MXPA96004086A - Apron of glass fibers and glass fibers with apprint and poliolefi reinforcement items - Google Patents

Abstract

The present invention relates to an aqueous sizing composition for glass fibers, comprising: a) an inorganic, organofunctional coupling agent, b) a modified polyolefin acid film-forming material, c) a stabilizer selected from the group consisting of in: i) hypophosphites selected from the group consisting of alkali metal hypophosphites, alkaline earth metal hypophosphites, ammonium hypophosphites and mixtures thereof, and ii) mixtures of one or more of the stabilizers of i) with an antioxidant selected from the group consisting of in hindered phenols, diarylamines, thioethers and mixtures deést

Description

APRON OF GLASS FIBERS AND GLASS FIBERS WITH APPRINT AND REINFORCING ARTICLES OF POLIOLEPHINS BACKGROUND OF THE INVENTION The present invention relates to chemically treated glass fibers, strands or yarn, wherein the fibers impart an improved strength to the reinforcement of thermoplastics and in particular polyolefins. Glass fibers are produced from molten glass that flows by the action of gravity through ,, - • multitude of small holes in a precious metal device, called a hub. In The Manufacturing Technology of Continuous Glass Fibers, Library of Congress Catalog Card, Number 72-97429, by K.L. Loewenstein, Elsevier Scientific Publishing, 1973, page 29, describes typical formulations of glass fibers. Glass fibers are, for example, those known as "glass E", "glass S", "glass D" and are typically between 3 and 30 microns in diameter. Once the fibers have cooled very briefly after their exit from the bushing and usually very close to the bushing, these fibers are treated with a chemical treatment formulation commonly known in the art as sizing composition or sizing. The sizing serves to make the fibers more compatible with the material that is going to be used in the end to reinforce and make easier the working of the fibers. The aqueous sizing can be applied "" "by sprayers, rollers, tapes, measuring devices or any other device of similar application.The squeezed glass fibers are gathered into bundles or strands comprising a plurality of individual fibers, generally from 200 to more of 3000. Finished glass fibers can generally have between about 0.01 and 5 percent sizing composition on the weight of the glass fiber.After its formation and treatment, the strands can be wound on a reel or "forming coil" and / or can be sectioned The forming coils or the sectioned strands are usually dried in an oven or at room temperature to remove some of the moisture from the fibers.The strands of treated fibers can be used to reinforce various materials such as thermoplastic polymers Thermoplastics can be of different types, including chemically coupled thermoplastics and non-chemically coupled. Particular types of sizing fiber strands have generally been employed for chemically coupled or non-chemically coupled thermoplastics, such as polyalkylenes, including polypropylenes. U.S. Patent 5,130,197 to Temple discloses a size having 1) an amino-silane coupling agent, 2) a polyolefin resin modified with carboxylic compound, ~ * "3) an epoxy, urethane or polyester resin or copolymer of the and 4) a binder stabilizer These sizing fibers are preferably used to reinforce non-chemically coupled polypropylene homopolymer US Patent 4,341,677 to Tamosauskas also describes a sizing having a polymer that forms a film, coupling agent and an oil-in-water emulsion of an antioxidant such as hindered phenols and diarylamines. "The fiber-reinforced plastics industry continues its research studies to improve the mechanical properties both initially and after heat aging." An object of the present invention is to provide chemically treated or pre-treated fibers as well as strands or bundles thereof which have better initial mechanical strength and / or better retention of mechanical strength and / or color upon thermal aging, when used to reinforce chemically coupled thermoplastic polymers and / or non-chemically coupled ones such as polyalkylenes.

SUMMARY OF THE INVENTION The objects of this invention are achieved by glass fibers treated with a size having an inorganic coupling agent with organic function, a polymer which forms a polyolefin-compatible film, one or more stabilizers which are effective against oxidation phenomena, and a vehicle for the application of sizing to glass fibers. The stabilizers are, such as 1) phosphinates, phosphites, hypophosphites, sulphites and bisulfites of alkali metal, alkaline earth metal, and ammonium, phosphinates and / or organic phosphites and mixtures of them; and 2) mixtures or combinations of the stabilizers of 1) with other types of stabilizers, such as hindered phenols, diarylamines, thioethers and the like Optionally, the sizing may have a branched carboxylic acid copolymer partial ester as well as one or more other components such as film forming polymers, coupling agents, lubricants for fibers and the like Another aspect of the invention is the polyolefin reinforcement consisting of a plurality of prepared glass fibers bearing the aforementioned size.

DETAILED DESCRIPTION OF THE INVENTION A fiberglass suitable for reinforcement can be suitably treated in accordance with the present invention. Glass fibers such as soda lime glasses and borosilicate glasses such as "E" glass and "621" type glass are especially suitable for this practice. You can also use "E" glasses and "621" glasses formulated "^ with lower boron or boron and fluorine free quantities." Examples of some suitable glass fibers are those described on page 29 of The Manufacturing Technology of Continuous Glass Fibers by KL Lowenstein, published in 1973 by Elsevier Scientific Publishing Company, Library of Congress Card, number 72-97429 The glass fibers to be treated according to this invention can typically be produced in accordance with the U.S. Patent No. 2,133,238 Glass fibers are formed by high speed drawing from molten glass cones placed at the tip of small holes in one or more bushings of a glass melting device or furnace. After its formation, the filaments are treated with a chemical sizing prepared in the manner described below.The application of the sizing to the filaments may have r "" "'place while moving these at a speed of the order of 1000 to 20,000 feet per minute (300 to 6100 meters / minute) in the immediate vicinity of the hot bushings and the glass furnace in which the glass melts . The application of sizing to glass fibers is well known in the art and can be carried out by conventional methods such as a tape applicator, a "contact roller" applicator or by spraying. US Pat. No. 2,728,972 discloses details of a sizing applicator The amount of sizing deposited on the glass is from about 0.01 to about 5 weight percent and preferably about 0.3 to about 2.5 to 3 weight percent of the treated fiberglass strand After sizing, the glass fibers are bundled or bundled with a plurality of fibers typically by use of a collection shoe and / or a device that '* "pushes the strands as illustrated in U.S. Patent Nos. 3,292,013 and 4,248,935. Additionally, or alternatively, the fibers, before or after being gathered into one or more strands, can be made smaller by a blade that cuts the fibers and / or the strands together to lengths of about one sixth (1.6 mm) to approximately three inches (76.2 mm). The sectioned strands can be deposited in bags or boxes for easier handling. The amount of moisture in the wet-section fiberglass is generally in the range of up to about 20 weight percent. The glass can be gathered into strands and collected as a continuous strand of glass fibers in a forming coil and subsequently cut in a separate wet cutting process or, after drying, in a dry cutting process in similar lengths to those of the direct wet cutting process. The forming coil can be dried to remove residual moisture at room temperature or by heating in an oven. The size of the present invention has, in addition to water, from about 1 to about 50 weight percent solids based on both weight percent non-volatiles or the dry film. Another way of establishing it is that the amount of water is from about 50 to about 99 weight percent of the size. On the basis of the percent by weight of the non-volatiles, the amounts of the non-aqueous components in the sizing are as follows: about 1 to about 30 weight percent of one or more coupling agents with organic function, from about 50 to about 90 weight percent of the polymer that forms film and is compatible with polyolefin, and from about 1 to 25 weight percent of one or more stabilizers for the oxidation phenomena. Optionally, but preferably, a branched carboxylic acid copolymer partial ester is present in an amount of about 1 to about 10 weight percent of the non-volatile components. Other components, optionally added, are present in smaller amounts than the polyolefin-compatible film-forming polymer.

The inorganic coupling agent with organic function "* useful in the present invention can be an organophosphorus silane compound used as the coupling agent between the predominantly organic sizing and the inorganic glass and any of the known silane coupling agents can be used. The specialty Examples of organofunctional silane coupling agents useful in this invention are silanes with amino function and epoxy function silanes Commercially available silanes such as ~ "gamma-aminopropyltriethoxy silane and gamma-glycidoxypropyltrimethoxy are useful. silane. These silanes are from OSi specialties Company of Tarryto n New York as A-1100 and A-187, respectively, and from Dow Corning Corporation as Z-6011 and Z-6040, respectively. The silane with amino function is preferred and this silane can be hydrolyzed to a certain degree before it is used in the reaction with an effective amount of a suitable acid such as carboxylic acid such as acetic acid. Other coupling agents which can be used are transition metal coupling agents such as for example titanium and zirconium coupling agents which carry an organic function such as monoalkoxy, monoalkoxy-pyrophosphate, chelate, and coordination types and agents of copulation of Werner and the like. They all provide the coupling of the interfacial interface area between the inorganic surface of the glass and the organic matrix polymer. * * The polyolefin-compatible film-forming polymer is preferably an aqueous emulsion of a chemically modified polyolefin. The term "chemically modified polyolefins" refers to modified polyolefins with either amorphous or crystalline acid of the type produced by the method disclosed in U.S. Patent 3,416,990 (Robinson); 3,437,550 (Paul) and 3,483,276 (Mahlman). A discussion of these polyolefins, their modification and emulsification can be found in U.S. Patent 5,130,197 One of the examples of crystalline carboxylated polypropylene polymer that can be used in the emulsion to produce glass fibers of the present invention is the Hercoprime® type G resin from Hercules, Inc., Bloomington, Delaware One of the examples of carboxylated amorphous polypropylene polymer that can be used in the sizing composition to prepare the glass fibers of the * "'" - present invention is that which exists in commerce as Epolene E-43 from Tennessee Eastman Co. Another suitable example is an emulsion of Epolene E-43 from Byk-Wax under the trade name Aquacer 841 emulsion. This latter emulsion is the preferred polyolefin-compatible film-forming polymer that is present in sufficient amounts to provide a predominant amount of the solids or non-volatiles of the aqueous sizing. An aqueous polyolefin emulsion can be prepared from the carboxylated amorphous polyolefin such as the carboxylated amorphous polypropylene polymer or the crystalline carboxylated polyolefin such as crystalline carboxylated polypropylene, Hercoprime® G resin, or mixtures. Any of the surfactant compounds or combinations of surfactant compounds known to those skilled in the art may be employed in the emulsion polyolefins. ^ ~ A commercial version of the aqueous polyolefin emulsion is the carboxylated amorphous polypropylene which is from National Starch, Procter Division, under the trade name Protolube RL-5440 polypropylene emulsion. This product has a pH of about 9.5 ± 0.5, a solids content of 32 ± 1, a color that varies from a tan to gray emulsion and is slightly cationic and has a boiling point of about 100 ° C, a specific weight of 0.98. A infra-red spectrophotometric curve and a differential scanning colorimeter curve of the emulsion product RL-5440 are shown in Figures 3 and 4 of US Patent 5,130,197., describing in it the procedure to obtain the curves. Another component of the chemical treatment composition, which is preferably present, is one or more stabilizers against the oxidation phenomenon. It has been discovered that particular "" types of stabilizers that can act as antioxidants provide particular benefits to the thermoplastic polymer such as polyolefins, polyamides, and polyesters (PBT and PET) that are reinforced with glass fibers or loaded with siliceous material such as glass lamellae. and similar. These emulsifiable, dispersible or water soluble stabilizers include inorganic and organic phosphinates, phosphites and sulfites. These may be used alone or in mixtures thereof or in mixtures with any other emulsifiable, dispersible or soluble antioxidant known to those skilled in the art for use in coatings and films on discrete surfaces such as fibers. For example, the antioxidants of U.S. Patents 4,483,948 may be used; and 4,341,677, these patents being incorporated herein by reference. Some examples of these other types of antioxidants include hindered phenols, diarylamines, thioethers, and the like. Examples of the phosphinates, phosphites and sulphites that can be used include the phosphinates, phosphites, hypophosphites, hydrogen phosphites, sulfites, bisulfites and alkali metal hydrosulphites and alkaline earth metal and water soluble ammonium. Dispersible or emulsifiable organic phosphites and / or phosphites in water can also be used.

Another suitable type of stabilizer is that of the alkali metal r "phenylphosphonates, an example of which is sodium benzene phosphonate.This material is present in an amount similar to the aforementioned amounts and larger amounts may be used if required. Additional benefits An example of sodium benzene phosphonate is that of Stauffer Chemical Company having the formula C6H602PNa with a formula weight of 164. Other examples of anti-oxidant type stabilizers include organic phosphites such as diisodecyl pentaerythritol phosphite, phosphites of trialkyl, such as triisodecyl phosphite, tristearyl phosphite, trimethyl phosphite, tris- (2,4-di-tert-butyl-phenol) phosphite, tris- (2,4-dimethylphenol) phosphite, alkylphenyl phosphites as isooctyl diphenyl phosphite, diisooctyl phenyl phosphite, hindered organic phosphites such as neopentanotetrayl dioctadecyl phosphorous acid cyclic ester, phosphorous acid and cyclic phosphorous of neopentanotetrayl bis (alkylbutylphenyl), and others such as those described in U.S. Patent 5,278,210 incorporated herein by reference. A suitable example is Irgafos 168 which is tetrakis (2,4-di-tert-butylphenyl) 4, '-biphenylylenediphosphonite. Preferred stabilizers are the water-soluble inorganic hypophosphites and the one that is preferred first is sodium hypophosphite as the only stabilizer present in a preferred amount of about 3 to about 10 weight percent of the aqueous treatment composition. A suitable sodium hypophosphite is that of Fisher Scientific Company as a solid sodium hypophosphite having the formula NaH2P02.H20 This material is soluble in water and when the vehicle for the chemical treatment composition is water, it is simply dissolved in the water. chemical treatment composition or it is previously dissolved and added to the chemical treatment composition In terms of the amount of phosphite or phosphonate stabilizer, larger quantities can be used to provide even greater benefits in the mechanical properties. stabilizer shall not be exceeded when the quantities of the other components they are limited insofar as they detrimentally affect the overall behavior of the sizing. The stabilizing effective amount of the stabilizer is that which improves the mechanical properties of the reinforced glass fiber and / or thermoplastic polymer matrix loaded with siliceous material. In addition, mixtures of these stabilizers are useful in the chemical treatment composition and preferably a mixture is used. The stabilizer mixture can be incorporated into the chemical treatment composition or added to a secondary treatment after the chemical treatment of the reinforcing fibers has been applied "* first among the examples of other antioxidants that can be used in combinations of stabilizers with one or more of the phosphites, phosphonates and sulphites are the thioethers and polymers thereof A non-exclusive example of these is di (tridecyl) thio-dipropionate with a chemical formula S (CH2CH2COOC13H27) 2. A suitable thiodipropionate is that of Grace from its Evans Chemetics Unit in Waterloo, New York, with the name of the "Evanstab" product 13. Another example is distearyl dithiodipropionate (DSTDP) from Eastman Chemical Company, Tennessee under the tradename PA 49M. The amount of the mixture is generally in the range of amounts set forth above for the stabilizer. Optionally, but preferably, the sizing also has a partial ester of carboxylic copolymer which can be used in this invention as an emulsifier and / or lubricant. - This and its derivatives are polymers with hydrocarbon side chains and ethoxylated ester. A commercial version of a suitable carboxylic copolymer partial ester is that of Akzo Chemie America, of Chicago, under the tradename partial ester Dapral® GE 202. This material has an average molecular weight of about 20,000, a specific gravity of 1.05 to ° C, a flash point of 178 ° C COC (Cleveland Open Cup) and is a viscous, yellowish liquid with little odor. This material is a partial ester of a branched carboxylic acid copolymer. This polymer has a comb structure and the main chain consists of carbon atoms only. The alkyl branches are hydrophobic and the ester and ether groups are hydrophilic. The sizing may optionally have other ingredients that are known to those skilled in the art as useful in glass sizing in fibers such as emulsifiers, antifoams, surfactants, etc. The sizing can be prepared by any of the methods known to those skilled in the art, and applied to the fibers and / or fillers by any of the methods known in the art. For example, when the glass fibers are produced by a dry sectioning method, it is preferable to have an additional film-forming polymer in the sizing to improve the integrity of the strand. The vehicle for the chemical treatment composition is any of the materials known to those skilled in the art for the application of chemical treatment to fibers during their formation or after their formation or to other types of reinforcement during their formation. The vehicle can be an organic solvent or water or a combination to produce foams and gels for chemical treatment. Water is the preferred vehicle to give an aqueous chemical treatment composition. The vehicle, such as water, is present in effective amounts to give a total of solids (non-volatile content) in the sufficient range to achieve a viscosity of the chemical treatments for application to the fibers for reinforcement or to the loads. Generally, the water is present in an amount sufficient to give a total solids in the range of about 1 to about 50 weight percent and preferably about 5 to 20 weight percent. In any case, the amount of the various components and the amount of water will have to be balanced so that the viscosity of the solution is not greater than about 150 centipoise at 20 ° C. Solutions having viscosities greater than 150 centipoise are difficult to apply as an emulsion, dispersion or aqueous solution to fibers during their formation, especially to glass fibers that are formed from glass melt streams with conventional type application equipment without cause breakage of fiber continuity. It is preferred that the viscosity of the aqueous chemical treatment composition for application to glass fibers during their formation be in the range of about 20 to 60 centipoise at 20 ° C for the best results. If the aqueous chemical treatment composition is prepared with thixotropic agents to make it in the form of foam or gel, then the viscosity will be appropriate for such formulations and the application equipment will be appropriate for the application of foams and gels to the fibers or to the reinforcement. The aqueous chemical treatment composition can be prepared by adding each of the components simultaneously or sequentially one after the other, but the components can also be pre-diluted before being combined and diluted with water in the aqueous sizing. This is to enhance its solubility, dispersibility or emulsifiability. The treatment with the aforementioned aqueous chemical treatment composition is not only beneficial for strengthening the fibers, but also the inorganic fillers that are sometimes used in reinforced composite bodies would benefit from this treatment. Non-exclusive examples of these inorganic fillers include mica, wollastonite, talc, clay, lamellar glass and novaculite. The contact of the fillers with the aqueous sizing is done by spraying or dipping or the like as a convenient way of treating them. The dry fibers are used to reinforce polymer matrices in any of the molding processes known to those skilled in the art using sectioned strand, continuous strand or mixtures thereof.

Preferably, the strands of sectioned fibers are mixed with the polymer resin of the matrix in a dry powder mixture to produce a homogeneous batch of matrix polymer. The batch can be molded by compression or injection to produce the shaped device or fiber reinforced polymer part. These sized glass fibers are used in the molding of fiber-reinforced polymers, such as fiber-reinforced polypropylenes, blends of polypropylenes and polyethylenes and polyalkylene terephthalates, including poly (ethylene terephthalate) and poly (butylene terephthalate). ), polyamides, polyphenylene oxide, polystyrenes and other similar polar thermoplastic polymers, copolymers, mixtures and alloys. PREFERRED EMBODIMENT The preferred embodiment uses glass fibers which are treated, after drying, by a wet sectioning method having a dry residue of the size in which the fibers have a length of about 1/8 to 1/2 inch (3 cm to 1.25 cm). The fibers have conventional filament diameters which may vary from about 1 micron to more than 30 microns but preferably are in the diameter from about 10 microns to about 16 microns. The aqueous sizing preferably has the formulation with ranges of the preferred amounts for the components as shown in Table A: TABLE A COMPONENT PERCENTAGE IN SOLID WEIGHT Gamma-aminopropyltriethoxysilane 7.5-a-23.5 Polypropylene emulsion 64-to-84 Sodium hypophosphite 3.0-a-15 Partial ester of carboxylic copolymer 0.3-to-2.3 The fibers of this invention can be used to reinforce thermoplastics that are chemically coupled The term "chemically coupled" means a thermoplastic such as polypropylene to which an acid-modified polyolefin has been added that provides chemical fractions to react with the components This acid-modified polyolefin chemical coupling agent is added to the thermoplastic as a physical mixture prior to compounding with the fibers and may be, for example, polypropylene with side carboxylic acid groups.These side carboxylic acid groups are assumed to be they react with the basic amino groups of the amino silane to create a strong bond between the glass to which the silane binds and the chemical coupling agent compatible with polyolefin.An example of chemically coupled polyolefin which is suitable for use with the fibers of this invention is in the trade as PCO-72 of Him ont PCO-72 is a mixture of unmodified polypropylene homopolymer and a small amount of modified polypropylene homopolymer. The fibers of this invention can also be used to reinforce thermoplastics that are not chemically coupled. In this type of thermoplastics, the chemical coupling agent mentioned above is not added to the thermoplastic. An example of a non-chemically suitable coupled thermoplastic is that which is commercially available as Profim® 6523 polypropylene from Himont and is a polypropylene homopolymer. The prepared fibers of this invention generally provide good results both in the case of chemically coupled thermoplastics and non-chemically coupled ones. The following is an example of a sizing preparation method of this invention. Approximately 24 kilograms (kg) of polypropylene emulsion was added to approximately 20 liters of deionized water at room temperature in a large tank with gentle agitation. It is important to avoid the entry of air and the generation of foam in the mixture. In a separate tank, approximately 3.1 kg of gamma-aminopropyl-triethoxy silane was added to approximately 37 liters of deionized water having 1 kg of acetic acid, at room temperature. After gentle stirring for approximately 10 minutes, this was added to the above mixture with moderate agitation. The above-mentioned amount of sodium hypophosphite is dissolved in water and added to the mixture. In a separate tank 150 grams of Dapral® partial ester were added to approximately liters of deionized water at 25 ° C. After stirring for about 10 minutes, this was added to the above mixture. The glass fibers were prepared with a roller applicator and sectioned in the wet state. The fibers were dried and combined with a chemically coupled commercial homopolymer polypropylene (CCHP) using a counter-rotating extruder at a glass content of 30 weight percent. The combined glass and polypropylene mixture was molded into a 200 ton injection molding unit by a method known in the art and then tested for strength. The fibers were also combined and molded with a commercially non-chemically-coupled homopolymeric (HP) polypropylene in an analogous manner. The sizing formulations of Table 1 were prepared in a manner similar to that of the preferred embodiment which is further described in Example 2 of Table 1.

Each of the sizes of Table 1 was applied to a plurality of glass fibers to prepare a strand construction having 800 strands per strand with the strands having a fiber diameter of 13 microns. The strands for each example were wound on separate formation coils. A number of forming coils were unrolled for each example, between 2 and 12, but preferably 4, and were combined into a strand that was passed through an applicator to apply additional moisture and / or sizing before being sectioned in the wet state. Normally, it is preferred to section a multitude of strands, usually in the range of about 10 to 15 per cutting blade. The sectioned strand can be dried directly after sectioning or collected and dried in a continuous fluidized bed dryer. The second batch of sizing formulations of Table 1 was prepared and together with those also those of Illustrative Example 1 (Illustrative Example IB) and those of Example 2 (Example 2) were prepared. These additional formulations are collected as Illustrative Example IB, Example 2B, and Examples 3-6 in Table 1 and all employ sodium hypophosphite as a stabilizer or antioxidant. The sizes were applied to the glass fibers in the form of strand constructions and sectioned, combined, molded and tested in polypropylene homopolymer and chemically coupled polypropylene in a manner similar to that of Examples 1 and 2 and 7-9 in terms of properties initial mechanics.

TABLE 1 Sizing Forrnulations (% of total solids) The sectioned strands for each example are '"" "- combined, molded and tested separately in a manner similar to polypropylene homopolymer (12 Mf Himont F30S) and chemically coupled polypropylene (addition of 2.5 percent of Exxelor P0X1 1015 to the base polypropylene resin). The combination was carried out by making the plastic samples of fiber reinforced polypropylene (FRP) by extruding the fiberglass strands sectioned with agglomerates of the polypropylene matrix polymer in a double screw extruder Werner Pfleiderer ZSK 30 (mm). The sectioned strands were directed downstream using a vibrating feeder of glass strands.

The agglomerates of the matrix polymer and the possible additional additives of the polymer were mixed dry before insert them into the extruder. The screw speed of the extruder was 300 rpm and the vacuum was complete. The injection molding was carried out with a Battenfeld CD750 machine and the screw speed was 100 rpm and the clamp pressure was 100 bar and the back pressure was 35 bar.

The samples were molded using a mold of the ISO type. The compounds for each example were tested for initial mechanical properties and color. They were also tested for retention of mechanical properties and color after heat aging at 150 ° C for a total of 13 days. The results of the initial mechanical properties "~ are listed in Table 2 and the results of the mechanical properties after heat aging at various times of the 13-day period are collected in the Tables 3 and 4. The tests were carried out according to the following methods for the established test: Traction: on a Zwick 1476 machine according to ISO 527 with a load of 100 kilonewtons at 2 millimeters (mm) / minute for the measurement of tf. module and 5 mm / minute for resistance measurements for head speed, in which the sample was supported by wedge mechanical flanges; Flexion: in a Zwick A model according to ISO 178 at 2 mm / minute for the module and 5 mm / minute for the resistance with a load of 3 kilonewton with a configuration of bending of three points and with a span of 64 mm; Impact: with a Zwick impact tester (pendulum type) according to ISO 179 (Charpy) and ISO 180 (Izod) pattern; color: Dr Lange's Colorimeter; and content in glass: by combustion of the test samples broken.

The units of the following tables are SI units - "~: using the following abbreviations: MPa = (megapascals); GPa = (gigapascals); J / m = (joules / meter); and kJ / meter2 = kilojoules / square meter; (mm) = millimeters; (μm) = mieras; 5 (g / cm3) = grams per cubic centimeter; Whiteness index is the opposite of the yellowing index. The yellowness and whiteness indices are related so that a low value for yellowing or a high value for whiteness are indicative of a better behavior. In the first part of Table 2, Illustrative Example 1 was made with examples 1-2 and 7-9. In the second part of Table 2, Table 2 (B), Illustrative Example IB was carried out with examples 2b and 3-6. The formulation of Example 2 as shown in Table 2 resulted in properties Increased mechanical properties in the homopolymer in relation to the illustrative example. Although the glass content was slightly higher, the tensile strength was 23 percent higher, the flexural strength was 20 percent higher, the Charpy value without notch was 30 percent higher high and the non-entangled Izod was 59 percent higher. The color indices indicated a whiter product (higher L index) and less yellow (lower b index). All of Examples 1-9 gave comparable or superior initial mechanical properties. The results of the mechanical properties of Table 2 for Examples 2B and 3-6 and Illustrative Example IB '' 'show a connection between the amount of sodium hypophosphite in the sizing formulation and the level of mechanical properties, Example 4 had the lowest amount of sodium hypophosphite and also had the lowest level of mechanical properties. Example 5 had the highest amount of sodium hypophosphite and had the highest level of mechanical properties. The mechanical properties for most of the sizing formulations of Examples 2-9 of f Table 1 as shown in Table 2 were mechanical properties equivalent to those obtained for the formulation of the Illustrative example 1. As indicated in Table 3, the samples were taken after heat aging at 150 ° C on the first, fifth, sixth, ninth and thirteenth days and were tested for tensile and impact properties. Examples 2 and 8 gave significantly better heat aging results than the illustrative example without the antioxidant. The product of Example 9 gave good results until day 13 and 0 then failed to the extent that it could not be measured due to oxidation. The heat aging properties of the product of Example 9 are for the most part similar to those of Example 8 up to day 13. Given the similarities in the formulation and the data over 9 days, the value of day 13 can be deduced . The impact properties (Charpy without '"' notch and Izod without notch) in the homopolymer polypropylene are listed in Table 3. All the examples with antioxidant or stabilizer have properties superior to those of Illustrative example 1. In Izod without notch, both the product of Example 8 and that of Example 2 stand out as significantly better. The retention of unhardened Charpy and non-entangled Izod properties were slightly different. The unflared Charpy impact test showed with Significance 1-2 and 7-9 retention of significantly better properties after 13 days than those of Illustrative Example 1. However, the results for Example 2 were slightly better than the of the others. The unnotched Izod differed further, and in Examples 8 and 2 it was significantly better than in Illustrative Example 1 and the other sizing formulations. The tensile strength and elongation properties for chemically coupled polypropylene after heat aging are reported in Table 4. In the chemically coupled polypropylene, three examples, 2, 8 and 9, were significantly better than the results of Illustrative Example 1. The retention of the impact of chemically coupled polypropylene with heat aging is also shown in Table 4. Similar results are observed, with Examples 2, 8 and 9 giving the best results in heat aging. From the data in Tables 1-4, it follows that the sizing and prepared glass fibers and reinforced polypropylene articles of the present invention provide a significant improvement in heat aging for reinforced polypropylene and significant improvements in the mechanical properties of the polypropylene homopolymer as well as a significant improvement in the color of both homopolymers and chemically coupled polypropylene in terms of higher L (whiter) and lower b (less yellow) indices.

TABLE 2. Mechanical properties and color Homopolymer polypropylene Himont F30s 12, Melt flow Himont F30s plus 2.5% Exxelor 1015 (chemically coupled) *** r TABLE 2 (B) Mechanical and color properties Homopolymer polypropylene Himont F30s 12, Melt flow Himont F30s plus 2.5% Exxelor 1015 (chemically coupled) r TABLE 3 Retention of tensile strength with heat aging of homopolymer PP after exposure to 150 ° C Table 3 (Continued) , intact Charpy and Izod intact without entalla with homopolymer heat aging PP after exposure to 150 ° C TABLE 4 Retention of tensile strength with heat aging of PP chemically coupled after exposure to 150 ° C Table 4 (Continued) Properties in heat aging Charpy without entalla and Izod without notch in chemically coupled PP, 150 ° C

Claims (24)

CLAIMS-

1. An aqueous sizing composition for glass fibers comprising: a) a coupling agent; b) a chemically modified polyolefin film-forming material; c) a stabilizer selected from the group consisting of: ## STR3 ## - i) phosphinates selected from the group consisting of alkali metal phosphinates, alkaline earth metal phosphinates, ammonium phosphinate, organic phosphinates and mixtures thereof; ii) phosphonites selected from the group consisting of 15 in alkali metal phosphonites, alkaline earth metal phosphonites, ammonium phosphonite, organic phosphonites and mixtures thereof; iii) phosphites selected from the group consisting of alkali metal phosphites, metal phosphites 20 alkaline earth, ammonium phosphite, organic phosphites and mixtures thereof; iv) hypophosphites selected from the group consisting of alkali metal hypophosphites, alkaline-earth metal hypophosphites, ammonium hypophosphite and mixtures thereof; v) sulfites selected from the group consisting of alkali metal sulphites, alkaline earth metal sulphites, ammonium sulfite and mixtures thereof; vi) bisulfites selected from the group consisting of alkali metal bisulfites, alkaline earth metal bisulfites, ammonium bisulfite and mixtures thereof; and? "vii) mixing one or more of the stabilizers from i) to vi) with an antioxidant selected from the group consisting of phenols, diarylamines, hindered thioethers and mixtures thereof.

2. The aqueous sizing composition according to claim 1 wherein the modified polyolefin film-forming material is a polyolefin modified by carboxylic acid.

3. The aqueous sizing composition according to claim 2 wherein the polyolefin modified by carboxylic acid is in the form of an aqueous emulsion.

4. The aqueous sizing composition according to claim 2 wherein the polyolefin is polypropylene.

5. The aqueous sizing composition according to claim 4 wherein the polypropylene modified by carboxylic acid is selected from the group consisting of modified polypropylene 5 by carboxylic acid, crystalline, and polypropylene modified by carboxylic acid, amorphous.

6. The aqueous sizing composition according to claim 3 wherein the emulsion is an oil-in-water emulsion and the > . < / sizing composition contains from about 50 weight percent to about 90 weight percent of the polyolefin modified by carboxylic acid, the percentages being based on the total solids of the sizing composition.

7. The aqueous sizing composition according to claim 1 wherein the stabilizer is a hypophosphite selected from the group consisting of alkali metal hypophosphites and ammonium hypophosphite.

8. The aqueous sizing composition according to claim 7 wherein the stabilizer is an alkali metal hypophosphite selected from the group consisting of sodium hypophosphite and potassium hypophosphite.

9. The aqueous sizing composition according to claim 8 wherein the stabilizer is sodium hypophosphite.

10. The aqueous sizing according to claim 1 wherein the stabilizer is a phosphinate which is sodium benzene phosphinate.

11. The aqueous sizing composition according to claim 1 wherein the coupling agent is an organophilic silane coupling agent which is an amine functional organosilane selected from the group consisting of gamma-aminopropyl-triethoxy silane, gamma-aminopropyltrimethoxy silane and hydrolysis products thereof.

12. The aqueous sizing composition according to claim 1 wherein the stabilizer is a mixture of stabilizers selected from the group consisting of a) a mixture of organic phosphites with hindered phenols and b) a mixture of organic phosphites, hindered phenols with thioethers, the aforementioned being present mixing in the size in an amount ranging from about 1 weight percent to about 25 weight percent, based on the percentages in the total solids of the sizing composition.

13. The aqueous sizing composition according to claim 1 further comprising a partial ester of an acid copolymer 5 branched carboxylic acid.

14. The aqueous sizing composition according to claim 11 further comprising a carboxylic acid in an amount sufficient to hydrolyze the silane coupling agent. - * »

15. The aqueous sizing composition according to claim 1 further comprising an organic solvent soluble or miscible with water.

16. An aqueous sizing composition for glass fibers, comprising: a) an organosilane coupling agent with amino function and products of hydrolysis thereof in an amount ranging from about 1 weight percent to about 30 weight percent; percent by weight; b) an aqueous emulsion of a polypropylene film-forming material modified by carboxylic acid in an amount ranging from about 50 weight percent to about 90 weight percent; and c) a stabilizer, in an amount ranging from about 1 weight percent to about 25 weight percent, selected from the group consisting of: i) phosphinates selected from the group consisting of alkali metal phosphinates, alkali metal phosphinates iron, ammonium phosphinate, organic phosphinates and mixtures thereof; ii) phosphonites selected from the group consisting of alkali metal phosphonites, alkaline earth metal phosphonites, ammonium phosphonite, organic phosphonites and mixtures thereof; iii) phosphites selected from the group consisting of alkali metal phosphites, alkaline earth metal phosphites, ammonium phosphite, organic phosphites and mixtures thereof; iv) hypophosphites selected from the group consisting of alkali metal hypophosphites, alkaline earth metal hypophosphites, ammonium hypophosphite and mixtures thereof; v) sulphites selected from the group consisting of alkali metal sulphites, alkaline earth metal sulphites, ammonium sulphite and mixtures thereof; vi) bisulfites selected from the group consisting of alkali metal bisulfites, alkaline earth metal bisulfites, ammonium bisulfite and mixtures thereof; 5 vii) mixing one or more of the stabilizers from i) to vi) with an antioxidant selected from the group consisting of phenols, diarylanes, hindered thioethers and mixtures thereof, the percentages being based on the weight of the total solids f of the aqueous sizing composition.

17. The aqueous sizing composition according to claim 16 wherein the stabilizer is sodium hypophosphite in an amount ranging between about 3 weight percent and 15 about 15 weight percent.

18. The aqueous sizing composition according to claim 16 wherein the amount of coupling agent varies between about 7.5 weight percent and about 23.5 20 percent by weight.

19. The aqueous sizing composition according to claim 16 wherein the amount of film-forming material varies between about 64 percent and about 84 percent by weight.

20. The aqueous sizing composition according to claim 16 further comprising a partial ester of a branched carboxylic acid copolymer in an amount ranging from about 0.3 weight percent to about 2.3 weight percent.

21. A plurality of glass fibers having a reduced moisture residue of the aqueous sizing composition according to claim 1 applied thereto in an amount ranging from about 0.3 weight percent to about 3 weight percent, based on the percentages in the weight of glass, in the loss to ignition.

22. A composite body of polyolefin reinforced with glass fiber where the glass fiber reinforcement is a plurality of glass fibers according to claim 21.

23. The polyolefin composite body reinforced with glass fiber according to claim 22 wherein the plurality of glass fibers are sectioned fibers and the polyolefin is polypropylene.

24. The composite body reinforced with glass fibers according to claim 23 wherein the polyolefin is a mixture of an unmodified polypropylene homopolymer and chemically coupled polypropylene.