WO1987007283A1 - Eps combination foam piece, procedure for its manufacturing, and its use - Google Patents

Eps combination foam piece, procedure for its manufacturing, and its use Download PDF

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Publication number
WO1987007283A1
WO1987007283A1 PCT/FI1987/000074 FI8700074W WO8707283A1 WO 1987007283 A1 WO1987007283 A1 WO 1987007283A1 FI 8700074 W FI8700074 W FI 8700074W WO 8707283 A1 WO8707283 A1 WO 8707283A1
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WO
WIPO (PCT)
Prior art keywords
foam
eps
piece
binding agent
sheet
Prior art date
Application number
PCT/FI1987/000074
Other languages
French (fr)
Inventor
Martin Frankenhaeuser
Original Assignee
Neste Oy
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Neste Oy filed Critical Neste Oy
Publication of WO1987007283A1 publication Critical patent/WO1987007283A1/en
Priority to NO880125A priority Critical patent/NO880125L/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/35—Composite foams, i.e. continuous macromolecular foams containing discontinuous cellular particles or fragments

Definitions

  • the invention concerns EPS combination foam pieces, a procedure for manufacturing same, and their use.
  • the invention concerns EPS combination foam pieces, and manufacturing thereof, which are composed of mixtures of EPS granules and a foam-like binding agent.
  • EPS prefoaming compound EPS-cell- forming polystyrene
  • EPS-cell- forming polystyrene EPS prefoaming compound
  • the difficulty has then been that the separate granules rise in the die or mould to the surface layer.
  • the EPS globules are easily damaged by the high mould temperature (>100°C).
  • the net is removed after the product has hardened.
  • One of the drawbacks of this procedure is that therein is needed a mould, and a net in said mould. For this reason the procedure is in actual practice restricted mainly to the manufacturing of rectangular pieces. Furthermore, it is not possible by this procedure to manufacture longitudinally continuous products, nor laminated products.
  • One of the objects of the present invention is an EPS combination foam piece which is free from the drawbacks described.
  • the EPS combination foam piece of the invention is characterized in that it consists of an EPS polystyrene sheet or shaped piece with spacious structure and which has been impregnated with a free-flowing foam- like binding agent which fills the free spaces between the polystyrene granules and solidifies therein.
  • EPS combination foam piece of the invention is used an EPS sheet or shaped piece with spacious structure which has open spaces amounting to between 10 and 30% of the total volume.
  • a sheet or shaped piece with spacious structure is here understood to mean a finished sheet or shaped piece made in a way known in itself in the art, by foaming in a mould, of EPS granules.
  • Such a product contains EPS granules cemented to each other, and it is self-coherent, in contrast to the loose EPS granules used in the above-cited Japanese Patent No. 56-120326(A).
  • the EPS sheet or shaped piece may also have the shape of a continuous web, and thus the invention also encompasses EPS combination foam products which are continuous in the longitudinal direction.
  • binding agent For binding agent, one may according to the invention use organic or inorganic hardening, foam-forming substances. The prerequisite is imposed on the binding agent that it will not corrode polystyrene, and that its foam-producing components in combination constitutes a free-flowing substance mix filling the spaces between the polystyrene globules and foaming and hardening in said spaces between globules.
  • the density of the binding agent has to be high enough (>30 kg/cm 3 ) to afford adequate mechanical properties and cold-endurance of the foam that is produced.
  • the binding agent may have open-cell or closed- cell structure.
  • the contribution of the binding agent to the ESP combination foam piece of the invention is advantageously less than 30% by volume. Hereby no such great amounts of heat are liberated at curing that damage to the EPS granules would incurred.
  • the low temperature also entails the advantage that the shrinkage occurring as the piece cools will be less.
  • the task of the binding agent is to fill and reinforce the EPS foam pieces and in special instances, e.g. in multi-ply structures, to attach the surface laminations directly in one single work step to the EPS combination foam piece serving as core material.
  • Suitable binding agents are, for instance: polyurethane resins, epoxy resins, and phenolic resins.
  • a recommendable binding agent is polyurethane.
  • the EPS conbination foam piece of the invention presents good heat resistance, that is, it tolerates temperatures higher than normal, without shrinkage. Particularly in those instances in which an opencell binding agent foam is used, the thermal expansion of the products is less than that of a conventional closed-cell, dense EPS sheet. Compared with equivalent foamed products which have been formed exclusively of the binding agent used in the product, the EPS combination foam product is considerably less expensive to manufacture. When used as a packaging material, the EPS combination foam product of the invention presents shock absorbing properties which are close to those of the best polyethylene foam.
  • the invention also concerns a procedure for manufacturing EPS combination foam pieces, said procedure being characterized in that an EPS Polystyrene foam piece with spacious structure is impregnated with a foamable, free-flowing binding agent which fills the free spaces between EPS granules and hardens therein.
  • binding agent to the EPS foam piece is accomplished simply, by adding a free-flowing substance mixture which forms foam- like binding agent, upon the foamed piece, whereby it will be absorbed in the spaces between the EPS granules, while at the same time foaming sets in.
  • This mode of application is advantageous when shaped pieces are being manufactured and the impregnated foamed piece is advan tageously kept in the mould during the curing time of the binding agent if the product being manufactured has a peculiar shape.
  • Binding agent application may, when manufacturing laminated products, also be between the lamination layers, whereby absorption of the binding agent, its foaming and cementing-on of the surface laminations all take place in one work step.
  • EPS foam sheet The handling of an EPS foam sheet is simple because the EPS globules remain interlocked without need to use any mould. Binding agent application may be accomplished e.g. in a press, or even on continucus-cperation impregnation lines which are used in manufacturing laminated products. Since the structure of the EPS piece is uniform and the volumetric contribution of the globules is 70 to 90%, the reaction heat will not raise the temperature of the product to such height that any collapse of EPS globules need be feared. This also entails the advantage that the cycle times are shorter than in the case of semi-hard integral foam applications, and that the shrinkage, which is an established problem, will be less.
  • binding agent may also take place at the point of use of the final product, e.g. in connection with the manufacturing of building construction elements or when lagging roofs of buildings on site.
  • ihe EPS combination foam products of the invention may be applied e.g. as lagging, or insulation, sheets or for footfall attenuation, when the binding agent foam component is soft, e.g. polyurethane, or to serve as insulation panel when a hard binding agent component is used.
  • the binding agent foam component is soft, e.g. polyurethane, or to serve as insulation panel when a hard binding agent component is used.
  • Products which are pressed into shape from sheet material may be manufactured by combining a surface lamination with the polystyrene in conjunction with the polyurethane addition. This enables finished products, e.g. lagging sheets appropriate for the ceiling of a car body, to be manufactured in one work step, using cold tools.
  • Fig. 1 presents graphically certain characteristics of the EPS combination foam piece of the invention.
  • Fig. 2 presents an embodiment of the EPS combination foam piece of the invention, in schematic section.
  • m Fig. 1 has been plotted the peak deceleration 6, as a function of static stress in kPa, and the impact attenuation factor C, as a function of work capacity in kJ/m 3 .
  • the ceiling cladding sheet of the invention in general has been indicated with reference numeral 10.
  • the ceiling cladding sheet 10 comprises a surface lamination 11 serving attachment, and a cladding surface lamination 12.
  • the cellular polystyrene (EPS) sheet with spacious structure inside the laminated structures 11 and 12 has been denoted with reference numeral 13 and the binding agent foam, with 14.
  • a ceiling cladding sheet for a car body was manufactured in that upon an EPS sheet with spacious structure of 10 mm thickness and with particle size abcut 5 mm, density abcut 15 g/dm 3 and empty volume about 10%, a polyol/isocyanate mixture was applied which had soft foam (rigid) starting time about 60 seconds and free density about 40 g/dm 3 .
  • the sheet was placed between surface laminations, in a press.
  • the core material (combination product or foam) of the multi-ply sheet thus produced had density about 40 g/dm 3 , i.e., 400 g/m 2 .
  • Fig. 2 is a general representation of the structure of this sheet.

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  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Laminated Bodies (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)

Abstract

EPS combination foam piece, a procedure for manufacturing same, and the use thereof. The EPS combination foam piece consists of a cellular polystyrene (EPS) sheet, or shaped body (13), with spacious structure and which has been impregnated with free-flowing foam-like binding agent (14) filling the spaces between polystyrene granules and hardening therein. Said free-flowing binding agent is polyurethane foam, phenolic foam or epoxy foam.

Description

EPS combination foam piece, procedure for its manufacturing, and its use
The invention concerns EPS combination foam pieces, a procedure for manufacturing same, and their use. In particular, the invention concerns EPS combination foam pieces, and manufacturing thereof, which are composed of mixtures of EPS granules and a foam-like binding agent.
It is known in the art to mix EPS prefoaming compound (EPS-cell- forming polystyrene) in the form of discrete granules and components producing polyurethane foam in manufacturing various products, e.g. mattresses, by die casting. The difficulty has then been that the separate granules rise in the die or mould to the surface layer. The EPS globules are easily damaged by the high mould temperature (>100°C).
Inthe Japanese Patent No. 56-120326(A), a problem solution is disclosed in which the reaction temperature cannot rise to such great height that the EPS globules would suffer damage. In said procedure, a box mould is used which is open on one side. The mould is filled with EPS granules and the open side of the mould is closed with a net which locks the EPS globules in place. The substance mix forming polyurethane foam is then poured into the mould. About 40% of the volume within the mould will then be available to be occupied by the polyurethane foam that is formed in the mould.
The net is removed after the product has hardened. One of the drawbacks of this procedure is that therein is needed a mould, and a net in said mould. For this reason the procedure is in actual practice restricted mainly to the manufacturing of rectangular pieces. Furthermore, it is not possible by this procedure to manufacture longitudinally continuous products, nor laminated products. One of the objects of the present invention is an EPS combination foam piece which is free from the drawbacks described. The EPS combination foam piece of the invention is characterized in that it consists of an EPS polystyrene sheet or shaped piece with spacious structure and which has been impregnated with a free-flowing foam- like binding agent which fills the free spaces between the polystyrene granules and solidifies therein.
It is thus understood that in the EPS combination foam piece of the invention is used an EPS sheet or shaped piece with spacious structure which has open spaces amounting to between 10 and 30% of the total volume. A sheet or shaped piece with spacious structure is here understood to mean a finished sheet or shaped piece made in a way known in itself in the art, by foaming in a mould, of EPS granules. Such a product contains EPS granules cemented to each other, and it is self-coherent, in contrast to the loose EPS granules used in the above-cited Japanese Patent No. 56-120326(A). The EPS sheet or shaped piece may also have the shape of a continuous web, and thus the invention also encompasses EPS combination foam products which are continuous in the longitudinal direction.
For binding agent, one may according to the invention use organic or inorganic hardening, foam-forming substances. The prerequisite is imposed on the binding agent that it will not corrode polystyrene, and that its foam-producing components in combination constitutes a free-flowing substance mix filling the spaces between the polystyrene globules and foaming and hardening in said spaces between globules. The density of the binding agent has to be high enough (>30 kg/cm3) to afford adequate mechanical properties and cold-endurance of the foam that is produced. The binding agent may have open-cell or closed- cell structure.
The contribution of the binding agent to the ESP combination foam piece of the invention is advantageously less than 30% by volume. Hereby no such great amounts of heat are liberated at curing that damage to the EPS granules would incurred. The low temperature also entails the advantage that the shrinkage occurring as the piece cools will be less.
The task of the binding agent is to fill and reinforce the EPS foam pieces and in special instances, e.g. in multi-ply structures, to attach the surface laminations directly in one single work step to the EPS combination foam piece serving as core material.
Suitable binding agents are, for instance: polyurethane resins, epoxy resins, and phenolic resins. A recommendable binding agent is polyurethane.
The EPS conbination foam piece of the invention presents good heat resistance, that is, it tolerates temperatures higher than normal, without shrinkage. Particularly in those instances in which an opencell binding agent foam is used, the thermal expansion of the products is less than that of a conventional closed-cell, dense EPS sheet. Compared with equivalent foamed products which have been formed exclusively of the binding agent used in the product, the EPS combination foam product is considerably less expensive to manufacture. When used as a packaging material, the EPS combination foam product of the invention presents shock absorbing properties which are close to those of the best polyethylene foam.
The invention also concerns a procedure for manufacturing EPS combination foam pieces, said procedure being characterized in that an EPS Polystyrene foam piece with spacious structure is impregnated with a foamable, free-flowing binding agent which fills the free spaces between EPS granules and hardens therein.
Application of the binding agent to the EPS foam piece is accomplished simply, by adding a free-flowing substance mixture which forms foam- like binding agent, upon the foamed piece, whereby it will be absorbed in the spaces between the EPS granules, while at the same time foaming sets in. This mode of application is advantageous when shaped pieces are being manufactured and the impregnated foamed piece is advan tageously kept in the mould during the curing time of the binding agent if the product being manufactured has a peculiar shape. Binding agent application may, when manufacturing laminated products, also be between the lamination layers, whereby absorption of the binding agent, its foaming and cementing-on of the surface laminations all take place in one work step.
The handling of an EPS foam sheet is simple because the EPS globules remain interlocked without need to use any mould. Binding agent application may be accomplished e.g. in a press, or even on continucus-cperation impregnation lines which are used in manufacturing laminated products. Since the structure of the EPS piece is uniform and the volumetric contribution of the globules is 70 to 90%, the reaction heat will not raise the temperature of the product to such height that any collapse of EPS globules need be feared. This also entails the advantage that the cycle times are shorter than in the case of semi-hard integral foam applications, and that the shrinkage, which is an established problem, will be less.
Application of the binding agent may also take place at the point of use of the final product, e.g. in connection with the manufacturing of building construction elements or when lagging roofs of buildings on site.
ihe EPS combination foam products of the invention may be applied e.g. as lagging, or insulation, sheets or for footfall attenuation, when the binding agent foam component is soft, e.g. polyurethane, or to serve as insulation panel when a hard binding agent component is used. In the latter case it is advantageous to use also surface lamination, whereby a high-strerngth laminated sheet structure is obtained in applications at a building site.
Products which are pressed into shape from sheet material may be manufactured by combining a surface lamination with the polystyrene in conjunction with the polyurethane addition. This enables finished products, e.g. lagging sheets appropriate for the ceiling of a car body, to be manufactured in one work step, using cold tools.
The invention is now described in detail, referring to an advantageous embodiment of the invention, presented in the figures of the attached drawings, yet to which the invention is not meant to be exclusively confined.
Fig. 1 presents graphically certain characteristics of the EPS combination foam piece of the invention.
Fig. 2 presents an embodiment of the EPS combination foam piece of the invention, in schematic section.
m Fig. 1 has been plotted the peak deceleration 6, as a function of static stress in kPa, and the impact attenuation factor C, as a function of work capacity in kJ/m3.
In Fig. 2, the ceiling cladding sheet of the invention in general has been indicated with reference numeral 10. In this embodiment example, the ceiling cladding sheet 10 comprises a surface lamination 11 serving attachment, and a cladding surface lamination 12. The cellular polystyrene (EPS) sheet with spacious structure inside the laminated structures 11 and 12 has been denoted with reference numeral 13 and the binding agent foam, with 14.
The invention is illustrated with the aid of the following examples.
Example 1
Upon an ESP sheet with spacious structure of 50 mm thickness and with particle size about 10 mm, density about 10-15 g/dm3 and empty (free space) volume about 25%, a polyol/isocyanate mixture was applied which had soft foam starting time about 15 seconds and free density about 20 g/dm3. The sheet was kept between polyethylene foils under a small weight. The combination foam product thus produced had density 34 g/dm3, and its impact attenuation factor was markedly superior to that of an ESP sheet with equivalent density, as can be seen in Fig.
1, where the deceleration and impact attenuation factors of EPS sheet, of the EPS combination foam product of the invention and of a polyethylene foam product have been compared.
Example 2
A ceiling cladding sheet for a car body was manufactured in that upon an EPS sheet with spacious structure of 10 mm thickness and with particle size abcut 5 mm, density abcut 15 g/dm3 and empty volume about 10%, a polyol/isocyanate mixture was applied which had soft foam (rigid) starting time about 60 seconds and free density about 40 g/dm3. The sheet was placed between surface laminations, in a press. The core material (combination product or foam) of the multi-ply sheet thus produced had density about 40 g/dm3, i.e., 400 g/m2. Fig. 2 is a general representation of the structure of this sheet.

Claims

Claims
1. An EPS combination foam piece (10), characterized in that it consists of a cellular polystyrene (EPS) sheet, or shaped body, (13) with spacious structure and which has been impregnated with free- flowing foam-like binding agent (14) filling the spaces between polystyrene granules and hardening therein.
2. Piece according to claim 1, characterized in that said free-flowing binding agent (14) is polyurethane foam, phenolic foam or epoxy foam.
3. Piece according to claim 1 or 2, characterized in that the volume weight of the EPS sheet or piece is higher than 8 kg/m3, the volume weight of the binding agent foam is at least 30 kg/m3 and the volume weight of the EPS combination foam piece obtained as product is over 20 kg/m3.
3. Piece according to any one of the preceding claims, characterized in that it is provided with a surface lamination (11,12).
4. Procedure for manufacturing an EPS combination foam piece (10) according to any one of claims 1-4, characterized in that it is manufactured by impregnating a cellular polystyrene (EPS) sheet, or shaped piece, (13) with spacious structure, with free-flowing binding agent (14) filling the free spaces between polystyrene granules and hardening therein.
6. Procedure according to claim 5, characterized in that the free- flowing binding agent (14) is polyurethane foam, phenolic foam or epoxy foam.
7. Procedure according to claim 5 or 6, characterized in that said sheet or shaped piece (13) is pressed into shape during the hardening time of the binding agent (14).
8. Procedure according to any one of the preceding claims 5-7, characterized in that to the combination foam piece (13) are attached surface lamination sheets (11) and/or surface claddings (12) simultaneously during hardening of the binding agent (14).
9. The use in a multi-ply sheet structure of a product according to any one of claims 1-4 or of a product manufactured by a procedure according to any one of claims 5-8.
10. The use as elastic lagging sheet, as rigid panel, as shaped panel or as packaging cushion of a product according to any one of claims 1-4 or of a product manufactured by a procedure according to any one of claims 5-8.
PCT/FI1987/000074 1986-05-29 1987-05-29 Eps combination foam piece, procedure for its manufacturing, and its use WO1987007283A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
NO880125A NO880125L (en) 1986-05-29 1988-01-13 PIECE OF EPS COMBINATION FOAM, PROCEDURE FOR MANUFACTURING THEREOF, AND ITS USE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI862291A FI862291A (en) 1986-05-29 1986-05-29 EPS-KOMBINATIONSSKUMSTYCKE, FOERFARANDE FOER DESS FRAMSTAELLNING OCH DESS ANVAENDNING.
FI862291 1986-05-29

Publications (1)

Publication Number Publication Date
WO1987007283A1 true WO1987007283A1 (en) 1987-12-03

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PCT/FI1987/000074 WO1987007283A1 (en) 1986-05-29 1987-05-29 Eps combination foam piece, procedure for its manufacturing, and its use

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EP (1) EP0268658A1 (en)
FI (1) FI862291A (en)
WO (1) WO1987007283A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102558598A (en) * 2011-12-14 2012-07-11 曾首元 Preparation method of black gray expandable polystyrene
CN108120219A (en) * 2018-03-11 2018-06-05 滁州市新康达金属制品有限公司 Refrigerator doors and its manufacturing method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1024331A (en) * 1962-01-26 1966-03-30 Basf Ag Composite expanded plastics
GB1172923A (en) * 1966-11-03 1969-12-03 Saint Gobain Lightweight Building Material
GB1444105A (en) * 1972-12-20 1976-07-28 Basf Ag Manufacture of soft and resilient composite polyurethane foams

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1024331A (en) * 1962-01-26 1966-03-30 Basf Ag Composite expanded plastics
GB1172923A (en) * 1966-11-03 1969-12-03 Saint Gobain Lightweight Building Material
GB1444105A (en) * 1972-12-20 1976-07-28 Basf Ag Manufacture of soft and resilient composite polyurethane foams

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
CHEMICAL ABSTRACTS, Vol 84 (1976), Abstract No 84:74973a *
CHEMICAL ABSTRACTS, Vol 85 (1976), Abstract No 85:178594q, *
CHEMICAL ABSTRACTS, Vol 88 (1978), Abstract No 88:106383j, published 1976 *
CHEMICAL ABSTRACTS, Vol 94, (1981), Abstract No 94:209968g, AU 361 719 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102558598A (en) * 2011-12-14 2012-07-11 曾首元 Preparation method of black gray expandable polystyrene
CN108120219A (en) * 2018-03-11 2018-06-05 滁州市新康达金属制品有限公司 Refrigerator doors and its manufacturing method

Also Published As

Publication number Publication date
FI862291A (en) 1987-11-30
EP0268658A1 (en) 1988-06-01
FI862291A0 (en) 1986-05-29

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