CN101914270B - Special Anti-yellowing PBT (Polybutylene Terephthalate) plastic shell material of energy-saving lamp with lampshade and production method thereof - Google Patents

Abstract

The invention discloses a special anti-yellowing PBT (Polybutylene Terephthalate) plastic shell material of an energy-saving lamp with a lampshade and a production method thereof. The production method comprises the following steps of: baking polybutylene terephthalate for 2-5 hours at 120-150 DEG C; controlling water content to be less than 0.05 percent; subsequently, mixing the polybutylene terephthalate with a compound flame retardant, a complex antioxidant, an ultraviolet resisting agent, an opacifier and a flexibilizer through a mixer or separately entering a double-screw extruder from a metering feeder respectively; plasticizing and smelting; then adding glass fibers into the mixture; and extruding, bracing, cooling, dicing, uniformly mixing and packaging to obtain the product. In the invention, the product is far better than the universal PBT energy-saving material in the market, and has excellent anti-yellowing effect.

Description

Special material for anti-yellowing PBT plastic case of energy-saving lamp with cover and production method thereof

Technical field:

The invention relates to a special material for anti-yellowing PBT plastic case of an energy-saving lamp with a cover and a production method thereof, belonging to the technical field of modified polyester.

Background technique:

The heat distortion temperature of PBT resin can be greatly increased by adding glass fibers, and good flame retardant effect can be easily obtained by adding flame retardants, and it has excellent electrical properties, so reinforced flame retardant PBT composite materials are widely used Energy-saving lamps, electronic appliances, connectors and other fields in the lighting field. China is currently the world's largest production base for energy-saving lamps. The world's three major lighting companies: Philips, Osram (Siemens), and GE all produce OEMs in China. As far as the market is concerned, there are many classifications of energy-saving lamps. According to the material of plastic parts, there are PP, PBT, PC: PP materials are used for energy-saving lamp shells, and the safety performance and flame-retardant performance cannot be guaranteed, so they are mostly used for low-end products; reinforced flame-retardant PBT materials are used for energy-saving lamp shells, which are high-end flame-retardant. Material, because an important indicator to measure the plastic shell in the field of lighting energy-saving lamps from a safety point of view is: whether the plastic parts of the shell are made of flame-retardant and high-temperature-resistant (above 180°C) materials, and PBT can make its heat distortion temperature as high as 200 by adding glass fibers. The safety performance is fully satisfied if the temperature is above ℃. Therefore, the current PBT materials for energy-saving lamps account for more than 50% of the materials in the entire PBT modification industry in the Chinese market. The OEM factories of the three major lighting companies we have contacted generally divide electronic energy-saving lamp products into: conventional lamps, lamps with shades, and special lamps (for special purposes). The former generally belong to the low-end conventional varieties, and the competition between manufacturers is fierce, and the profit margin is very low; the lamp with cover is covered with a spherical or cylindrical sealed cover body outside the conventional lamp tube. There are multiple reflective surfaces. When the lamp is lit, it will reflect light downwards from different angles. Therefore, this structural design not only increases the brightness under the lamp, but also saves energy and increases the aesthetic feeling. It is a high-end product with high profit value. High, but the requirements for the modified PBT material of the lamp housing that carries the electronic components and lamp tubes on the entire energy-saving lamp will increase accordingly, because the bottom of the PBT plastic case is completely covered in the cover, and the light and heat emitted by the lamp tube cannot be dissipated. Going out, the double influence of continuous heat and light can easily cause yellowing of the entire lamp housing (plastic case), so it is required that the PBT material for the lamp housing (plastic case) has good yellowing resistance, that is, higher heat resistance and UV resistance. resistance and light fastness.

Patent CN200410017807.2 discloses a high-efficiency thermal oxygen stabilizer, which is characterized in that it can prevent the glass fiber reinforced PBT material from decabromodiphenyl ether and antimony trioxide flame-retardant from discoloration during processing. This patent is only limited to the problem of discoloration during processing, and does not consider the problem of discoloration in actual use, and decabromodiphenyl ether is easy to precipitate, which greatly affects the service life of the material.

Patent CN200510112125.4 discloses a high heat-resistant reinforced polybutylene terephthalate composition, which is characterized in that glass fiber reinforced PBT is enhanced by adding copolyester PETG, and its heat distortion temperature reaches about 255°C. The heat deflection temperature of this material is indeed high, but the material is not flame retardant, it is just a glass fiber reinforced material.

Patent CN200710172916.5 discloses a flame-retardant enhanced PBT polymer, which is characterized in that chain extenders such as diols or epoxy resins are combined with antioxidants such as organic hindered phenols, amines, and phosphites. Imparts high hydrolysis resistance to flame retardant reinforced PBT materials.

Patent CN200710172915.0 discloses a black light-resistant glass fiber reinforced PBT composite material and its preparation method, which is characterized in that inorganic carbon black is combined with a light absorber to endow the material with good mechanical properties after long-term light exposure.

As far as the current market requirements are concerned, customers have higher and higher requirements for the yellowing resistance of modified PBT materials used in energy-saving lamps, that is, after a certain period of use of energy-saving lamps, the modified PBT material parts need to maintain the original The chroma (white) of the modified PBT material should be prevented from changing too fast and too large from white to yellow.

Invention content:

The object of the present invention is to provide a special material for PBT plastic case of energy-saving lamp with cover and good yellowing resistance and its production method.

Technical solution of the present invention is:

A special material for anti-yellowing PBT plastic case of an energy-saving lamp with a cover, which is characterized in that it is mainly composed of the following components in weight percentage:

Polybutylene terephthalate 29.5～67.2%

Composite flame retardant 15～25%

Glass fiber 15～30%

Toughener 0～6%

Sunscreen agent 2～6%

Anti-ultraviolet agent 0.3～1.5%

Antioxidant 0.5～2%;

The composite flame retardant is A+B+C type. Flame retardant A is pentabromobenzyl polyacrylate (such as FR-1025 of Dead Sea Bromine Company in Israel); the biggest advantage of this flame retardant is that it has excellent anti-ultraviolet performance. It has the best anti-ultraviolet property in the agent, and its processing performance is excellent; but its shortcomings are also obvious. Epoxy resin, brominated polycarbonate (such as BC-52, BC-58 of Great Lakes Company of the United States), etc., have the advantages of white color, good anti-ultraviolet performance, and medium price; so the present invention uses A+B as the main flame retardant It not only utilizes the excellent anti-ultraviolet performance of flame retardant A, but also utilizes the advantages of flame retardant B in white color and high price, and combines the advantages of price and performance; C is an auxiliary flame retardant, mainly antimony trioxide or zinc borate or a combination of the two. The weight ratio of flame retardant A, flame retardant B and flame retardant C is: 5-10:5-10:1-5. The invention uses A+B+C as the flame retardant not only to meet the flame retardant requirements of PBT materials, but also to make this material have incomparably excellent anti-ultraviolet performance, which effectively compensates for the emission of energy-saving lamps in lamps with shades. The strong ultraviolet light and a lot of heat can damage the PBT material, which greatly improves the yellowing degree of the lamp housing (plastic housing).

Anti-yellowing PBT special material for energy-saving lamps with cover of the present invention——anti-yellowing enhanced flame-retardant polybutylene terephthalate (PBT) The glass fiber in the composition generally selects alkali-free glass fiber, which is used for Reinforcement of thermoplastics.

The anti-yellowing PBT special material for energy-saving lamps with hoods of the present invention—the anti-yellowing enhanced flame-retardant polybutylene terephthalate (PBT) composition, most of the anti-ultraviolet agents are benzotriazoles, Such as 2-(2-hydroxy-5-tert-octylphenylbenzo)triazole, 2-(2H-benzotriazol-2-yl)-4,6 bis(1-methyl-1-phenyl Ethyl)phenol, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, etc. All light stabilizers and complexes suitable for polyester compound.

Anti-yellowing PBT special material for energy-saving lamps with cover of the present invention—anti-yellowing enhanced flame-retardant polybutylene terephthalate (PBT) composition. , 5-di-tert-butyl-4-hydroxybenzyl) propionate (such as Ciba Irganox1010), ethylene glycol (β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), 3,5 diphosphite tris((2,4-di-tert-butylphenyl) ester (such as Ciba Irganox168), etc., and their complexes in various proportions (such as Ciba's IrganoxB215, B225). For To enhance the antioxidant effect, you can also add: such as Irganox259, 4,4'-thiobis(6-tert-butyl-3-methylphenol) (such as Guangzhou Hecai Institute Antioxidant 300), etc.

The whitening agent used in the anti-yellowing PBT plastic shell special material for energy-saving lamps with a cover of the present invention—the anti-yellowing enhanced flame-retardant polybutylene terephthalate (PBT) composition mainly includes titanium dioxide, OB ( 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene), OB-1 (2,2-dibenzoxazole) and the like. Because the plastic shells of energy-saving lamps are basically fluorescent white, these brighteners are generally required to be added according to customer requirements. In the field of energy-saving lamps, customers have almost strict requirements on color.

Some light-shielding agents must also be added in the anti-yellowing PBT plastic case special material for energy-saving lamps with hoods of the present invention—anti-yellowing enhanced flame-retardant polybutylene terephthalate (PBT) composition, such as zinc oxide, carbonic acid, etc. Calcium, barium sulfate, bauxite, clay and many other inorganic powders, considering the particularity of the color of the energy-saving lamp industry, the present invention generally uses zinc oxide with a blue-white phase is more ideal.

The anti-yellowing PBT plastic case special material for energy-saving lamps with shades of the present invention is the anti-yellowing enhanced flame-retardant polybutylene terephthalate (PBT) composition, and a toughening agent is added when high mechanical properties are required. Typical ones are: a series of copolymers containing epoxy functional groups, acrylate-containing core-shell tougheners, acrylate-containing copolymers or EPDM grafted maleic anhydride, etc., and their complexes.

The preparation method of the anti-yellowing PBT plastic shell special material for energy-saving lamps with hoods of the present invention—the anti-yellowing enhanced flame-retardant polybutylene terephthalate (PBT) composition is as follows: first polybutylene terephthalate Glycol ester PBT is baked at 120-150°C for 2-5 hours, and the moisture content is controlled to be <0.05% to prevent the decomposition of PBT resin during high-temperature processing, and then compounded with flame retardants, antioxidants, anti-ultraviolet agents, and sunscreens. , toughening agent, etc. are mixed by a mixer or separately from the metering feeder into the twin-screw extruder, fully plasticized and melted, then a certain amount of alkali-free glass fiber is added, and then extruded, drawn, cooled, Diced, homogenized and packaged. The aspect ratio of the twin-screw extruder used in the compound preparation method of the present invention is at least 32, and has precise temperature control and vacuum exhaust equipment, the vacuum degree is > 0.05Mpa, and the temperature of each section is controlled at 200-270 between ℃.

The invention has a reasonable formula and excellent anti-yellowing performance.

Detailed ways:

The present invention will be further described below in conjunction with embodiment.

Detailed ways:

Example 1: First bake polybutylene terephthalate (PBT) at 120-150°C for 2-5 hours, control the moisture content <0.05%, and then mix it with a composite flame retardant (pentabromobenzyl polyacrylate , brominated epoxy resin, brominated polycarbonate, mixture of antimony trioxide), compound antioxidant, anti-ultraviolet agent (ie, ultraviolet absorber 2-(2-hydroxy-5-tert-octylphenyl) Benzotriazole, 2-(2H-benzotriazol-2-yl)-4,6 bis(1-methyl-1-phenylethyl)phenol, 2-(2'-hydroxy-3'- One or several complexes of tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole), opacifier, toughening agent (methacrylate glycidyl ester copolymer) Mixed by a mixer or separately from a metering feeder into a twin-screw extruder, plasticized and melted, then added with glass fiber, and then extruded, drawn, cooled, pelletized, homogeneously mixed, and packaged to obtain the product. The twin-screw extruder has an aspect ratio of at least 32, is equipped with temperature control and vacuum exhaust equipment, the vacuum degree is >0.05Mpa, and the temperature of each section is controlled between 200-270°C. Each component and consumption (percentage by weight) are shown in Table 1.

Embodiment 2: production method is the same as embodiment 1, and each component and consumption (percentage by weight) are shown in Table 1.

It can be seen that the total color difference ΔE of the above case is much smaller than that of ordinary energy-saving lamp materials after 20 days of lighting by the customer. The special material for yellowing-resistant PBT plastic shells of energy-saving lamps with hoods in the present invention: yellowing-resistant enhanced flame-retardant polybutylene terephthalate The glycol ester (PBT) composition is far better than the common PBT energy-saving lamp materials on the market, and has excellent anti-yellowing effect.

Each component in the above-mentioned embodiment of the present invention can be changed to some extent, for example: composite flame retardant is made up of flame retardant A, flame retardant B and flame retardant C compound, wherein flame retardant A is polyacrylic acid pentabromobenzyl Ester, flame retardant B is brominated epoxy resin or brominated polycarbonate, and flame retardant C is antimony trioxide; the weight ratio of flame retardant A, flame retardant B, and flame retardant C is: 5-10: 5-10: 1-5.

The toughening agent is a series of copolymers containing epoxy functional groups, core-shell toughening agents containing acrylates, copolymers containing acrylates, and one or more complexes of EPDM grafted maleic anhydride.

Sunscreens are zinc oxide, calcium carbonate, barium sulfate, alumina or clay.

The anti-ultraviolet agent is 2-(2-hydroxy-5-tert-octylphenyl) benzotriazole, 2-(2H-benzotriazol-2-yl)-4,6 bis(1-methyl-1 One or several complexes of -phenylethyl)phenol, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole .

Antioxidants are pentaerythritol tetrakis 3-(3,5-di-tert-butyl-4-hydroxybenzyl) propionate, ethylene glycol (β-(3,5-di-tert-butyl-4-hydroxyphenyl) propane ester), 3,5 diphosphite tris((2,4-di-tert-butylphenyl)ester, Irganox259, 4,4'-thiobis(6-tert-butyl-3-methylphenol) Several compounds.

Whitening agents can also be added: titanium dioxide, 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene or 2,2-dibenzoxazole.

Claims (6)

1. the band cover electricity-saving lamp PBT of anti-the xanthochromia moulds the shell PP Pipe Compound, it is characterized in that: mainly be made up of following components in weight percentage:

Wherein composite flame-retardant agent is by fire retardant A, fire retardant B and fire retardant C is compound forms; Wherein fire retardant A is a ROHM pentabromo-benzyl ester; Fire retardant B is brominated epoxy resin or brominated polycarbonate, and fire retardant C is Antimony Trioxide: 99.5Min or zinc borate or the mixture of the two; Fire retardant A, fire retardant B, fire retardant C three's weight ratio is: 5～10: 5～10: 1～5;

Said opalizer is zinc oxide, lime carbonate, permanent white, alum clay or clay;

Said anti ultraviolet agent is one or more the compound in 2-(2-hydroxyl-uncle's 5-octyl phenyl) benzotriazole, 2-(2H-benzotriazole-2-yl)-4,6 two (1-methyl isophthalic acid-phenylethyl) phenol, 2-(2 '-hydroxyl-the 3 '-tertiary butyl-5 '-the aminomethyl phenyl)-5-chlorinated benzotriazole;

Said oxidation inhibitor is tetramethylolmethane four 3-(3; 5-di-t-butyl-4 hydroxybenzyl) propionic ester, terepthaloyl moietie (β-(3; The 5-di-tert-butyl-hydroxy phenyl) propionic ester), 3; 5 diphosphorous acids three ((2, the 4-di-tert-butyl-phenyl) ester, Irganox259,4,4 '-thiobis (the 6-tertiary butyl-3-methylphenol) is several kinds compound wherein;

The said band cover electricity-saving lamp PBT of anti-the xanthochromia moulds the shell PP Pipe Compound and is processed by working method: earlier polybutylene terephthalate was dried by the fire 2-5 hour down at 120-150 ℃; Control moisture content＜0.05%; Mix through mixer with composite flame-retardant agent, oxidation inhibitor, anti ultraviolet agent, opalizer, toughner subsequently or distinguish separately and get into twin screw extruder from the metering feeding device; Plasticizing, add spun glass after the fusion, again through extrude, tie rod, cooling, pelletizing, all mix, pack product.

2. the band cover electricity-saving lamp PBT of anti-xanthochromia the according to claim 1 moulds the shell PP Pipe Compound, and it is characterized in that: spun glass is an alkali free glass fibre.

3. the band cover electricity-saving lamp PBT of anti-xanthochromia the according to claim 1 moulds the shell PP Pipe Compound, it is characterized in that: toughner is one or more the compound in the series copolymer that contains epoxy-functional, the nucleocapsid toughner that contains propenoate, the multipolymer that contains propenoate, the EPDM grafted maleic anhydride.

4. mould the shell PP Pipe Compound according to claim 1, the 2 or 3 described band cover electricity-saving lamp PBT of anti-the xanthochromia; It is characterized in that: also be added with whitening agent: white titanium pigment, 2; Two (the 5-tertiary butyl-2-benzoxazolyl) thiophene or 2 of 5-, the compound of one or more in the 2-Er benzoxazole.

5. the described band cover of the claim 1 electricity-saving lamp PBT of anti-the xanthochromia moulds the working method of shell PP Pipe Compound; It is characterized in that: earlier polybutylene terephthalate was dried by the fire 2-5 hour down at 120-150 ℃; Control moisture content＜0.05%; Mix through mixer with composite flame-retardant agent, oxidation inhibitor, anti ultraviolet agent, opalizer, toughner subsequently or distinguish separately and get into twin screw extruder from the metering feeding device; Plasticizing, add spun glass after the fusion, again through extrude, tie rod, cooling, pelletizing, all mix, pack product; Said opalizer is zinc oxide, lime carbonate, permanent white, alum clay or clay; Said anti ultraviolet agent is one or more the compound in 2-(2-hydroxyl-uncle's 5-octyl phenyl) benzotriazole, 2-(2H-benzotriazole-2-yl)-4,6 two (1-methyl isophthalic acid-phenylethyl) phenol, 2-(2 '-hydroxyl-the 3 '-tertiary butyl-5 '-the aminomethyl phenyl)-5-chlorinated benzotriazole; Said oxidation inhibitor is tetramethylolmethane four 3-(3; 5-di-t-butyl-4 hydroxybenzyl) propionic ester, terepthaloyl moietie (β-(3; The 5-di-tert-butyl-hydroxy phenyl) propionic ester), 3; ((2, the 4-di-tert-butyl-phenyl) ester, Irganox259,4,4 '-thiobis (the 6-tertiary butyl-3-methylphenol) is several kinds compound wherein for 5 diphosphorous acids three.

6. the band cover electricity-saving lamp PBT of anti-xanthochromia the according to claim 5 moulds the working method of shell PP Pipe Compound; It is characterized in that: the length-to-diameter ratio of said twin screw extruder is at least 32; And have temperature control and vacuum-pumping equipment, and vacuum tightness＞0.05Mpa, each section temperature is controlled between 200-270 ℃.