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
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/04—Reinforcing macromolecular compounds with loose or coherent fibrous material
  • C08J5/06—Reinforcing macromolecular compounds with loose or coherent fibrous material using pretreated fibrous materials
  • C08J5/08—Reinforcing macromolecular compounds with loose or coherent fibrous material using pretreated fibrous materials glass fibres
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
  • C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
  • C03C25/10—Coating
  • C03C25/24—Coatings containing organic materials
  • C03C25/26—Macromolecular compounds or prepolymers
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
  • C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
  • C03C25/10—Coating
  • C03C25/24—Coatings containing organic materials
  • C03C25/26—Macromolecular compounds or prepolymers
  • C03C25/28—Macromolecular compounds or prepolymers obtained by reactions involving only carbon-to-carbon unsaturated bonds

Definitions

• the invention relates to glass strands coated with a sizing composition intended to reinforce organic materials of the polymer type, the sizing composition used for coating said strands and the composites thus obtained.
• the glass strands used for reinforcement in general are produced industrially from molten glass streaks flowing from the multiple orifices of a die. These threads are drawn mechanically in the form of continuous filaments, then are gathered into basic threads which are then collected, for example by winding on a rotating support. Before their gathering, the filaments are coated with a sizing composition by passing over a suitable device such as coating rollers.
• the sizing composition is essential for several reasons.
• the sizing composition protects the glass filaments from abrasion which occurs when the latter rub at high speed on the various members serving to guide and collect them. It also establishes connections between the filaments which makes it possible to give cohesion to the thread. The yarn being made more intact, its handling, especially during weaving operations, is improved and untimely breaks are avoided.
• the sizing composition promotes the wetting and impregnation of the glass strands by the matrix to be reinforced, which matrix is generally implemented in the form of a more or less fluid resin. The mechanical properties of the final composite are therefore significantly improved.
• the materials to be reinforced can integrate glass strands in different forms: continuous or cut strands, continuous or cut strand mats, fabrics, etc.
• the composites which incorporate cut glass strands can be obtained, inter alia, by the technique of "contact molding” which consists in coating the interior of an open mold, without counter mold, with resin to be reinforced and glass wires of variable length.
• the resin and the cut wires are projected together onto the internal walls of the mold by means of a "gun” comprising an incorporated cutter capable of cutting the wires extracted from one or more windings, generally in the form of rovings, and from a device making it possible to spray the resin, supplied for example by a pneumatic pump.
• This simple and modular process is particularly suitable for unit production or small series of parts based on thermosetting polymers belonging to the family of polyesters or epoxides.
• Another composite manufacturing technique also by molding, is known under the name "LFI" or Long Fiber Injection. It consists in projecting into a mold, simultaneously, wires cut at a high speed (of the order of 300 to 1200 meters per minute) in cycles lasting a few tens of seconds and reactive monomers capable of giving a resin by polymerization, and then applying a counter mold.
• This technique is particularly suitable for the production of polyurethane parts, in particular in the form of foam.
• the quality of the composites obtained by these processes depends largely on the properties provided by the glass strands, and therefore on the size which covers them.
• compositions giving a size which can be easily wetted or impregnated on the surface with the resin in order to ensure close contact between the wires and the resin and thus obtain the expected mechanical reinforcement properties. It is also desired that these compositions are compatible with rapid processing, in particular that the mixture of son / resin or son / monomers which is sprayed onto the mold in the form of overlapping strips can spread evenly. In particular, the subsequent rolling step already mentioned intended to eliminate air bubbles and to ensure a better distribution of the wires in the resin must also be of short duration.
• the sizing composition it is also necessary for the sizing composition to have a certain “incompatibility” with the resin, that is to say that it is not too soluble in the resin so as to avoid the mixture of yarns / resin forms a compact mass which "collapses" by simple gravity.
• This parameter is important when it comes to producing very thick parts requiring to spray a large quantity of mixture into the mold.
• it is sought to reduce the speed of impregnation of the wire with the resin.
• the impregnation speed should not be too low because then the son / resin mixture has poor "conformability", that is to say that it is not able to perfectly match the shape of the mold.
• the criterion of conformability is very important when the mold has a large dimension, from a few meters to several tens of meters. It is just as necessary that the cut strands maintain their integrity and do not “filamentize”, that is to say do not burst by releasing the filaments which constitute them, during projection but also during other treatments than they are brought to undergo such as the rolling / boiling operation already mentioned. It is still essential that the wire can be extracted from the roving without forming loops, without generating tension and by giving as little stuffing as possible so as not to disturb the operation of the cutter. Sized glass strands adapted to these molding techniques are already known.
• glass strands coated with a sizing composition comprising, as tackifying film-forming agents, the combination of at least one low molecular weight polyvinyl acetate A and at least one vinyl acetate copolymer B which is thermally cross-linkable in an A / B weight ratio greater than or equal to 1. These threads have a high rate of impregnation with the resin.
• the glass strands are coated with an essentially aqueous sizing composition which comprises at least one bis-silane A and at least one unsaturated monosilane (B) chosen from vinylsilanes and methyl ( acrylosilanes).
• the glass strands are coated with a sizing product comprising an aqueous mixture based on polyvinyl acetate, a lubricant based on fatty acid, chromic methacrylato chloride and gamma (ethylene diamine) propyltrimethoxysilane.
• a sizing product comprising an aqueous mixture based on polyvinyl acetate, a lubricant based on fatty acid, chromic methacrylato chloride and gamma (ethylene diamine) propyltrimethoxysilane.
• the strands belonging to the first type are coated with a size based on polyvinyl acetate and compounds comprising chromium.
• the object of the present invention is to provide a sizing composition for reinforcing threads, in particular intended for open mold molding, in particular for simultaneous projection molding, or for closed mold, in particular for LFI molding, which does not contain no chromium and which makes it possible to obtain performances equivalent to those of glass strands known for these applications, in particular in terms of speed of impregnation of the strands by the resin, production of fiber and integrity.
• the subject of the invention is glass strands coated with an aqueous sizing composition which comprises, as tackifying film-forming agents, at least one polyvinyl acetate, at least one copolymer of vinyl acetate and of another monomer. unsaturated and at least one epoxy.
• glass strands coated with a sizing composition which comprises ...” is meant not only the glass strands coated with the composition in question as obtained on immediate exit from the organ or sizing organs, but also these same threads after they have undergone one or more other treatments.
• son means the basic son from the gathering under the die of a multitude of filaments, and products derived from these son, including the assemblies of these basic son rovings.
• aqueous sizing composition means a sizing composition in the form of a solution in which the liquid phase consists of 97% by weight of water, preferably 99% and better still 100%, the complement consisting, where appropriate, of one or more essentially organic solvents which can help to dissolve certain constituents of the sizing composition.
• the sizing composition comprises, as tackifying film-forming agents, the mixture of at least one polyvinyl acetate, at least one copolymer of vinyl acetate and of another unsaturated monomer, and at least an epoxy.
• Polyvinyl acetate is important for quickly reaching a high level of resin impregnation of the wires and obtaining good conformability of the wire / resin mixture in the mold.
• the molecular weight of the polyvinyl acetate is generally less than 80,000 g / mol, preferably less than 70,000 g / mol and preferably is between 40,000 and 65,000 g / mol.
• the amount of polyacetate used generally represents 20 to 50% by weight of the solids of the sizing composition, preferably 30 to 40%.
• the copolymer is obtained by co-polymerization of vinyl acetate and another unsaturated monomer, for example a monomer of the olefinic type.
• the monomer is ethylene.
• the copolymer has a lower solubility in the resin than polyvinyl acetate; it therefore contributes to reducing the speed of impregnation of the wires by the resin. By modulating the content of copolymer relative to that of polyvinyl acetate, it is possible to adjust the properties of the final sizing as well as possible.
• the amount of copolymer generally represents 20 to 45% by weight of the solids of the composition, preferably 30 to 40%. When the content is greater than 45%, the conformability is insufficient. When the content is less than 20%, the wire loses its stiffness.
• the weight ratio of polyvinyl acetate to the copolymer varies from 30:70 to 70:30, and better still from 40:60 to 60:40. More preferably, the sum of the contents by weight of polyvinyl acetate and of copolymer represents 50 to 80% by weight of the solid matters of the sizing composition.
• the epoxy promotes the bonding of the filaments, thereby improving the stiffness of the wire which contributes to having a more homogeneous distribution of the wires cut in the resin after spraying into the mold. It also helps limit the formation of fluff.
• the epoxy is generally chosen from resins having a molecular weight greater than 5,000 g / mol, preferably less than 20,000 g / mol. They advantageously have an epoxide index greater than 800 g equivalent, preferably between 1,200 and 2,000, and better still of the order of 1,500 g equivalent.
• epoxy resins resulting from the reaction of epichlorohydrin and an alcohol for example bisphenol A or F, polyethylene glycols, glycerol, pentaerythritol or novolak resins.
• the epoxy results from the reaction of epichlorohydrin and bisphenol A.
• the epoxy is used in combination with another epoxy carrying one or more amine functions which has the role of providing stiffness to the wire without significantly affecting conformability.
• the amount of epoxy generally represents 10 to 20% of the weight of the solids of the sizing composition, preferably 12 to 16%.
• the sizing composition may advantageously comprise one or more other components (hereinafter referred to as "additives").
• the sizing composition can thus comprise one or more lubricating agents in an amount representing 1 to 20% by weight of the solids of the sizing composition.
• the lubricant (s) contribute) to limit the formation of fluff, to increase the stiffness of the wire and to avoid the sticking of the turns on the windings of basic son .
• these agents are chosen from cationic compounds of the polyalkylene irnide type, and ionic compounds of the ester type of fatty acids and of poly (al ylene glycols) poly (oxyalkylene) such as polyethylene glycol monolaurate, or of the amide type d. fatty acids and poly (o yalkylene) such as hydrogenated tallow amides and polyethylene.
• the sizing composition can also comprise at least one coupling agent making it possible to hang the sizing on the surface of the glass filaments.
• the coupling agent is generally chosen from silanes such as gamma-glycidoxypropyltrimethoxysilane, gamma-acryloxypropyltrimethoxysilane, gamma-methacryloxypropyltrimethoxysilane, poly (oxyethylene / oxypropylene) trimet thoxysilane, gamma-amimropyltrioxetane phenyl - aminopropyltrimethoxysilane or slyiylammoélhylarninopropyltriméthoxy-silane, siloxanes, titanates, zirconates and mixtures of these compounds.
• the silanes are chosen.
• the amount of coupling agent generally represents less than 5% by weight of the solids of the sizing composition, preferably is greater than 2% and most often is of the order of 3%. All these additives contribute to the production of reinforcement threads which can be easily manufactured, which maintain good integrity, which can be cut without problem and sprayed into a mold while being slowly impregnated with the resin or the resin precursor monomers. . It is also possible to introduce an anti-static agent such as ethyl chloride in the sizing composition. The amount of this agent generally represents less than 5% of the weight of the solid materials contained in the sizing composition.
• the glass strands coated with the sizing composition in accordance with the invention have a loss on ignition of less than 2.2%, preferably greater than 1.1% and better still between 1.4 and 1.60%.
• the glass strands according to the invention are in the form of windings of basic strands which are subjected to a heat treatment.
• This treatment is essentially intended to remove the water provided by the sizing composition and, where appropriate, makes it possible to accelerate the crosslinking of the sticky fihnogenic agents.
• Treatment conditions may vary depending on the mass of the treatment. In general, the drying is carried out at a temperature of the order of 110 to 140 ° C for several hours, preferably 12 to 18 hours.
• the yarns coated with the sizing composition according to the invention can be made of glass of any kind as long as it is suitable for being fiber, for example glass E, C, AR (alkali-resistant), or low boron level (less than 5%).
• These same threads consist of filaments whose diameter can vary to a large extent, for example 9 to 17 ⁇ m, preferably 11 to 13 ⁇ .
• these threads have a count between 30 and 160 tex, preferably 40 and 60 tex.
• Such cut glass strands are distributed regularly and homogeneously within the resin, even when the thickness projected onto the mold is large, which makes it possible to have excellent quality reinforcement.
• Another subject of the invention relates to the sizing composition capable of coating said glass strands, which composition is characterized in that it comprises an aqueous mixture of at least one polyvinyl acetate, of at least one copolymer d vinyl acetate and at least one other unsaturated monomer and at least one epoxy as defined above
• the sizing composition is an aqueous mixture comprising the constituents below, in the following weight contents expressed as percentages solid materials: - 20 to 50% of at least one polyvinyl acetate, preferably 30 to 40% - 20 to 45% of at least one copolymer of vinyl acetate and at least one other unsaturated monomer, advantageously an olefinic monomer such as ethylene, preferably 30 to 40% - 10 to 20% of at least one epoxy, preferably 12 to 16% - 1 to 20% of at least one lubricating agent, - 0 to 5% of at least one coupling agent, preferably greater than 2% - 0 at 5% of at least one anti-static agent
• the sizing composition comprises between 5 and 15% by weight of solid matter, preferably between 7 and 12%.
• the liquid phase consists of 100% water.
• Another subject of the invention relates to composites comprising glass strands coated with the sizing composition.
• Such composites comprise at least one thermosetting material, preferably a polyester, a vinylester, an acrylic, a polyurethane, a phenolic or epoxy resin, and glass strands made up, in whole or in part, of glass strands in accordance with invention.
• the content of glass in the composite is generally between 20 and 45% by weight, and preferably between 25 and 35%.
• the glass strands give the composites which contain them better resistance to aging, especially in a humid environment.
• Another subject of the invention is the use of glass strands coated with the sizing composition for the production of parts by the open mold molding technique, in particular by simultaneous spraying of said strands and of resin.
• the invention also relates to the use of said glass son for the manufacture of molded parts operating in a closed mold, in particular by the LFI technique.
• the properties relating to glass strands coated with the sizing composition and to the composites incorporating said strands are measured as follows: - the loss on ignition, in percentage, of the sized glass strand is measured under the conditions of the ISO 1887 standard, - the flock is measured by simultaneously passing the strands unwound from 2 rovings on a tie, at a speed of 200 m / ma.
• the flock is defined by the quantity of fibrils, in mg, obtained after passing through a mass of thread of 3 kg. It is expressed in mg / kg of yarn.
• a sizing composition is prepared in the form of an aqueous solution comprising, as a percentage by weight of the solid materials: "sticky film-forming agents - polyvinyl acetate (1 ; molecular weight: 50,000 35.7 vinyl acetate copolymer- ethylene ⁇ 35.7 epoxy resin (3) 12.6 amino-epoxy resin (4) 3.7
• anti-static agent LiCl 4.5
• water sufficient quantity to give 100 ml of sizing composition
• the preparation of the sizing composition is carried out as follows: The methoxy groups of the silane (5) are hydrolyzed by adding acid to an aqueous solution of this silane which is kept stirring. The other constituents are then introduced, still with stirring, and the pH is adjusted to a value of 4 ⁇ 0.2, if necessary. The weight content of solid matter in the sizing composition is equal to 10.9%.
• the sizing composition is used to coat, in a known manner, glass filaments E of approximately 12 ⁇ m in diameter drawn from glass filaments flowing from the orifices of a die, the filaments then being collected in the form of base wire windings with a title equal to 57 tex.
• the winding is then dried at 130 ° C for 12 hours.
• the basic threads extracted from 6 windings are brought together to form a roving.
• the wire thus obtained has a loss on ignition equal to 1.5%.
• the quantity of fill is equal to 24 mg.
• EXAMPLE 2 A sizing composition is prepared under the conditions of Example 1, consisting of an aqueous mixture comprising, as a percentage by weight of the solid materials: "sticky film-forming agents - polyvinyl acetate (1) ; molecular weight: 50,000 36, 1 - vinyl acetate-ethylene copolymer ⁇ 36.1 - epoxy resin ⁇ 12.8
• lubricating agent - mineral oil (6) 5.0 - silicone (7) 2.0 - ethylene glycol monolaurate (9) 3.0 - polyethylene imide polyamide salt (10) 0.3
• water sufficient quantity to give 100 ml of sizing composition.
• the weight content of solid matter in the sizing composition is equal to 7.5%.
• the yarn extracted from a roving obtained under the conditions of Example 1 has a loss on ignition equal to 1.55%.
• the amount of fill is equal to 3.6 mg.
• EXAMPLE 3 A sizing composition is prepared under the conditions of Example 1, consisting of an aqueous mixture comprising, as a percentage by weight of the solid materials: "sticky film-forming agents - polyvinyl acetate (1) ; molecular weight: 50,000 34, 8 - vinyl acetate-ethylene copolymer (2) 34.8 - epoxy resin (3) 12.3 - amino-epoxy resin (4) 3.6 "coupling agent - gamma-methacryloxypropyltriethoxysilane (5) 2.2
• water an amount sufficient to give 100 ml of sizing composition.
• the weight content of solid matter in the sizing composition is equal to 11.5%.
• the yarn extracted from a roving obtained under the conditions of the example 1 has a loss on ignition equal to 1.70%.
• the quantity of fill is equal to 1.5 mg.
• EXAMPLE S (Comparative) A sizing composition is produced under the conditions of Example 4 modified in that it additionally contains 0.45% by weight of LiCl. The weight content of solid matter in the sizing composition is equal to 9.8%. The yarn extracted from a rovel has a loss on ignition equal to 1.52% The quantity of flock is equal to 7.6 mg. EXAMPLES 6 to 11 The wire obtained according to examples 1 to 5 is used to manufacture composite parts by the technique of molding by simultaneous projection under the following conditions:
• the mold in which the cut wires and the resin are projected is a stair-shaped mold with a vertical wall 1 m high, then a step 0.20 m deep and 0.2 m high and finally a horizontal wall 1 m long.
• horizontal wall has two grooves 2 cm deep to assess the conformability of the cut son / resin mixture.
• the mixture projected onto the mold contains approximately 30% by weight of glass and has an average thickness of the order of 5 mm.
• the performance of the cut son / resin mixture is evaluated for the following parameters: - boiling / working time respectively corresponding to the ability of the air bubbles to be expelled from the mixture projected onto the mold by passing a boiling roller, and the ability of the wires to be impregnated with the resin, - held in a vertical wall, - conformability, evaluated at the level of the grooves in the horizontal wall, - speed of impregnation of the wires cut by the resin.
• Examples 6 to 8 according to the invention make it possible to achieve an excellent compromise in terms of application properties: a particularly high vertical wall resistance associated with an impregnation speed which can be modulated according to the size, from moderate (examples 6 and 7) to slow (example 8).
• the glass strands of Example 3 make it possible in particular to achieve the same level of performance as the glass strands adapted to this technique (Reference 1).
• the glass strands coated with a size not comprising the mixture of sticky film-forming agents (examples 9 and 10) have insufficient conformability.
• the yarns according to the invention have a lower wadding production than the yarns provided for the intended application (Reference 1). In Example 8, the fluff production is considerably reduced.
• EXAMPLES 12 AND 13 The performance of the wire according to Example 3 is evaluated for the LFI application compared to the OC 900 wire (Reference 2) suitable for this technique.
• the parameters are: - the number of loops present on 500 meters of wire unwound from a winding, generally a roving, - the integrity of the wire subject to the following conditions: the wire unwound from a roving is introduced in a WOLFANGEL 500 cutter which cuts and projects it substantially horizontally on a vertical wall (cutting speed: 1200 mmin; length: 12 mm).
• the integrity of the cut wire is visually measured on a scale of values ranging from 1 (poor, cottony appearance) to 5 (very good, no breakage of the wire) the impregnation speed of the wire cut by the resin, measured visually on a scale ranging from 1 (very slow speed) to 5 (very fast).
• Example 12 Example 13 Thread Example 3 Reference 2 Number of loops 30 43 Integrity 3.5 3.5 Impregnation speed 1 1
• the thread according to the invention has a reduced number of loops compared to the spooling for integrity and speed d 'identical impregnation.

Landscapes

• Chemical & Material Sciences (AREA)
• Materials Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Manufacturing & Machinery (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
• Surface Treatment Of Glass Fibres Or Filaments (AREA)
• Reinforced Plastic Materials (AREA)
• Laminated Bodies (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34630244

Family Applications (1)

Country Status (3)

Families Citing this family (3)

Family Cites Families (7)

• 2003
  • 2003-12-17 FR FR0314800A patent/FR2864072B1/fr not_active Expired - Fee Related
• 2004
  • 2004-12-01 EP EP04805872A patent/EP1725506A2/de not_active Withdrawn
  • 2004-12-01 WO PCT/FR2004/050634 patent/WO2005058770A2/fr not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events