JP5005837B1 - ADAPTER AND METHOD FOR PRODUCING THERMOPLASTIC RESIN MOLDED ARTICLE - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adapter capable of making the temperature of a molten thermoplastic resin extruded from an extruder substantially uniform as a whole.
An adapter 1 of the present invention is used by being interposed between an extruder 6 and a mold 3, and a resin is provided in an adapter body 2 in which a resin flow path 21 through which a thermoplastic resin can flow is formed. A first cooling flow path 22 for flowing a cooling medium for cooling the thermoplastic resin flowing in the flow path 21 is provided, and the cooling pipe body 4 is placed in the resin flow path 21 of the adapter body 2. The second cooling flow path 41 is arranged to cool the synthetic resin flowing through the resin flow path 21 through the cooling pipe body 4.
[Selection] Figure 1

Description

  The present invention relates to an adapter used by being interposed between an extruder and a mold and a method for producing a thermoplastic resin molded article.

  Conventionally, a thermoplastic resin molded article having a desired shape is manufactured by supplying a thermoplastic resin to an extruder, melt-kneading, and then supplying it to a mold connected to the extruder via an adapter. Yes.

  In Patent Document 1, a thermoplastic resin made of a thermoplastic resin and a filler is provided by an extrusion molding machine in which a shaping die and a cooling die directly connected thereto are provided on the outlet side of an extruder main body comprising a screw and a barrel. A method for producing a thermoplastic resin molded article that is solidified and extruded using a composition, wherein an inner diameter of an outlet provided on an adapter provided between an outlet side of the extruder body and a shaping mold is an inner diameter of a barrel of the extruder 80% to 100%, and there is no resistor between the adapter and the extruder and the molding die other than the reduced inner diameter of the adapter to block the passage of the thermoplastic resin composition, and the extruder body Has disclosed a method for producing a thermoplastic resin molded article that is extruded by setting the barrel temperature in the vicinity of the outlet to a temperature not higher than the melting point of the thermoplastic resin.

  However, the adapter used in the method for producing a thermoplastic resin molded body does not have any resistor that blocks the passage of the thermoplastic resin composition other than the reduced diameter. On the other hand, in the extruder, the thermoplastic resin is melt-kneaded by the screw, and the shear stress applied to the thermoplastic resin by the screw increases as the screw approaches the rotation axis of the screw. Thus, the temperature is high, and the temperature of the thermoplastic resin tends to increase as it approaches the center in the barrel of the extruder.

  And since the adapter is not provided with any resistor in the passage of the thermoplastic resin composition, the thermoplastic resin that circulates in the adapter is supplied to the mold while maintaining the above temperature difference substantially. The thermoplastic resin that circulates in the vicinity of the center portion in the adapter and the thermoplastic resin that circulates in the vicinity of the outside in the adapter are different in melt viscosity because of their different temperatures. There is a problem that the thermoplastic resin cannot be smoothly extruded from the mold.

  In addition, when the thermoplastic resin supplied to the extruder contains a crosslinking agent such as an organic peroxide or a foaming agent, the center portion of the adapter There arises a problem that the crosslinking agent and the foaming agent contained in the thermoplastic resin circulating in the vicinity are unexpectedly decomposed.

  Therefore, when attempting to decompose the foaming agent and the crosslinking agent by lowering the barrel temperature of the extruder, the temperature of the thermoplastic resin circulating in the vicinity of the outside in the adapter becomes low, and as a result, the thermoplastic resin Another problem is that the melt viscosity becomes high and the thermoplastic resin cannot be smoothly extruded from the mold.

JP 2001-71367 A

  The present invention is used between an extruder and a mold, and the temperature of the molten thermoplastic resin extruded from the extruder is generally uniform, and the flow rate of the entire thermoplastic resin is adjusted. Provided are an adapter capable of producing a thermoplastic resin molded article having a desired shape by extruding a thermoplastic resin from a mold in a substantially uniform manner and a method for producing a thermoplastic resin molded article using the adapter.

  The adapter of the present invention is an adapter that is used between an extruder and a mold, and the inside of the resin channel is formed in an adapter main body in which a resin channel through which a thermoplastic resin can flow is formed. A first cooling channel for circulating a cooling medium for cooling the circulating thermoplastic resin is provided, and a cooling pipe is provided in the resin channel of the adapter body. Is a second cooling channel for cooling the synthetic resin flowing through the resin channel.

  The adapter is characterized in that a plurality of connecting rods are integrally provided between opposing surfaces of the adapter main body and the cooling pipe body.

  In the above adapter, the connecting rod is formed so as to become narrower from the cooling pipe body toward the adapter main body.

  The adapter is characterized in that a plurality of connecting rods are radially and integrally provided between opposing surfaces of the adapter main body and the cooling pipe body.

  The method for producing a thermoplastic resin molded article according to the present invention is such that a thermoplastic resin containing one or both of a foaming agent and a crosslinking agent is supplied to an extruder and melt-kneaded, and connected to the extruder via an adapter. A method for producing a thermoplastic resin molded product extruded from a mold, wherein the adapter circulates in the resin flow path through an adapter body in which a resin flow path through which the thermoplastic resin can flow is formed. A first cooling flow path for circulating a cooling medium for cooling the thermoplastic resin is disposed, and a cooling pipe body is disposed in the resin flow path of the adapter body, and the cooling pipe body is disposed inside the cooling pipe body. It is a second cooling channel for cooling the synthetic resin flowing through the resin channel, and a cooling medium is circulated through the first cooling channel and the second cooling channel to circulate through the resin channel of the adapter. Cool the thermoplastic resin And characterized in that it.

  In the method for producing a thermoplastic resin molded article, the temperature of the cooling medium circulated through the first cooling channel is higher than the temperature of the cooling medium circulated through the second cooling channel.

  Since the adapter of the present invention has the configuration as described above, the cooling in which the thermoplastic resin flowing in the resin flow path of the adapter is passed through the first cooling flow path and the second cooling flow path. The medium can be cooled from both inside and outside, and the thermoplastic resin flowing through the resin flow path of the adapter can be brought to a generally uniform temperature as a whole.

  The adapter according to the present invention includes a first cooling channel and a second cooling channel that are independent of each other, and each of the first cooling channel and the second cooling channel is provided with cooling media having different temperatures. It is possible to cool the thermoplastic resin flowing in the resin flow path of the adapter at an appropriate temperature from both inside and outside, and easily cool the thermoplastic resin to a generally uniform temperature as a whole. can do.

  Therefore, since the thermoplastic resin is cooled and adjusted in the adapter so as to have a generally uniform temperature as described above, the thermoplastic resin has a generally uniform melt viscosity as a whole. A thermoplastic resin molded article having a desired shape can be extruded from the mold by smoothly supplying the thermoplastic resin to the mold connected to the adapter.

  As described above, the thermoplastic resin in the adapter can be adjusted so as to have a proper and substantially uniform temperature as a whole, and a thermally decomposable additive that decomposes by heat, such as a foaming agent and a crosslinking agent, is provided. Even when it is contained in a thermoplastic resin, it effectively prevents a situation in which the thermoplastic resin is partially overheated and the thermally decomposable additive in the thermoplastic resin is unexpectedly decomposed. can do.

  In the above adapter, when a plurality of connecting rods are integrally provided between the opposing surfaces of the adapter main body and the cooling pipe body, the thermoplastic resin flowing in the resin flow path of the adapter is used. It is possible to cool the thermoplastic resin to an overall more uniform temperature by accelerating the mixing of the thermoplastic resin as a whole by colliding with the connecting rod.

  The thermoplastic resin is melt-kneaded in the extruder and then supplied to the adapter, but the thermoplastic resin is melt-kneaded by the screw in the extruder, and is added to the thermoplastic resin by the screw as it gets closer to the rotation axis of the screw. As shear stress increases, the closer the thermoplastic resin is to the rotation axis of the screw, the more heated and the higher the temperature becomes. The closer the thermoplastic resin gets to the center in the barrel of the extruder, the higher the temperature becomes. .

  Therefore, the temperature of the thermoplastic resin flowing in the resin flow path of the adapter is likely to be higher as the temperature of the thermoplastic resin flowing in the resin flow path. From the adapter main body to the cooling tube body, so that the inner wall of the adapter is relatively distributed. The higher the temperature of the thermoplastic resin, the greater the degree of mixing at the time of collision with the connecting rod, and the more effective cooling of the thermoplastic resin within the adapter to achieve a substantially uniform temperature overall. can do.

  In the above adapter, when a plurality of connecting rods are provided radially and integrally between the opposing surfaces of the adapter body and the cooling tube body, the thermoplastic resin flowing in the resin flow path of the adapter body Can be efficiently mixed as a whole, and the thermoplastic resin can be more effectively cooled in the adapter so that the temperature is generally uniform.

It is a partial sectional view showing the adapter of the present invention. It is the partial cross section figure which showed a part of adapter body. It is sectional drawing which showed the adapter. It is sectional drawing which showed the adapter.

  An example of the adapter of the present invention will be described with reference to the drawings. As shown in FIG. 1, the adapter 1 is connected to a discharge port of a general-purpose extruder 6 via a general-purpose connector 7 with a flow rate adjusting valve as necessary.

  The adapter 1 includes a cylindrical adapter main body 2 having a predetermined length, and the adapter main body 2 is formed with a resin flow channel 21 extending in the length direction and having both ends opened. The opening is formed in the resin inflow port 21a, and the other end opening is formed in the resin outflow port 21b. Then, the resin inlet 21a of the adapter body 2 is connected to and communicated with the discharge port of the extruder 6 through the connector 7 with a flow rate adjusting valve as necessary, and the resin outlet 21b of the adapter body 2 is connected. It is connected to and communicated with the resin inlet 31 of the mold 3.

  On the outer peripheral surface of the adapter main body 2, a first cooling channel 22 having an annular cross section is formed so as to surround the outer peripheral surface of the adapter main body at a portion excluding one end and a base end of the adapter main body 2. A cooling medium supply port 22a is formed at the end of the first cooling channel 22 on the resin inlet 21a side of the resin channel 21, and a resin outlet 21b of the resin channel 21 in the first cooling channel 22 is formed. A cooling medium discharge port 22b is formed at the end on the side. Then, a cooling medium adjusted to a predetermined temperature by a temperature adjusting device (not shown) is continuously supplied into the first cooling flow path 22 through the cooling medium supply port 22a, and the cooling medium is supplied in the first cooling flow path 22. It is configured so that the thermoplastic resin flowing in the resin flow path 21 of the adapter body 2 can be cooled completely from the outside by being filled with, and flows in the first cooling flow path 22 Then, the cooling medium after cooling the thermoplastic resin in the resin flow path 21 of the adapter body 2 is configured to be continuously discharged from the cooling medium discharge port 22b. The cooling medium discharged from the cooling medium discharge port 22b of the first cooling flow path 22 may be supplied again from the cooling medium supply port 22a after the temperature is adjusted. The cooling medium is not particularly limited, and examples thereof include oil, water, and organic compounds.

  Further, the cooling pipe body 4 is disposed in the resin flow path 21 of the adapter body 2 so that the length direction thereof matches the length direction of the resin flow path 21. Two cooling channels 41 are provided. Both ends of the cooling tube 4 are bent so that the adapter main body 2 penetrates in a watertight state and protrudes outside the adapter main body 2, and the end of the second cooling flow path 41 on the resin inlet 21 a side of the resin flow path 21 This portion is the cooling medium supply port 41a, and the end of the resin flow channel 21 on the resin outlet 21b side is the cooling medium discharge port 41b.

  Then, the cooling medium adjusted to a predetermined temperature by a temperature adjusting device (not shown) is continuously supplied into the second cooling flow path 41 through the cooling medium supply port 41a, and the second cooling flow path 41 is cooled in the second cooling flow path 41. It is configured so that the thermoplastic resin circulating in the resin flow path 21 of the adapter body 2 can be cooled from the inside by being filled with, and the adapter is distributed in the second cooling flow path 41 The cooling medium that has finished cooling the thermoplastic resin in the resin flow path 21 of the main body 2 is configured to be continuously discharged from the cooling medium discharge port 41b. The cooling medium discharged from the cooling medium discharge port 41b of the second cooling channel 41 may be supplied again from the cooling medium supply port 41a after the temperature is adjusted. The cooling medium is not particularly limited, and examples thereof include oil, water, and organic compounds.

  Further, as shown in FIGS. 2 to 4, a plurality of connecting rods 5, 5... Are arranged between the opposing surfaces of the cooling pipe body 4 and the adapter body 2 so as to connect the opposing surfaces. It is provided, and it is comprised so that it may become thin toward the adapter main body 2 from the cooling pipe body 4. FIG. Specifically, when the flow direction of the thermoplastic resin flowing through the resin flow path 21 of the adapter main body 2 is the front direction, the connecting rod 5 has a rectangular front shape and a triangular side shape. The shape is formed so as to become narrower from the cooling tube body 4 toward the adapter main body 2.

  As described above, the connecting rod 5 is configured to become narrower from the cooling tube body 4 toward the adapter main body 2, whereby the inside of the resin flow path 21 of the adapter main body 2 is circulated and the temperature becomes relatively high. The higher the thermoplastic resin is, the greater the degree of mixing when it collides with the connecting rod 5 and the effective cooling of the thermoplastic resin in the adapter 1 so that the temperature is generally uniform throughout. it can.

  The connecting rods 5 are arranged at predetermined intervals in the circumferential direction of the cooling pipe body 4 and are arranged radially around the cooling pipe body 4, and a plurality of these radially arranged connections are provided. A plurality of sets of connecting rod groups 51, 51... Are arranged at predetermined intervals in the flow direction of the thermoplastic resin flowing in the resin flow path 21 of the adapter body 2. Has been. 1 to 5 show a case where a set of connecting rod groups 51 is composed of three connecting rods 5, it may be two or four or more.

  And between the connecting rod groups 51 and 51 adjacent to each other, the connecting rods 5a and 5b are configured not to overlap each other in the flow direction of the thermoplastic resin flowing in the resin flow path 21 of the adapter body 2. The thermoplastic resin flowing in the resin flow path 21 of the adapter body 2 can be uniformly mixed as a whole.

  In this way, by arranging the connecting rod 5, the thermoplastic resin flowing in the resin flow path 21 of the adapter body 2 can be mixed by the connecting rod 5 as a whole, and the thermoplastic resin in the adapter 1 can be mixed. Can be effectively cooled so as to obtain a substantially uniform temperature as a whole.

  A mold 3 is connected to the adapter body 2, and the resin outlet 21 b of the adapter body 2 and the resin inlet 31 of the mold 3 are connected and communicated with each other. In addition, the metal mold | die 3 can use a general purpose metal mold | die in extrusion molding.

  Next, a procedure for extruding a thermoplastic resin molded product using the adapter 1 will be described. First, a thermoplastic resin is supplied to the extruder 6 and melted and kneaded, and is melted into the resin flow path 21 of the adapter body 2 through the discharge port of the extruder and the resin inlet 21a of the resin flow path 21 of the adapter body 2. A thermoplastic resin is continuously supplied. The adapter 1 is particularly effective when the thermoplastic resin contains a thermally decomposable additive that decomposes by heat, such as a foaming agent or a crosslinking agent.

  Examples of the foaming agent include azodicarbonamide, benzenesulfonylhydrazide, dinitrosopentamethylenetetramine, toluenesulfonylhydrazide, 4,4-oxybis (benzenesulfonylhydrazide), and the like. Two or more types may be used in combination.

  Examples of the crosslinking agent include 2,4-dichlorobenzoyl peroxide, benzoyl peroxide, t-butyl perbenzoate, cumyl hydroperoxide, t-butyl hydroperoxide, 1,1-di (t-butyl peroxy). ) -3,3,5-trimethylhexane, n-butyl-4,4-di (t-butylperoxy) valerate, α, α'-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl Examples include organic peroxides such as -2,5-di (t-butylperoxy) hexyne-3 and t-butylperoxycumene. In addition, a crosslinking agent may be used independently or 2 or more types may be used together.

  On the other hand, the cooling medium adjusted to a predetermined temperature by a temperature adjusting device (not shown) is continuously supplied into the first cooling flow path 22 of the adapter 1 and the first cooling flow path 22 is filled with the cooling medium. Thus, the thermoplastic resin flowing in the resin flow path 21 of the adapter main body 2 is entirely cooled from the outside. The cooling medium that has circulated through the first cooling flow path 22 and has cooled the thermoplastic resin in the resin flow path 21 of the adapter body 2 is continuously discharged from the cooling medium discharge port 22b.

  At the same time, the cooling medium adjusted to a predetermined temperature by a temperature adjusting device (not shown) is continuously supplied into the second cooling channel 41 through the cooling medium supply port 41a, By filling with a cooling medium, the thermoplastic resin flowing through the resin flow path 21 of the adapter body 2 is cooled from the inside. The cooling medium that has circulated in the second cooling flow path 41 and has cooled the thermoplastic resin in the resin flow path 21 of the adapter body 2 is continuously discharged from the cooling medium discharge port 41b.

  The temperature of the cooling medium circulated in the second cooling channel 41 is adjusted to be lower than the temperature of the cooling medium circulated in the first cooling channel 22. This is because the temperature of the thermoplastic resin flowing in the resin flow path 21 of the adapter 1 tends to increase as the temperature of the thermoplastic resin flowing inside the resin flow path 21 increases. The temperature of the cooling medium flowing in the cooling flow path 41 is made lower than the temperature of the cooling medium flowing in the first cooling flow path 22, thereby circulating the inside of the resin flow path 21. The thermoplastic resin can be cooled more strongly, and the thermoplastic resin can be cooled so that the thermoplastic resin has a substantially uniform temperature as a whole.

  Further, the thermoplastic resin flowing in the resin flow path 21 of the adapter 1 collides with the plurality of connecting rods 5, 5... While flowing in the resin flow path 21, and is mixed at the time of the collision. The thermoplastic resin is cooled to a more uniform temperature overall. Further, the connecting rod 5 is formed so as to become narrower from the cooling tube body 4 toward the adapter main body 21, and is mixed so large that it becomes a thermoplastic resin flowing inside the resin flow path 21 of the adapter main body 2. The thermoplastic resin that tends to reach a relatively high temperature is mixed to a greater extent, and thus the thermoplastic resin is cooled to a substantially uniform temperature as a whole.

  When the thermoplastic resin contains a thermally decomposable additive, if the thermoplastic resin is unexpectedly heated excessively, the thermally decomposable additive may be rapidly decomposed in large quantities. However, in the adapter 1, the thermoplastic resin is cooled from the inside and outside by the cooling medium flowing in the first cooling flow path 22 and the cooling medium flowing in the second cooling flow path 41. At the same time, since the thermoplastic resin is mixed by the connecting rod 5, the thermoplastic resin is not unexpectedly heated excessively, and the pyrolyzable additive is not rapidly decomposed in large quantities.

  As described above, since the thermoplastic resin is cooled to a substantially uniform temperature as a whole while flowing through the resin flow path 21 of the adapter 1, the thermoplastic resin has a substantially uniform melt viscosity as a whole. In this state, the thermoplastic resin is continuously fed to the mold 3 through the resin outlet 21b of the resin flow path 21 of the adapter 1 and continuously at substantially the same flow rate through the resin inlet 31. Supplied.

  Since the thermoplastic resin continuously supplied to the mold 3 has substantially the same melt viscosity as a whole, no stagnation occurs in the mold 3 and the thermoplastic resin smoothly flows from the mold 3. It is possible to extrude a thermoplastic resin molded article that has been extruded into a desired shape.

1 Adapter 2 Adapter body 3 Mold 4 Cooling tube 5 Connection rod
51 Connecting rod group 6 Extruder 7 Connector
21 Resin channel
21a Resin inlet
21b Resin outlet
22 First cooling flow path
22a Cooling medium supply port
22b Cooling medium outlet
31 Resin inlet
41 Second cooling flow path
41a Cooling medium supply port
41b Cooling medium outlet

Claims (7)

An adapter used between an extruder and a mold, wherein a thermoplastic resin that circulates in the resin flow path is formed in an adapter body in which a resin flow path through which the thermoplastic resin can flow is formed. A first cooling flow path for circulating a cooling medium for cooling is provided, and a cooling pipe body is disposed in the resin flow path of the adapter body, and the cooling pipe body is disposed in the resin flow path. An adapter characterized in that it is a second cooling flow path for cooling the synthetic resin flowing through. The adapter according to claim 1, wherein a plurality of connecting rods are integrally provided between opposing surfaces of the adapter main body and the cooling pipe body. The adapter according to claim 2, wherein the connecting rod is formed so as to become narrower from the cooling pipe body toward the adapter main body. The adapter according to claim 2 or 3, wherein a plurality of connecting rods are integrally provided radially between opposing surfaces of the adapter main body and the cooling pipe body. A method for producing a thermoplastic resin molded article in which a thermoplastic resin is supplied to an extruder, melted and kneaded, and extruded from a mold connected to the extruder via an adapter, wherein the adapter is heated inside. A first cooling channel for circulating a cooling medium for cooling the thermoplastic resin that circulates in the resin channel is provided in the adapter body in which a resin channel through which the plastic resin can circulate is formed. A cooling pipe is disposed in the resin flow path of the adapter body, and the second cooling flow path for cooling the synthetic resin flowing through the resin flow path in the cooling pipe is provided in the first cooling A method for producing a thermoplastic resin molded article, comprising cooling a thermoplastic resin flowing through the resin flow path of the adapter by flowing a cooling medium through the flow path and the second cooling flow path. 6. The method for producing a thermoplastic resin molded article according to claim 5, wherein the thermoplastic resin contains a thermally decomposable additive that is decomposed by heat. The thermoplastic resin molding according to claim 5 or 6, wherein the temperature of the cooling medium flowing through the second cooling flow path is lower than the temperature of the cooling medium flowing through the first cooling flow path. Product manufacturing method.

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