Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
  • C08L67/06—Unsaturated polyesters
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L31/00—Compositions 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 an acyloxy radical of a saturated carboxylic acid, of carbonic acid or of a haloformic acid; Compositions of derivatives of such polymers
  • C08L31/02—Homopolymers or copolymers of esters of monocarboxylic acids

Definitions

• the invention relates to the use of functionalized polyvinyl esters for increasing the surface tension of BMC / SMC moldings.
• Unsaturated polyester resin compositions are frequently used in the production of sheet-like plastic parts. These polyester resins are reaction products of a dicarboxylic acid or a dicarboxylic acid anhydride with a polyol. Such polyester resin compositions also contain a monomer having ethylenically unsaturated groups, generally styrene. Styrene is added to the polyester resin composition to dissolve the polyester and to ensure that the polyester composition is a flowable mass. To reinforce the plastic parts obtained with the polyester resin composition, the polyester resin compositions still contain fiber materials such as glass fiber, carbon fiber or corresponding fiber mats.
• the low-profile additive reduces shrinkage during curing, reduces residual stresses, reduces micro-cracking and facilitates compliance with manufacturing tolerances.
• the low-profile additives are thermoplastics such as polystyrene, polymethyl methacrylate and in particular polyvinyl acetate. Polyvinyl acetates having up to 1% by weight of carboxyl-functional comonomer units are also used. At higher levels of carboxyl functional comonomer units, shrinkage reduction is unsatisfactory.
• Two methods for the production of thermoset moldings from FRP composites are BMC technology (BuIk Molding Compound) and SMC technology (Sheet Molding Compound). In the BMC process, the components of the compound, the styrene polyester resin solution, the low profile additives, the
• reflectors for car headlights are produced with this technology.
• SMC process a paste-like mass of styrenic polyester resin solution, low-profile additive, crosslinking catalyst, filler, mold release agent and, if appropriate, further additives which is applied to a polyamide film is produced analogously to the BMC process.
• fiberglass is sprinkled on this layer, and finally applied another layer of the pasty mass.
• This sheet sandwich is then peeled from the film, cut into pieces and pressed using pressure and temperature to form parts. Molded parts which are produced by means of this technique are for example tailgates of automobiles.
• the invention relates to the use of functionalized polyvinyl ester solid resins as an additive in unsaturated polyester resin compositions for improving the surface tension of moldings obtained therefrom.
• Suitable vinyl ester monomers for the functionalized polyvinyl ester solid resin are vinyl esters of unbranched or branched carboxylic acids having 1 to 18 carbon atoms.
• Preferred vinyl esters are vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate, vinyl pivalate and vinyl esters of C-branched monocarboxylic acids having 5 to 13 carbon atoms, for example VeoVa9 R or VeoValOR (trade name of Shell) or mixtures thereof vinyl ester monomers.
• Particularly preferred is vinyl acetate.
• Suitable comonomers with functional groups are comonomers with carboxylic acid groups, sulfonic acid groups or phosphonic acid groups. Preference is given to ethylenically unsaturated mono- and dicarboxylic acids, vinyl sulfonate and vinyl phosphonate. Particularly preferred are acrylic acid, methacrylic acid, fumaric acid and crotonic acid.
• the proportion of comonomer units with functional groups are comonomers with carboxylic acid groups, sulfonic acid groups or phosphonic acid groups.
• Groups in the polyvinyl ester solid resin is preferably greater than 1 wt .-% up to 10 wt .-%, particularly preferably 3 to 10 wt .-%, each based on the total weight of the solid polyvinyl ester resin.
• solid resins based on vinyl acetate which contain acrylic acid or crotonic acid comonomer units in the abovementioned amounts.
• the functionalized polyvinyl ester solid resins are prepared by the mass, suspension, or preferably solution polymerization process.
• Suitable solvents are, for example, monohydric, aliphatic alcohols having 1 to 6 C atoms, preferably methanol, ethanol, propanol, isopropanol. Particularly preferred are ethanol and isopropanol.
• the reaction is generally carried out under Ruckfluß discipline, generally at a polymerization temperature of 40 0 C to 140 ° C, made to utilize the evaporative cooling to Abbowung the heat of reaction. This can be done at atmospheric pressure as well as under slight overpressure.
• the initiators used are organic peroxides or azo compounds. Suitable examples include diacyl peroxides such as dilauroyl peroxide, peroxo esters such as t-butyl peroxypivalate or t-butyl peroxo-2-ethylhexanoate, or peroxodicarbonates such as diethyl peroxodicarbonate.
• the amount of initiator is generally from 0.01 to 5.0 wt .-%, based on the monomers.
• the initiators can both be submitted and metered. It has been preserved to submit a portion of the required amount of initiator and to meter the rest continuously during the reaction.
• the adjustment of the molecular weight can be carried out in a manner known to the skilled worker by polymerization in the presence of molecular weight regulators.
• Suitable regulators are, for example, alcohols such as ethanol or isopropanol, aldehydes such as acetaldehyde or propionaldehyde, silane-containing regulators such as mercaptosilanes, for example 3-mercaptopropyltrimethoxysilane.
• the polymers it is possible to use a batch process in which all components of the polymerization batch are initially charged in the reactor or by a seim batch process, in which one or more components are initially introduced and the remainder is metered in, or a continuous polymerization is carried out be added, wherein the components are added during the polymerization. If necessary, the dosages can be carried out separately (in terms of space and time).
• a typical formulation for unsaturated polyester resin compositions for the BMC technique and the SMC technique contains 60 to 70 parts by weight unsaturated polyester resin (as a 50 to 75% solution in styrene), 30 to 40 parts by weight low Profile additives or polymethyl methacrylate, 0.5 to 2 parts by weight of initiator such as t-butyl perbenzoate, 150 to 200 parts by weight of filler such as calcium carbonate, 25 to 30 parts by weight of glass fiber, 0.5 to 3 parts by weight of mold release agent such as zinc stea- rat, and optionally other additives, such as pigments, thickeners, flame retardant additives.
• the formulations contain no thickening agents such as basic metal compounds, for example oxides or hydroxides of metals of the 1st to 3rd main group of the PSE.
• the functionalized polyvinyl ester solid resin is used in an amount of 10 to 80% by weight, preferably 50 to 80% by weight, in each case based on the weight of low-profile additive in the formulation. It is expedient to use this additive in styrenic solution.
• the surface tension of moldings based on unsaturated polyester resin compositions should preferably be> 35 N / mm 2 , more preferably> 38 N / mm 2 .
• the surface tension is generally determined with test inks or test pens in accordance with DIN 53364.
• Vac-CS copolymer vinyl acetate-crotonic acid copolymer with 5% by weight crotonic acid

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Macromonomer-Based Addition Polymer (AREA)
• Reinforced Plastic Materials (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 2006
  • 2006-04-27 DE DE102006019676A patent/DE102006019676A1/de not_active Ceased
• 2007
  • 2007-04-19 EP EP07728313A patent/EP2010582A1/de not_active Withdrawn
  • 2007-04-19 US US12/297,772 patent/US20090105406A1/en not_active Abandoned
  • 2007-04-19 CN CNA200780014435XA patent/CN101426825A/zh active Pending
  • 2007-04-19 JP JP2009507041A patent/JP2009534510A/ja not_active Withdrawn
  • 2007-04-19 WO PCT/EP2007/053854 patent/WO2007125045A1/de active Application Filing
  • 2007-04-20 TW TW096113914A patent/TW200740919A/zh unknown

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