, the ratio of the compression yield point at -20 ° C. to the compression yield point at 60 ° C. of the test piece of Example 5 was 1.8, and the similar ratio of the test piece of Comparative Example 9 was 2.7. It was smaller than the similar ratio of 14 for the specimen of Example 10. That is, the temperature dependence of the compression yield point of Example 5 was smaller than the temperature dependence of the compression yield point of Comparative Examples 9 and 10.

It is generally considered desirable for the strength of the variable pad to have a "compression yield point of 20 MPa or more". In addition, the test piece of Comparative Example 9 made of the polyester resin had a compression yield point of 6 MPa at 60° C., and did not satisfy the above-described condition of "a compression yield point of 20 MPa or more".

On the other hand, in the test piece of Example 5 made of norbornene-based resin, the compression yield point is 52 MPa even at 60 ° C., and in a wide temperature range from -20 ° C. to 60 ° C., the condition that "the compression yield point is 20 MPa or more". was easily satisfied. That is, in a wide temperature range from -20 ° C. to 60 ° C., the test piece made of norbornene resin has higher strength than the test piece made of polyester resin, and the test piece made of norbornene resin is polyester It was found to have a compression yield point higher than that of the test piece made of resin.

Although detailed description is omitted, as the second monomer, instead of tricyclopentadiene (Production Example 2), norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and other monomers of the above general formula Also when the compound represented by (1) was used, the same results as in Example 5 were obtained in the compression test. Similar results were also obtained when the polymerizable composition prepared according to Production Example 1 was used in place of Production Example 2. Furthermore, with respect to the above various test pieces, similar results were obtained in the compression test not only when test pieces prepared separately from the variable pad 1 were used, but also when test pieces cut from the variable pad 1 and processed were used. rice field.

Although the invention made by the present inventor has been specifically described based on the embodiment, the invention is not limited to the above embodiment, and can be variously modified without departing from the gist of the invention. Needless to say.

Within the scope of the idea of the present invention, those skilled in the art can conceive of various modifications and modifications, and it is understood that these modifications and modifications also fall within the scope of the present invention.

For example, a person skilled in the art may appropriately add, delete, or change the design of components, or add, omit, or change the conditions of the above-described embodiments. As long as it has the gist, it is included in the scope of the present invention.

The present invention is effective when applied to variable pads.

1 variable pad 1a, 11a, 12a, 13a bag body 1b, 11b, 12b, 13b resin portion 1c outer surface layer 1d intermediate layer 1e inner surface layer 2 tie plate 3 track pad 4 support 5, 7, 36 bolt 6 plate Spring member 11 Body parts 12, 13 Rib part 14 Polymer 15 Polymeric composition 21 Cantilever bending test jigs 22, 32 Constant temperature bath 23 Holding part 24 Pressing part 24a Tip part 25, 35 Main body 25a Stopper 25b Corner part 26 Fixing Plate 27 Screw 31 Tensile test jig 33 Upper gripper 34 Lower gripper 35a Notch 35b, 37 Holding plate DS1 Distance EP1, EP2, EP3 Edge FR1 Stress HG1 Height LD1 Load MA1, MA2 Material testing machine PA1, PA2, PA3 Part PS1, PS2 Position RA Rail TE1, TE2 Specimen

Claims (11)

A variable pad inserted between a tie plate and a rail fixed on the tie plate and having a thickness adjusted to fill a gap between the tie plate and the rail,
a first bladder positioned between the tie plate and the rail;
a first resin portion filled inside the first bag body portion;
has
The first resin part is made of a polymer obtained by polymerizing a polymerizable composition containing a first monomer having a norbornene ring structure ,
The first bag body part includes a first inner surface layer made of polyethylene,
The variable pad , wherein the first inner surface layer made of polyethylene and the first resin portion are welded together to be bonded and integrated . A variable pad inserted between a tie plate and a rail fixed on the tie plate and having a thickness adjusted to fill a gap between the tie plate and the rail,
a first bladder positioned between the tie plate and the rail;
a first resin portion filled inside the first bag body portion;
has
The first resin part is made of a polymer obtained by polymerizing a polymerizable composition containing a first monomer having a norbornene ring structure ,
The first bag body part includes a first inner surface layer made of polyethylene,
The first inner surface layer made of polyethylene and the first resin portion are welded together to be bonded and integrated,
A first test piece made of the polymer and having a width of 10 mm, a thickness of 4 mm and a length of 80 mm was prepared, and the prepared first test piece was used as the first portion of the first test piece that was restrained. A load in the thickness direction of the first portion of the second portion is applied from the first end of the first test piece on the side of the second portion that is not restrained. It is fixed in a cantilever shape so that the distance to the third part is 11 mm, and the load is applied to the third part to deform it. When a bending test was performed in which the load was applied to the third portion to deform it under the conditions described above, the first test piece had a deformation amount of the third portion in the thickness direction of the first portion of 10 mm A variable pad that does not break even . A variable pad inserted between a tie plate and a rail fixed on the tie plate and having a thickness adjusted to fill a gap between the tie plate and the rail,
a first bladder positioned between the tie plate and the rail;
a first resin portion filled inside the first bag body portion;
has
The first resin part is made of a polymer obtained by polymerizing a polymerizable composition containing a first monomer having a norbornene ring structure ,
The first bag body part includes a first inner surface layer made of polyethylene,
The first inner surface layer made of polyethylene and the first resin portion are welded together to be bonded and integrated,
A first test piece made of the polymer and having a dumbbell shape of type 1B according to JIS K 7161-2 "Plastics-Determination of tensile properties-Part 2: Test conditions for molded, extruded and cast plastics" was prepared. Then, among the prepared first test pieces, the first end of the first side in the length direction of the first test piece is held by a first holding portion, and the length of the first test piece is A second holding portion holds a second end opposite to the first side in the direction, and the first holding portion is attached to the second holding portion such that the first test piece extends in the longitudinal direction. When a first tensile test was performed in which the first test piece was stretched in the length direction under the conditions of a first speed of relative movement of 20 mm / min and a temperature of -20 ° C., the first test The variable pad , wherein the first test piece has an elongation amount of 23 mm or more when the piece breaks . A variable pad inserted between a tie plate and a rail fixed on the tie plate and having a thickness adjusted to fill a gap between the tie plate and the rail,
a first bladder positioned between the tie plate and the rail;
a first resin portion filled inside the first bag body portion;
has
The first resin part is made of a polymer obtained by polymerizing a polymerizable composition containing a first monomer having a norbornene ring structure ,
The first bag body part includes a first inner surface layer made of polyethylene,
The first inner surface layer made of polyethylene and the first resin portion are welded together to be bonded and integrated,
A first test piece made of the polymer and having a dumbbell shape of type 1B according to JIS K 7161-2 "Plastics-Determination of tensile properties-Part 2: Test conditions for molded, extruded and cast plastics" was prepared. Then, among the prepared first test pieces, the first end of the first side in the length direction of the first test piece is held by a first holding portion, and the length of the first test piece is A second holding portion holds a second end opposite to the first side in the direction, and the first holding portion is attached to the second holding portion such that the first test piece extends in the longitudinal direction. When a first tensile test was performed in which the first test piece was stretched in the length direction under the conditions of a first speed of relative movement of 20 mm / min and a temperature of -20 ° C., the first test A variable pad having an energy of 38 J or more when the strip breaks . The variable pad according to any one of claims 1 to 4 ,
The variable pad is inserted between the tie plate and the rail so as to overlap a track pad made of an elastic plate. The variable pad according to any one of claims 1 to 5 ,
the rail extends in a first direction;
The variable pad further includes:
A second bag arranged on the second side in the first direction relative to the tie plate, the inside of which communicates with the inside of the first bag body portion, and which is formed integrally with the first bag body portion. body and
a second resin portion filled in the interior of the second bag body portion, made of the polymer, and integrally formed with the first resin portion;
has
The variable pad, wherein the thickness of the second resin portion is thicker than the thickness of the first resin portion. The variable pad according to any one of claims 1 to 6 ,
The polymerizable composition further comprises a second monomer having a norbornene ring structure and of a type different from that of the first monomer,
The first monomer is composed of dicyclopentadiene,
The second monomer has the following general formula (1):

(In general formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R ¹ and R ² or R ³ R ⁴ may together form an alkylidene group, and R ¹ and/or R ² and R ³ and/or R ⁴ may form a ring structure, p is 0, 1 or 2.)
A variable pad made of one or more compounds represented by In the variable pad according to claim 7 ,
The variable pad, wherein the second monomer is one or more selected from the group consisting of norbornene, tetracyclododecene, 5-ethylidenenorbornene, 8-ethylidenetetracyclododecene and tricyclopentadiene. The variable pad according to claim 7 or 8 ,
When the sum of the content of the first monomer in the polymerizable composition and the content of the second monomer in the polymerizable composition is 100 parts by mass, the content of the second monomer in the polymerizable composition A variable pad in an amount of 4 parts by mass or more. In the variable pad according to claim 3 or 4 ,
A second test piece made of the polymer and having a dumbbell shape of type 1B according to JIS K 7161-2 "Plastics - Determination of tensile properties - Part 2: Test conditions for molded, extruded and cast plastics" was prepared. Then, of the second test piece thus produced, the third end portion on the third side in the length direction of the second test piece is held by a third holding portion, and the length of the second test piece is A fourth holding portion holds a fourth end opposite to the third side in the direction, and the third holding portion is attached to the fourth holding portion such that the second test piece extends in the longitudinal direction. When a second tensile test was performed in which the second test piece was stretched in the length direction under the conditions of a second speed of relative movement of 20 mm / min and a temperature of 60 ° C., the second test piece A variable pad with more than 66 J of energy at break. In the variable pad according to claim 3, 4 or 10 ,
A third test piece made of the polymer and having a width of 13 mm, a thickness of 13 mm and a length of 13 mm was prepared, and the third speed of compression in the length direction of the prepared third test piece was set to 1 mm/min. When performing a compression test in which the third test piece is compressed in the longitudinal direction based on JIS K 7181 "Plastics - Determination of compression properties" and JIS K 6911 "General test method for thermosetting plastics" 2. The variable pad, wherein the compressive yield point of the third test piece is 52 MPa or more at any of -20°C, 23°C and 60°C.

Images