GB2139629A - Method for making shaped foam articles of a vinyl chloride resin - Google Patents
Method for making shaped foam articles of a vinyl chloride resin Download PDFInfo
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- GB2139629A GB2139629A GB08409660A GB8409660A GB2139629A GB 2139629 A GB2139629 A GB 2139629A GB 08409660 A GB08409660 A GB 08409660A GB 8409660 A GB8409660 A GB 8409660A GB 2139629 A GB2139629 A GB 2139629A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/0061—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof characterized by the use of several polymeric components
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/34—Auxiliary operations
- B29C44/36—Feeding the material to be shaped
- B29C44/46—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length
- B29C44/50—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length using pressure difference, e.g. by extrusion or by spraying
- B29C44/505—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length using pressure difference, e.g. by extrusion or by spraying extruding the compound through a flat die
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- 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
- C08J9/0066—Use of inorganic compounding ingredients
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
- C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
- C08J9/14—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent organic
- C08J9/141—Hydrocarbons
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2027/00—Use of polyvinylhalogenides or derivatives thereof as moulding material
- B29K2027/06—PVC, i.e. polyvinylchloride
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- 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
- C08J2327/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
- C08J2327/02—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
- C08J2327/04—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing chlorine atoms
- C08J2327/06—Homopolymers or copolymers of vinyl chloride
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- 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
- C08J2433/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Polymers & Plastics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Molding Of Porous Articles (AREA)
Abstract
Shaped foam articles of a vinyl chloride resin are made by injecting an organic solvent-type blowing agent under pressurization into a composition comprising 100 parts by wt. of a vinyl chloride resin, 0.5-30 parts of an acrylic resin and at least 10 parts of an inorganic filler in a heated and gelled condition in an extruder out of which the resin composition is extruded to complete foaming. The shaped foam article has a fine and uniform cellular structure and controlled bulk density and also is imparted with improved characteristics such as thermal resistance, flame retardancy, weathering resistance and solvent resistance.
Description
SPECIFICATION
Method for making shaped foam articles of a polyvinyl chloride resin
BACKGROUND OF THE INVENTION
This invention concerns a method for making shaped foam articles of a polyvinyl chloride-based resin, more particularly, an inexpensive method for producing shaped foam articles of a polyvinyl chloride-based resin of high expansion having a very fine and uniform structure by use of a polyvinyl chloride-based resin compounded with a large amount of an inorganic filler in a continuous process.
Conventionally, several processes are known and currently practiced as the manufacturing method for shaped foam articles of a polyvinyl chloride-based resin (referred to merely as a PVC resin hereinbelow). They are, for example: (1) a method of subjecting a PVC resin admixed with a so-called decomposable blowing agent or foaming agent which produces gases by thermal decomposition to cause foaming of the resin composition under heating simultaneously with shaping using an extrusion molding machine, an injection molding machine or the like; (2) a method of obtaining desired products by subjecting a pasty mass or plastisol prepared by compounding a PVC resin with a plasticizer to mechanical foaming or by subjecting the plastisol to simultaneous gelation and foaming under heating after admixture of a decomposable blowing agent;; (3) a method of preparing foamed articles by heating a mixture containing a decomposable blowing agent after preliminary shaping by rolling at a temperature lower than the decomposition temperature of the blowing agent; and (4) a method of filling a metal mold with a mixture of a PVC resin and a decomposable blowing agent, optionally together with further admixture of a volatilizable organic blowing agent, an organic solvent capable of swelling the resin and a softening agent, subjecting the above filling mass to melting-gelation under heating and compression followed by cooling and subsequent second heating to effect foaming.
Each of the above methods, however, has certain deficiencies such as incapability of giving rigid or semi-rigid foamed articles with a high degree of expansion in the cases of the above first to third methods and the high production cost of the final products as a consequence of the longer processing time for foamed articles in the above given fourth method which is necessarily a batch-wise process involving complicated steps.
SUMMARY OF THE INVENTION
As hereinafter described in detail, the present invention provides an easy and continuous process for the production of shaped foam articles of a PVC resin compounded with a large amount of an inorganic filler with a high ratio of expansion to impart a fine and uniform cell structure by applying a technique of simultaneous shaping and foaming by extrusion without being accompanied by the above described disadvantages and problems in the conventional methods.
The present invention provides a method of making shaped foam articles of a PVC resin which comprises: (a) blending 100 parts by weight of a polyvinyl chloride-based resin with 0.5 to 30 parts by weight of an acrylic resin and at least 10 parts by weight of an inorganic filler to form a resin composition; (b) introducing the resin composition into an extruder; (c) introducing the resin composition into an extruder; (c) heating the resin composition in the extruder; (d) pressurizing an organic solvent-type blowing agent into the thus heated resin composition to form a resin composition expandable by foaming; and (e) extruding the expandable resin composition out of the extruder machine to cause expansion of the composition by foaming.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The PVC resins usable as the base material in the inventive method include not only homopolymeric polyvinyl chloride resins but also various types of copolymers, graft-copolymers, polymer blends and the like provided that polyvinyl chloride or vinyl moiety is the major constituent. The comonomers copolymerizable with vinyl chloride to form a copolymer or graftcopolymer including a vinyl chloride moiety are exemplified by vinyl acetate, vinylidene chloride, acrylic and methacrylic acids and esters thereof, acrylonitrile, methacrylonitrile, maleic acid and esters and an hydroxide thereof, furmaric acid and esters thereof, olefins such as ethylene and propylene, vinyl ethers and the like used either alone or a mixture of two or more.Also, the resins useful as the components of the above mentioned polymer blends include conventional polymeric materials having good compatibility with PVC resins such as polyvinylidene chloride, ethylene-vinyl acetate copolymers, ABS resins, MBS resins, chlorinated polyethylenes, synthetic rubbers including NBR, SBR and the like, and others.
The acrylic resin used as the second component in the resin composition is employed to retain the gas of the blowing agent as it is evolved in the resin composition in the course of foaming by preventing outward dissipation of the gas and to obtain desirable shaped foam articles as the final product with a high expansion ratio by accelerating gelation of the PVC resin and by increasing or adjusting the melt viscosity of the resin in an appropriate range and to prevent coalescence of the cells at elevated temperatures or shrinking of the cells once formed. This component gives a remarkable effect particularly when used in combination with the third component, i.e. the inorganic filler, leading to formation of shaped foam articles with favorable appearance and a fine and uniform cellular structure.
In order to fully attain the above effects, the acrylic resins are selected preferably from those capable of accelerating uniform gelation of the PVC resin, adequeately increasing the melt viscosity of the resin, giving rubber elasticity to the resin and upgrading the tensile strength or elongation of the PVC resin at elevated temperatures. In this regard, the acrylic resin should preferably have reduced viscosity of at least 3.0 dl/g as measured at 20"C in a chloroform solution of 0.1 9/100 ml concentration.
Preferred acrylic resins used with these objects are exemplified by methyl methacrylate polymers, copolymers containing methyl methacrylate as the major constituent such as copolymers prepared from methyl methacrylate and one or more of acrylic acid esters and copolymers containing other monomers copolymerizable therewith.
Exemplary of the above mentioned acrylic acid esters are methyl acrylate, ethyl acrylate, nbutyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate and the like, and exemplary of the monomers copolymerizable with them are styrene, unsaturated nitriles, vinyl esters, and methacrylic acid esters other than methyl methacrylate such as ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate and the like.
Further, in the case where the PVC resin as the principal component of the resin composition has a relatively high degree of polymerization, the degree of polymerization of the acrylic resin should preferably be high enough correspondingly. The amount of the acrylic resin should be in the range from 0.5 to 30 parts by weight or, preferably, from 3 to 20 parts by weight per 100 parts by weight of the PVC resin since the above-mentioned desirable effects cannot be obtained when the amount of the acrylic resin in the resin composition is smaller than 0.5 part by weight and, on the other hand, no particular additional advantages effect can be obtained by the use of an excessive amount thereof.On the contrary, the flame retardancy inherent to the PVC resin would be reduced in the cases of adding the acrylic resin in an amount larger than 30 parts by weight per 100 parts by weight of the PVC resin.
Examples of the inorganic filler used in the resin composition are, for instance, calcium carbonate, magnesium carbonate, barium carbonate, clay, bentonite, mica, talc, asbestos, wollastonite, kaolin, pyrophylite, magnesium silicate, calcium silicate, pumice powder, quartz sand, silica, titanium dioxide, antimony oxides, zinc oxide, alumina, hydrated alumina, magnesium hydroxide, calcium hydroxide, baryta, gypsum, powders and whiskers of metals such as aluminium, iron and copper, glass flakes, glass microballoons, glass fibers, carbon black, graphite, molybendum disulfide, tungsten disulfide, barium ferrite, feldspar and the like. It is optional that some of the above named fillers may be subjected to a surface treatment prior to use.
Several advantages are obtained by the addition of a sufficiently large amount of these inorganic fillers to the resin composition including: (1) an economical advantage by virtue of the increased amount of the resin composition, i.e.
reduction in the cost per unit weight of the composition, by the addition of a relatively inexpensive inorganic filler; (2) improvement in the thermal resistance of the foamed products; (3) electrical characteristics imparted to the products such as an improvement in the electric insulation or increase in the electric conductivity according to the electric property of the filler; (4) increased flame retardancy; (5) shortened aging time; (6) controllability of the specific gravity of the products; (7) improvement in the weathering resistance; (8) improvement in the solvent resistance, (9) finer cell structure; (10) magnetic properties obtained by use of a magentic filler; and (11) increase inthe radiation shielding.
It should be noted, however, that addition of a large amount of fillers is sometimes disadvantageous in the case of extrusion foaming due to the trend toward decreased workability or, in other words, premature foaming already in the die, leading to difficulty in obtaining a foamed article of desired form. Further, several disadvantages may be induced along with the increase in the overall specific gravity of the resin composition as a consequence of the generally high specific gravities of inorganic fillers though with several exceptions. They are, for example, difficulty in manufacturing shaped foam articles with a low specific gravity, difficulty in obtaining a shaped foam article with a high volume fraction occupied by closed cells and decreased uniformity of the cell structure.In some cases, difficulties are caused in the step of the extrusion per se because of the incomplete gelation of the resin composition in the extruder machine and unstable condition in the injection of the organic solvent-type blowing agent.
The present invention has resulted from the extensive investigations by the inventors directed to obtain one or more of the above mentioned advantages (1) to (11) by overcoming these difficulties. The method according to the present invention is capable of providing shaped foam articles of a PVC resin having improved characteristics to satisfy requirements such as thermal resistance, electric properties, flame retardancy, weathering resistance, solvent resistance and the like, having a freely controllable specific gravity in bulk and having fine and uniform cellular structure composed of closed cells by incorporating an inorganic filler having an average particle diameter of at least 0.05 jum but not exceeding 500 ,zm or, preferably, 250 ym.
The use of an inorganic filler having an average particle diameter smaller than 0.05 ym may result in a generally coarser and less uniform cellular structure, markedly decreased volume fraction of the closed cells and dangers of premature foaming in the die in the course of extrusion for simultaneous foaming and shaping to cause remarkable deterioration of the moldability. On the other hand, the use of an inorganic filler having an average particle diameter of 500 ,um or larger may result in a coarser and less uniform cell structure due to lack of the foam-conditioning and cell-sub-dividing effect since filler particles having a diameter larger than the thickness of the partition walls in the cell structure may fall off into the voids of cell pores.
Falling of the filler particles off the cell walls is also the reason for the effect of improvements insufficiently obtained not in proportion to the amount of the added filler.
The required amount of the inorganic filler added in the resin composition should be at least 10 parts by weight or, preferably, at least 20 parts by weight per 100 parts by weight of the
PVC resin. This is because the intended effect of improvements for the characteristics of the foamed products would not be obtained and the effect of cost reduction by extending of quantity can hardly be obtained when the amount of the inorganic filler is 10 parts by weight or smaller.
Use of some additives other than the above described essential components is optional provided that the amounts thereof in the resin composition are limited so as to to decrease the advantageous effects to be obtained according to the present invention. The additives are selected from the conventionally used ones in the compositions comprising a PVC resin such as stabilizers, lubricants, plasticizers, modifying agents, foam conditioning agents, ultraviolet absorbers, antioxidants, antisatic agents and the like.
On the other hand, the blowing agent used in the present invention is selected preferably from aliphatic hydrocarbons and halogenated aliphatic hydrocarbons having a boiling point of 90"C or lower and they are used either alone or as a mixture of two kinds or more according to need. Mixtures of one or more of the above mentioned organic solvents with one or more of organic compounds having compatibility with the PVC resin, such as those selected from aromatic hydrocarbons, halogneated aromatic hydrocarbons, alcoholic compounds, ether compounds, ketone compounds and ester compounds having a boiling point of 200"C or lower, may be used.
When an aliphatic hydrocarbon or halogenated aliphatic hydrocarbon having a boiling point of 90"C or lower and an organic compound having a boiling point of 200"C or lower and compatible with the PVC resin are used in combination, the weight ratio of the former to the latter should be in the range from 100:1 to 100:50 or, preferably 100:5 to 100:30,
The amount of the organic solvent-type blowing agent to be pressurized into the heated resin composition should be determined according to the desired ratio of expansion or bulk density of the shaped foam articles as the final products and, in general, the amount is preferably in the range from 1 to 30 parts by weight per 100 parts by weight of the PVC resin.
In the method of the present invention, a PVC resin composition or a PVC resin compound is first prepared as the intermediate material by mixing a PVC resin, acrylic resin and inorganic filler together with or without other optional additives by use of a suitable mixing machine such as a supermixer and the like, the resin composition thus prepared is introduced into an extruder machine, and then the organic solvent-type blowing agent is pressurized and injected into the resin composition heated in the extruder at the intermediate position of the cylinder. The resin composition should preferably be in an at least partly gelled condition when it is under injection of the blowing agent. The injection of the blowing agent under pressurization is carried out conveniently using a tandem-type plunger pump.The extruder machine may be either a single machine or a tandem-machine composed of two extruder machines connected in tandem.
Although the optimum operating conditions in the extrusion-shaping of foamed articles should be determined in each case in consideration of the nature of the resin composition as the feed to the extruder machine, the kind of organic solvent-type blowing agent and the intended ratio of expansion of the foam products.Generally speaking, a preferred process of simultaneous foaming and shaping is that heating of the resin composition is carried out in the cylinder of the extruder under such a temperature condition that complete gelation of the resin composition is achieved, then a predetermined amount of the organic solvent-type blowing agent is injected under pressurization into the resin composition in the gelled condition followed by lowering of the temperature uniformly throughout the mass to a temperature suitable for extrusion and the composition is extruded into an open atmosphere or into a chamber under a reduced pressure out of a die.
When the temperature of the resin composition is excessively high after the injection of the organic solvent-type blowing agent under pressurization, undesirable phenomena may be caused including gas leakage, shrinkage and coarsening of the cell sizes along with irregularity in the cell configuration and less uniform structure, and formation of open cells occupying a considerably large volume fraction of the foam products. On the other hand, an excessively low resin temperature at the moment of extrusion may cause higher viscosity of the resin composition and the foaming would become incomplete due to the decrease of the foaming pressure by the blowing agent.Accordingly, the desirable operating condition is such that the organic solvent-type blowing agent is fully dispersed throughout the mass of the resin composition during passage through the cooling zone of the extruder where the temperature of the resin composition is uniformly decreased to a temperature suitable for extrusion so as to facilitate complete foaming and shaping by extrusion out of the die.
in accordance with the method of the present invention, shaped articles of high degree of expansion having an extremely fine and uniform cellular structure can be continuously obtained in the form of a plate, sheet, rod, tube or the like corresponding to the cross section of the die of the extruder machine.
EXAMPLE (Experiments No. 1 to No. 10).
Resin compositions were prepared each by blending in a supermixer 100 parts by weight of one of the PVC resins having various degrees of polymerization as shown in the table, 4 parts by weight of a lead-containing stabilizer, 1 part by weight of calcium stearate, 1 part by weight of talc, 10 parts by weight of an acrylic copolymer having a reduced viscosity of 11.5 dl/g and prepared by the copolymerization of 80% by weight of Methyl methacrylate and 20% by weight of n-butyl acrylate and one of the inorganic fillers of the type indicated in the table in an amount also indicated in the same table.
Each of the resin compositions thus prepared was subjected to extrusion for shaping and foaming into a form of a plate using a tandem-type extruder composed of two conjunct machines as described below.
The first extruder with a caliber of 50 mm and L/D = 30 was designed so that an organicsolvent type blowing agent could be injected under pressurization from an injection port provided on the cylinder thereof. The second extruder has a caliber of 65 mm and L/D = 28 and was connected to the front end of the first extruder, and a die of 4 mm thickness and 45 mm width was mounted on the front end thereof
Temperature and other conditions in the first extruder
Temperature of the cylinder: 1 C 90 to 1 20 C 2C 120to180'C 3C 150 to 170'C 4C 150to170'C Temperature of the connecting duct: 1 50 to 1 70 C Injection pressure of the organic blowing agent: shown in the table
Rate of revolution: 50 r.p.m.
Temperature and other conditions in the second extruder
Temperature of the cylinder: 1C 145 to 160'C 2C 135to150'C 3C 125to135'C Temperature of the die: 1 20 to 1 35 C Rate of revolution: 1 5 to 18 r.p.m.
Pressure at the die: shown in table
Composition of the organic solvent-type blowing agent
A: a 70:30 by weight mixture of trichlorotrifluoromethane and butane B a 70: 30:1 5 by weight mixture of trichlorotrifluoromethane, methyl chloride and xylene
Selection of either A or B above is indicated in the table using the respective symbols.
Several foam articles in plate form were prepared by extrusion for simultaneous foaming and shaping at an extruding rate of approximately 35 to 40 kg/hour under the above described condition and examinations were made of the density in kg/m3, condition of the cellular structure, volume fraction of the closed cells, thermal deformation by heating, and solvent resistance thereof to give the results shown in the table.
The condition of the cellular structure was graded in four grades A, B, C and D according to the following criteria.
A: Fine and uniform cellular structure with excellent appearance in which the diameter of cells was 1000 ,um or smaller.
B: Less uniform cellular structure with cells of the diameters including both larger and smaller ones than 1000 ssm.
C: Coarser but relatively uniform cell structure with a uniform cell diameter of 1000 ,um or larger.
D: Coarse and poorly uniform cellular structure with a cell diameter of 1000 ym or larger.
Determination of the volume fraction of closed cells
The volume fraction of closed cells is the volume ratio in % of the volume of the closed cells which do not communicate with ambience of the foamed article to the overall cell volume and calculated by the following equation: AV-W/d Volume fraction of closed cells =
V in which V: bulk volume of the test piece
AV: true volume of the test piece
W: weight of the test piece, and
d: density of the plastic material composing the test piece.
In practice, five test pieces, each 20 mm by 20 mm by 35 mm, were prepared in each of the experiments and the value of AV was determined for each of the test pieces using a Beckman air-comparator gravimeter from which the volume fraction of the closed cells was calculated using the above equation. The values for the five test pieces were averaged and shown in the table.
Thermal deformation
Three test pieces each having dimensions of 25 mm by 100 mm by 100 mm were prepared by cutting a foamed board shaped and expanded by extrusion and aged at 50"C for 18 hours followed by the measurement of the dimensions in three directions. Then the test pieces were heated at 70"C for 1 8 hours followed by the second measurement of the dimensions in three directions. The values of % shinkage for the three directions were averaged for each test piece and the thus averaged values of % shrinkage were further averaged for the three test pieces.
Solvent resistance
The degree of sinking of the foams in the FRP backing test was measured as a measure of the solvent resistance. A test piece having dimensions of 30 mm by 300 mm by 300 mm was prepared by cutting the sample under test and primed with a resin mixture of an unsaturated polyester and a curing catalyst therefor described below by use of a roller applicator followed by overlaying of three sheets of glass fiber mats and coated again with the resin mixture using the roller applicator. The above application steps were carried out at an ambient temperature of 20 to 23"C so that the drying time was about 1 hour. The extent of sinking of the test piece was examined 24 hours after the coating with the resin mixture.
Unsaturated polyester: Rigolack 1 58 BQT containing 45% by weight of styrene, a product by
Showa High Polymer Co.
Curing catalyst: Permek N, a methyl ethyl ketone peroxide product by Nippon Yushi Co.
Resin mixture: 100 parts by weight of the above mentioned unsaturated polyester admixed with 0.5 part by weight of the curing catalyst.
Glass fiber mat: a chopped strand mat MC-450A manufactured by Nitto Spinning Co., Ltd. Table
Experiment No. 1 2 3 4 5 6 7 8 9 10
Average degree of polymerization of polyvinyl chloride resin 600 710 810 810 1280 980 710 810 1050 1220
Type*) I II III IV I V VI I III
Inorganic Average particle diamefiller ter, m 1.2 0.5 2.9 40 240 0.07 0.02 540 2
Amount added, parts 80 50 30 50 30 60 60 40 5
Blowing Type A B B B A B B A B A agent Amount of injection. % 8.5 9.3 9.8 9.7 8.2 7.4 7.3 8.1 8.2 7.4
Bulk density of foamed body, kg/m 45 43 37 35 45 39 33 49 49 42
Volume fraction of closed cells, % 83.9 85.8 91.3 88.2 87.2 82.3 38.5 79.3 72.9 81.3
Thermal deformation at 70 C, % 0.4 0.3 0.2 0.5 0.3 0.4 13.5 4.8 11.3 4.1
Solvent resistance, mm 0.4 0.2 0.4 0.6 0.1 0.3 3.2 4.5 3.0 3.0
Condition of cellular structure A A A A A A B C D D
Remarks **) a b *) I: calcium carbonate; II: -rutile-type titanium dioxide; III: clay; IV: fine grain mica; V: surface-treated calcium carbonate; VI: silicic anhydride **) outstandingly excellent workability in shaping; b: very poor workability in shaping with premature foaming in the die
Claims (11)
1. A method for making a shaped foam article of a polyvinyl chloride-based resin which comprises: (a) blending 100 parts by weight of a polyvinyl chloride-based resin with 0.5 to 30 parts by weight of an acrylic resin and at least 10 parts by weight of an inorganic filler to form a resin composition; (b) introducing the resin composition into an extruder; (c) heating the resin composition in the extruder; (d) pressurizing an organic solvent-type blowing agent into the thus heated resin composition to form a resin composition expandable by foaming; and (e) extruding the expandable resin composition out of the extruder machine to cause expansion of the composition by foaming.
2. The method as claimed in claim 1 wherein the inorganic filler has an average particle diameter in the range from 0.05 ym to 500 jbm.
3. The method as claimed in claim 2 wherein the inorganic filler has an average particle diameter in the range from 0.05 ym to 250 , zm.
4. The method as claimed in claim 1, 2 or 3 wherein the polvinyl chloride-based resin is selected from homopolymeric polyvinyl chloride resins and copolymers, graft-copolymers and polymer blends of which the major polymeric constituent is vinyl chloride moieties.
5. The method as claimed in claim 4 wherein the copolymer is composed of vinyl chloride units and monomeric units derived from a comonomer selected from vinyl acetate, vinylidene chloride, acrylic acid and esters thereof, acrylonitrile, methacrylonitrile, maleic acid and esters and anhydride thereof, fumaric acid and esters thereof, olefins and vinyl ethers.
6. The method as claimed in any preceding claim wherein the acrylic resin is selected from polymethyl methacrylate, copolymers of methyl methacrylate and an ester of acrylic acid and copolymers of methyl methacrylate, an acrylic acid ester and a third comonomer copolymerizable therewith.
7. The method as claimed in claim 6 wherein the acrylic acid ester is selected from n-butyl acrylate, isobutyl acrylate and 2-ethylhexyl acrylate.
8. The method as claimed in claim 6 wherein the comonomer copolymerizable with methyl methacrylate and the acrylic acid ester is selected from unsaturated nitriles, vinyl esters, ethyl methacrylate, n-butyl methacrylate and 2-ethylhexyl methacrylate.
9. The method as claimed in any preceding claim wherein the inorganic filler is selected from calcium carbonate, magnesium carbonate, barium carbonate, clay, bentonite, mica, talc, asbestos, wollastonite, kaolin, pyrophylite, magnesium silicate, calcium silicate, pumice powder, quartz sand, silica, titanium dioxide, antimony oxides, zinc oxide, alumina, hydrated alumina, magnesium hydroxide, calcium hydroxide, baryta, gypsum, aluminum powder, iron powder, copper powder, whisker, glass flakes, glass microballoons, glass fibers carbon black, graphite, molybdenum disulfide, tungsten disulfide, barrium ferrite and feldspar.
10. A shaped foam article of a polyvinyl chloride-based resin having a bulk density of 50 kg/m3 or smaller, in which the volume fraction of the closed cells is at least 80%, and prepared by a method comprising: (a) blending 100 parts by weight of a polyvinyl chloride-based resin with 0.5 to 30 parts by weight of an acrylic resin and at least 10 parts by weight of an inorganic filler to form a resin composition; (b) introducing the resin composition into an extruder; (c) heating the resin composition in the extruder; (d) pressurizing an organic solvent-type blowing agent into the thus heated resin composition to form a resin composition expandable by foaming; and (e) extruding the expandable resin composition out of the extruder machine to cause expansion of the composition by foaming.
11. An article according to Claim 10, substantially as described in any of the Experiments.
1 2. A shaped foam article of a polyvinyl chloride-based resin when prepared by a method according to any one of Claims 1-9.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58065111A JPS59190836A (en) | 1983-04-13 | 1983-04-13 | Manufacture of expanded vinyl chloride resin molding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2139629A true GB2139629A (en) | 1984-11-14 |
| GB2139629B GB2139629B (en) | 1986-11-12 |
Family
ID=13277452
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08409660A Expired GB2139629B (en) | 1983-04-13 | 1984-04-13 | Method for making shaped foam articles of a vinyl chloride resin |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JPS59190836A (en) |
| GB (1) | GB2139629B (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0214634A2 (en) * | 1985-09-09 | 1987-03-18 | Kanegafuchi Kagaku Kogyo Kabushiki Kaisha | Process for preparing mold-formed expanded articles of vinyl chloride resin compositions |
| EP0215403A2 (en) * | 1985-09-09 | 1987-03-25 | Kanegafuchi Kagaku Kogyo Kabushiki Kaisha | Expandable particles of vinyl chloride resin composition for beads-foaming |
| EP0308200A2 (en) * | 1987-09-18 | 1989-03-22 | Kyowa Leather Cloth Co., Ltd. | Method for producing a laminated material |
| DE19746006A1 (en) * | 1997-10-20 | 1999-04-22 | Agomer Gmbh | Foamable polyvinyl halide resin compositions, use of polymers therein as processing aids, moldings produced therefrom |
| CH691046A5 (en) * | 1996-06-05 | 2001-04-12 | Veka Ag | Thermoplastic material for use in baths and whirlpool tubs, cars, wall coverings and pay phone hoods consists at least partly of poly (vinyl chloride) foam |
| EP1097963A1 (en) * | 1998-02-24 | 2001-05-09 | Mitsubishi Rayon Co., Ltd. | Processing aid for foam molding and vinyl chloride resin composition containing the same |
| EP1597306A1 (en) * | 2003-02-19 | 2005-11-23 | LG Chem Ltd. | Polyvinyl chloride foams |
| EP1854835A1 (en) * | 2001-11-02 | 2007-11-14 | Veka, Inc. | A method of making extruded shapes |
| US20110207839A1 (en) * | 2008-10-31 | 2011-08-25 | Tessenderlo Chemie N.V./S.A. | Foamed PVC profiles with a high mineral filler content and their uses |
| WO2011142681A1 (en) * | 2010-05-10 | 2011-11-17 | Termo Organika Sp. Z.O.O. | Agent for modification of expandable and expanded materials and expandable and expanded materials so modified |
| CN109485907A (en) * | 2018-10-04 | 2019-03-19 | 南京万和新材料有限公司 | A kind of rubber-plastic foamed heat-insulating material |
| CN113150470A (en) * | 2021-05-17 | 2021-07-23 | 湖北合扬科技有限公司 | Low-density high-extrusion-rate PVC fireproof sealing strip and preparation method thereof |
| CN113788980A (en) * | 2021-08-31 | 2021-12-14 | 暨南大学 | Pre-swelling continuous extrusion foaming polylactic acid material and preparation method and application thereof |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3572504D1 (en) * | 1984-06-14 | 1989-09-28 | Kanegafuchi Chemical Ind | Process for preparing foamed article of vinyl chloride resin containing a large amount of inorganic particles |
| JPH0366389U (en) * | 1989-10-30 | 1991-06-27 |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2034322A (en) * | 1978-11-10 | 1980-06-04 | Shinetsu Chemical Co | Expandable compositions for polyvinyl chloride resin foams |
| EP0039118A1 (en) * | 1980-04-26 | 1981-11-04 | Stamicarbon B.V. | Rigid polyvinyl chloride foam |
| GB2110216A (en) * | 1981-11-16 | 1983-06-15 | Shinetsu Chemical Co | Preparation of a foamed body of a vinyl chloride-based resin composition |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5731539A (en) * | 1980-08-04 | 1982-02-20 | Shin Etsu Chem Co Ltd | Manufacture of vinyl chloride resin foamed molding |
-
1983
- 1983-04-13 JP JP58065111A patent/JPS59190836A/en active Pending
-
1984
- 1984-04-13 GB GB08409660A patent/GB2139629B/en not_active Expired
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2034322A (en) * | 1978-11-10 | 1980-06-04 | Shinetsu Chemical Co | Expandable compositions for polyvinyl chloride resin foams |
| EP0039118A1 (en) * | 1980-04-26 | 1981-11-04 | Stamicarbon B.V. | Rigid polyvinyl chloride foam |
| EP0039117A1 (en) * | 1980-04-26 | 1981-11-04 | Stamicarbon B.V. | Rigid polyvinyl chloride foam |
| EP0040443A2 (en) * | 1980-04-26 | 1981-11-25 | Stamicarbon B.V. | Method for the preparation of rigid polyvinyl chloride foams |
| GB2110216A (en) * | 1981-11-16 | 1983-06-15 | Shinetsu Chemical Co | Preparation of a foamed body of a vinyl chloride-based resin composition |
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0214634A2 (en) * | 1985-09-09 | 1987-03-18 | Kanegafuchi Kagaku Kogyo Kabushiki Kaisha | Process for preparing mold-formed expanded articles of vinyl chloride resin compositions |
| EP0215403A2 (en) * | 1985-09-09 | 1987-03-25 | Kanegafuchi Kagaku Kogyo Kabushiki Kaisha | Expandable particles of vinyl chloride resin composition for beads-foaming |
| EP0214634A3 (en) * | 1985-09-09 | 1988-05-18 | Kanegafuchi Kagaku Kogyo Kabushiki Kaisha | Process for preparing expandable particles of vinyl chloride resin composition |
| EP0215403A3 (en) * | 1985-09-09 | 1988-05-18 | Kanegafuchi Kagaku Kogyo Kabushiki Kaisha | Expandable particles of vinyl chloride resin composition for beads-foaming |
| EP0308200A2 (en) * | 1987-09-18 | 1989-03-22 | Kyowa Leather Cloth Co., Ltd. | Method for producing a laminated material |
| EP0308200A3 (en) * | 1987-09-18 | 1990-08-01 | Kyowa Leather Cloth | Method for producing a laminated material |
| US4986860A (en) * | 1987-09-18 | 1991-01-22 | Kyowa Leather Cloth Co., Ltd. | Method for producing a laminated material |
| CH691046A5 (en) * | 1996-06-05 | 2001-04-12 | Veka Ag | Thermoplastic material for use in baths and whirlpool tubs, cars, wall coverings and pay phone hoods consists at least partly of poly (vinyl chloride) foam |
| DE19746006A1 (en) * | 1997-10-20 | 1999-04-22 | Agomer Gmbh | Foamable polyvinyl halide resin compositions, use of polymers therein as processing aids, moldings produced therefrom |
| EP0911358A1 (en) * | 1997-10-20 | 1999-04-28 | Agomer Gesellschaft mit beschränkter Haftung | Foamable polyvinylhalide resin compositions, use of polymers therein as processing aids and mouldings obtained therefrom |
| EP1097963A1 (en) * | 1998-02-24 | 2001-05-09 | Mitsubishi Rayon Co., Ltd. | Processing aid for foam molding and vinyl chloride resin composition containing the same |
| EP1097963A4 (en) * | 1998-02-24 | 2003-08-06 | Mitsubishi Rayon Co | Processing aid for foam molding and vinyl chloride resin composition containing the same |
| EP1854835A1 (en) * | 2001-11-02 | 2007-11-14 | Veka, Inc. | A method of making extruded shapes |
| EP1597306A1 (en) * | 2003-02-19 | 2005-11-23 | LG Chem Ltd. | Polyvinyl chloride foams |
| EP1597306A4 (en) * | 2003-02-19 | 2007-06-06 | Lg Chemical Ltd | Polyvinyl chloride foams |
| US20110207839A1 (en) * | 2008-10-31 | 2011-08-25 | Tessenderlo Chemie N.V./S.A. | Foamed PVC profiles with a high mineral filler content and their uses |
| WO2011142681A1 (en) * | 2010-05-10 | 2011-11-17 | Termo Organika Sp. Z.O.O. | Agent for modification of expandable and expanded materials and expandable and expanded materials so modified |
| CN109485907A (en) * | 2018-10-04 | 2019-03-19 | 南京万和新材料有限公司 | A kind of rubber-plastic foamed heat-insulating material |
| CN113150470A (en) * | 2021-05-17 | 2021-07-23 | 湖北合扬科技有限公司 | Low-density high-extrusion-rate PVC fireproof sealing strip and preparation method thereof |
| CN113788980A (en) * | 2021-08-31 | 2021-12-14 | 暨南大学 | Pre-swelling continuous extrusion foaming polylactic acid material and preparation method and application thereof |
| CN113788980B (en) * | 2021-08-31 | 2022-10-21 | 暨南大学 | Pre-swelling continuous extrusion foaming polylactic acid material and preparation method and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2139629B (en) | 1986-11-12 |
| JPS59190836A (en) | 1984-10-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19930413 |