Classifications

• • 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
  • B29C67/00—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00
  • B29C67/24—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00 characterised by the choice of material
  • B29C67/242—Moulding mineral aggregates bonded with resin, e.g. resin concrete
  • B29C67/243—Moulding mineral aggregates bonded with resin, e.g. resin concrete for making articles of definite length
• • 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
  • B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
  • B29C43/003—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor characterised by the choice of material
• • 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
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/02—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising combinations of reinforcements, e.g. non-specified reinforcements, fibrous reinforcing inserts and fillers, e.g. particulate fillers, incorporated in matrix material, forming one or more layers and with or without non-reinforced or non-filled layers
• • 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
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/02—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising combinations of reinforcements, e.g. non-specified reinforcements, fibrous reinforcing inserts and fillers, e.g. particulate fillers, incorporated in matrix material, forming one or more layers and with or without non-reinforced or non-filled layers
  • B29C70/021—Combinations of fibrous reinforcement and non-fibrous material
  • B29C70/025—Combinations of fibrous reinforcement and non-fibrous material with particular filler
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K13/00—Use of mixtures of ingredients not covered by one single of the preceding main groups, each of these compounds being essential
  • C08K13/04—Ingredients characterised by their shape and organic or inorganic ingredients
• • 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
  • B29K2063/00—Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
• • 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
  • B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
  • B29K2067/06—Unsaturated polyesters
• • 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
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
  • B29K2105/08—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts of continuous length, e.g. cords, rovings, mats, fabrics, strands or yarns
  • B29K2105/0854—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts of continuous length, e.g. cords, rovings, mats, fabrics, strands or yarns in the form of a non-woven mat
• • 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
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
  • B29K2105/12—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts of short lengths, e.g. chopped filaments, staple fibres or bristles
• • 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
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
  • B29K2105/16—Fillers
• • 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
  • B29K2309/00—Use of inorganic materials not provided for in groups B29K2303/00 - B29K2307/00, as reinforcement
  • B29K2309/08—Glass

Definitions

• the invention relates to a process for producing molded parts by mixing unsaturated polyester resin, mineral fillers and magnesium oxide, thickening this mixture in the presence of glass fibers and pressing parts of the thickened mass at elevated temperature.
• SMC 'sheet molding compound'
• This mixture is allowed to thicken in the presence of a glass fiber layer between the polyethylene film. Then you fill a mold with the mass or with parts of it together with the glass fiber layer and the whole is pressed at elevated temperature. The processing of masses of this type is quite labor intensive. The required high glass fiber content and the resin also make the molded parts relatively expensive.
• a third mass called the 'bulk molding compound' (BMC)
• BMC 'bulk molding compound'
• the object of the present invention is now to produce molded parts from a mixture of the composition mentioned at the outset which is easier to process, is cheaper and has an equally good or even better modulus of elasticity than the aforementioned mixtures.
• the mixture contains 80 to 95% by weight of inorganic fillers with a grain size mainly between 0 and 500 microns, 1 to 5% by weight of glass fibers, based on the mixture as a whole. at least 3/4 of which have a length of less than 15 mm and are mainly present as random threads and contain 0.5 to 5% by weight of a alkali metal oxide, preferably magnesium oxide, based on the unsaturated polyester resin, which mixture is thickened until it is compact and almost air-free.
• a alkali metal oxide preferably magnesium oxide
• the invention is based on the knowledge that it is possible to produce a molding compound with a very high filler content, which can be pressed very well into thin-walled molded parts of any shape and good quality.
• the prerequisite for this is that the glass fibers are available in a well-specified form and quantity.
• the low content of resin and glass fibers makes the cost price of the to produce molded parts lower than when using the known mixtures.
• a further requirement for the method according to the invention is that the mass is compact and almost free of air before it is pressed.
• the unsaturated polyester resin can be any suitable polyhydric alcohol and polyhydric reaction product Acids or acid-forming anhydrides.
• alcohols propylene glycol, ethylene glycol, pentanediol, butanediol, butylene glycol and dipropylene glycol can be mentioned.
• acids are maleic anhydride, phthalic anhydride, isophthalic anhydride, adipic acid and the like. Like. Common.
• the unsaturated polyester resin is usually cross-linked.
• Unsaturated compounds such as styrene, methyl methacrylate, vinyl acetate and diallyl phthalate are suitable for this purpose.
• the usual peroxides such as benzoyl peroxide or tertiary butyl perbenzoate can be used as a catalyst in this crosslinking.
• a product such as hydrogenated bisphenol A plus catalyst, known commercially as 'Synolite 373', is also useful for this purpose.
• the mixture of resin, fillers and glass fibers described above is viscous.
• the mixture is poured into a container or the like and allowed to thicken to a compact, almost air-free molding compound in 1 to 48 hours.
• a compact molding compound With a compact molding compound, a dense mass similar to window putty is indicated, which is so viscous that it almost does not lose a given shape and can be divided into parts by cutting.
• This thickening is based on the effect of the magnesium oxide, which is also mixed in.
• the required amount can be cut off from the thickened mass and placed in the press mold or die, after which the whole is pressed to the desired molded part at elevated temperature. It is of crucial importance that, in contrast to the known molding compounds, an air-free, compact molding compound is obtained.
• Temperature and pressure are not critical when pressing the mass and are caused, among other things, by the wall thickness of the desired molded part in relation to the optimum pressing time and the catalyst. Usual temperatures are 100 to 250 ° C, usual pressures are between 3 and 20 MPa.
• the pressing time is usually between and 30 minutes and preferably approx. 1 up to 6 minutes.
• Molded parts produced using the method described above can be provided with a hard and or decorative surface layer during or shortly after the pressing.
• the molded part which is still hot and not yet fully cured, can be used, for example, shortly after pressing with a powdered one to treat.
• Epoxy resins containing free hydroxyl groups such as methylol or phenol groups, or unsaturated polyester resins and mixtures of an epoxy and a polyester resin are suitable for this purpose.
• the free hydroxyl groups can also not fully cured molded part in this way cause a three-dimensional crosslinking, whereby good adhesion between the surface layer and molded part is achieved.
• This treatment method is preferably used if the molded part still has a temperature of at least 150 ° C. and preferably of 175-200 ° C.
• An advantage here is that the molded part according to the invention has a high heat content thanks to its high content of inorganic fillers.
• Treatment with powdered resin can consist of spraying, electrostatic atomization, and dipping into a fluid bed of the powder. In general, 50 to 300 g of powder are applied per m 2 .
• One of the two glass fleece can also be printed with a motif beforehand, preferably with the help of a colored or pigmented resin. Combinations of both methods are also possible.
• molded parts can also be provided with a decoration in the manner described in Dutch patent application 7305807.
• An unsaturated polyester resin is a polycondensation product from:
• a part cut from this mass is then pressed in a die 1'30 "at a temperature of 200 C and a pressure of 150 kg / cm 2 (15 MPa) to a plate with a thickness of approx. 8 mm.
• the E -Module of this material is approximately 150,000 kg / cm 2 (15 GN / m 2 ) compared to 115,000 kg / cm 2 (11.5 GN / m 2 ) b between 110,000 kg / cm 2 (11 GN / m 2 ) for the commercially available BMC or SMC compounds pressed in the same way.
• the same plate with an untreated surface is exposed to the weather conditions of a sea climate for a long time.
• the surface shows no visible changes.
• the same pressing test is carried out with 0.5 or 6% by weight of glass fibers.
• the plate In the first case the plate is very brittle; in the second case, the mixture cannot be poured out and cannot be converted into an air-free, compact molding compound.
• a molding compound as described above with the same weight ratios of the components, but with long glass fibers is less suitable for pressing into strongly curved, thin-walled molded parts than a molding compound with short, arbitrarily oriented glass fibers. In this case, it turns out that the strength at bent points is less good than when using short fibers. The risk of breakage in strongly curved places is too great to make everyday items from this mass.
• the present invention is not limited to relatively complicated molded parts, but also includes relatively simple molded parts such as tiles or wall panels.
• the modified epoxy resin does not need to be monochromatic, and systematic or arbitrary shades of color are also possible.
• the invention also relates to molded parts whose bodies contain 80 to 95% by weight of inorganic fillers with a grain size mainly between 0 and 500 microns, and a maximum of 5% by weight, based on the total mass, of glass fibers, of which at least 3/4 of a length of less than 15 mm and mainly as threads in an arbitrary distribution, as well as hardened polyester resin containing a magnesium compound.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Composite Materials (AREA)
• Health & Medical Sciences (AREA)
• Structural Engineering (AREA)
• Ceramic Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Casting Or Compression Moulding Of Plastics Or The Like (AREA)
• Reinforced Plastic Materials (AREA)
• Moulding By Coating Moulds (AREA)
• Compositions Of Macromolecular Compounds (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=19828778

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (2)

Citations (7)

• 1977
  • 1977-06-24 NL NLAANVRAGE7706997,A patent/NL186016C/xx not_active IP Right Cessation
• 1978
  • 1978-06-19 DE DE7878200045T patent/DE2862193D1/de not_active Expired
  • 1978-06-19 EP EP78200045A patent/EP0000223B1/fr not_active Expired
  • 1978-06-23 IT IT50016/78A patent/IT1105043B/it active
  • 1978-06-23 JP JP7636678A patent/JPS5411174A/ja active Granted

Patent Citations (7)

Also Published As

Similar Documents

Legal Events