A lubricant, a light-transmitting polycarbonate composite material and a preparation method thereof

Abstract

The present invention provides a lubricant, a light-transmitting polycarbonate composite material, and a preparation method thereof. The lubricant is obtained by polymerizing a dihydroxy compound and a carbonic acid diester compound, and the dihydroxy compound includes a compound having a structure represented by Formula I and a compound having a structure represented by Formula II. By selecting a dihydroxy compound and a carbonic acid diester compound of specific structures for polymerization, the obtained lubricant has excellent lubricating properties. When used in the processing of polycarbonate resin, it can effectively improve the processing properties of the obtained light-transmitting polycarbonate composite material, and can also enable the final light-transmitting polycarbonate composite material to have excellent mechanical properties, heat resistance, and optical properties, making it very suitable for use in high-end optical equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of lubricants, and in particular relates to a lubricant, a light-transmitting polycarbonate composite material and applications thereof. Background Art

[0002] Polycarbonate refers to a class of polymers whose macromolecular chains are composed of repeating carbonate-type structural units. It exhibits excellent overall performance and is an important engineering plastic with a wide range of applications in automotive parts, electronics / electrical products, household goods, and optical media. The use of lubricants in the processing and application of polycarbonate can significantly improve both its processing characteristics and the performance of the final product. Currently, a wide variety of lubricants are used for polycarbonate, including common ones such as polyester lubricants, silicone lubricants, mineral oils, and special-purpose lubricants. These lubricants primarily function to reduce friction, improve fluidity, prevent mold adhesion, and enhance the surface quality of finished products.

[0003] However, commonly used lubricants currently on the market present various issues that can affect the performance of polycarbonate composites. Some existing lubricants exhibit poor compatibility with polycarbonate, leading to phase separation or migration during processing and use. This can reduce mechanical properties such as tensile and flexural strength, as well as heat resistance, of the resulting polycarbonate composites. It can also reduce the light transmittance and gloss of the polycarbonate itself. For example, CN115491016A discloses a self-lubricating polycarbonate reinforced composite material, its preparation method and application. The self-lubricating polycarbonate reinforced composite material comprises the following components by weight: 100 parts of polycarbonate; 8-40 parts of glass fiber; 5-15 parts of polytetrafluoroethylene; 0.2-1 part of a silane coupling agent; and 0.2-1 part of a processing aid. The preparation method comprises uniformly mixing the components, melt-extruding and granulating the components at a temperature of 270-290°C through a twin-screw extruder to obtain the self-lubricating polycarbonate reinforced composite material. The prepared self-lubricating polycarbonate reinforced composite material has excellent surface smoothness and can be widely used in the preparation of plastic products. However, the polytetrafluoroethylene added in the invention will cause the light transmittance of the material to decrease, and it cannot be used in the field of high-end optics.

[0004] Some existing lubricants may undergo chemical reactions or deteriorate under conditions of high temperature, high humidity or chemical environment, reducing their lubrication performance, or may require complex processing or be effective under specific conditions during use, increasing the difficulty and cost of the processing technology; and under some high temperature, high load or high speed working conditions, a single lubricant may not be able to meet the lubrication needs of polycarbonate, or its lubrication effect will gradually decrease over time.

[0005] Therefore, in response to the above technical problems, there is an urgent need to develop a lubricant that has good lubrication effect and does not affect the excellent mechanical properties, optical properties and heat resistance of the polycarbonate resin itself. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the present invention aims to provide a lubricant, a light-transmitting polycarbonate composite material and a preparation method thereof. The lubricant has an excellent lubricating effect, can effectively improve the processing performance of the polycarbonate resin, and will not affect its excellent mechanical properties, optical properties and heat resistance. The final light-transmitting polycarbonate resin can have both excellent mechanical properties and heat resistance, while also having a suitable melt index, high light transmittance, low haze and high refractive index.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a lubricant obtained by polymerizing a dihydroxy compound and a carbonate diester compound;

[0009] The dihydroxy compound includes a compound having a structure shown in Formula I and a compound having a structure shown in Formula II:

[0010] Formula I;

[0011] In formula I, R1 and R2 are each independently selected from H, C1~C20 (e.g., C1, C2, C4, C6, C8, C10, C12, C14, C16, C18 or C20, etc.) straight or branched alkyl, C3~C20 (e.g., C3, C5, C7, C9, C11, C13, C15, C17 or C20, etc.) cycloalkyl, C1~C20 (e.g., C1, C2, C4, C6, C8, C10, C12, C14, C16, C18 or C20, etc.) any one of a C4-C16, C18 or C20 (e.g., C16, C18 or C20) straight-chain or branched alkoxy group, a C3-C20 (e.g., C4, C5, C7, C9, C11, C13, C15, C17 or C20) cycloalkoxy group, a C6-C20 (e.g., C6, C9, C12, C15, C17, C19 or C20) aryl group or a C6-C20 (e.g., C6, C9, C12, C15, C17, C19 or C20) aryloxy group;

[0012] Formula II;

[0013] In formula II, X is selected from any one of a C1-C6 (e.g., C1, C2, C4, or C6) linear or branched alkylene group, and a C3-C6 (e.g., C3, C4, C5, or C6) cycloalkylene group;

[0014] R3 and R4 are each independently selected from H, C1~C20 (e.g. C1, C2, C4, C6, C8, C10, C12, C14, C16, C18 or C20, etc.) straight or branched alkyl, C5~C20 (e.g. C5, C6, C8, C10, C12, C14, C16, C18 or C20, etc.) cycloalkyl, C1~C20 (e.g. C1, C2, C4, C6, C8, C10, C12, C14, Any one of a C5~C20 (e.g., C5, C6, C8, C10, C12, C14, C16, C18, or C20, etc.) straight-chain or branched alkoxy group, a C5~C20 (e.g., C5, C6, C8, C10, C12, C14, C16, C18, or C20, etc.) cycloalkoxy group, a C6~C20 (e.g., C6, C9, C12, C15, C17, C19, or C20, etc.) aryl group, or a C6~C20 (e.g., C6, C9, C12, C15, C17, C19, or C20, etc.) aryloxy group;

[0015] L is selected from any one of a C1-C8 (e.g., C1, C2, C4, C6, or C8) linear or branched alkylene group, a C3-C20 (e.g., C3, C5, C6, C8, C10, C12, C14, C16, C18, or C20) cycloalkylene group, a C6-C20 (e.g., C6, C9, C12, C15, C17, C19, or C20) arylalkyl group, or a C6-C20 (e.g., C6, C9, C12, C15, C17, C19, or C20) diarylalkyl group;

[0016] n is any integer from 0 to 5 (eg, 1, 2, 3, 4, or 5).

[0017] The lubricant provided by the present invention is obtained by polymerizing a dihydroxy compound and a carbonate diester compound, and the dihydroxy compound is limited to include a compound having a structure represented by Formula I and a compound having a structure represented by Formula II. The above three compounds are selected as raw materials in combination, so that the obtained lubricant not only has an excellent and long-lasting lubricating effect, but also can effectively improve the processing performance of polycarbonate resin, and will not affect the excellent mechanical properties, optical properties and heat resistance of the polycarbonate resin itself. The final translucent polycarbonate composite material can have both excellent mechanical properties and heat resistance, and also has a suitable melt index, a high refractive index, a high light transmittance and a low haze.

[0018] Preferably, the compound having the structure shown in Formula I is any one of the following dihydroxy compounds A1 to A3:

[0019] 、 、 .

[0020] Preferably, L is selected from C1~C8 straight or branched alkylene, C3~C20 cycloalkylene, Any one of the foregoing, wherein R5 and R6 are each independently selected from H, C1-C5 (e.g., C1, C2, C3, C4, or C5) linear or branched alkyl groups, and “·” represents a connection site.

[0021] Preferably, the compound having the structure shown in Formula II is bisphenol fluorene or bisether fluorene.

[0022] Among them, the structural formula of bisether fluorene is: .

[0023] The structural formula of bisphenol fluorene is: .

[0024] Preferably, the carbonic acid diester compound includes any one of diphenyl carbonate, ditolyl carbonate, dimethyl carbonate or diethyl carbonate, or a combination of at least two thereof, and more preferably diphenyl carbonate.

[0025] Preferably, the molar ratio of the carbonic acid diester compound, the compound having the structure represented by Formula I and the compound having the structure represented by Formula II is (1-2):(1-1.8):1, for example, 1:1:1, 1.2:1:1, 1.5:1:1, 1.8:1:1, 2:1:1, 1.5:1.2:1, 1.5:1.4:1, 1.5:1.6:1 or 1.5:1.8:1, etc.

[0026] Preferably, the weight-average molecular weight of the lubricant is 500-4000, for example, 500, 800, 1000, 1200, 1400, 1600, 1800, 2000, 2500, 3000, 3400 or 3800, and more preferably 1000-3500. If the weight-average molecular weight of the lubricant is too low, its lubrication effect is relatively poor, especially under high temperature, high load or high speed working conditions, it may not meet the lubrication requirements of the polycarbonate resin. If the weight-average molecular weight of the lubricant is too high, its lubrication effect may be limited. Lubricants with relatively high molecular weight have relatively long molecular chains and may form a thicker lubricating layer in the polymer melt, but the fluidity of such a lubricating layer may be poor. In addition, lubricants with relatively high molecular weight may be difficult to disperse evenly in the polymer melt, resulting in insufficient local lubrication.

[0027] Preferably, the molecular weight distribution index of the lubricant is 1 to 4, for example, 1, 1.5, 2, 2.5, 3, 3.5 or 4.

[0028] In a second aspect, the present invention provides a method for preparing the lubricant as described in the first aspect, the preparation method comprising: subjecting a dihydroxy compound and a carbonate diester compound to a polymerization reaction to obtain the lubricant.

[0029] Preferably, the polymerization reaction is carried out in the presence of a catalyst.

[0030] Preferably, the molar ratio of the carbonic acid diester compound to the catalyst is (1-2): 0.6×10 -5 , for example 1:0.6×10 -5 , 1.2:0.6×10 -5 , 1.4:0.6×10 -5 , 1.6:0.6×10 -5 , 1.8:0.6×10 -5 or 2:0.6×10 -5 wait.

[0031] Preferably, the catalyst comprises any one or a combination of at least two of lithium acetate, sodium acetate, magnesium acetate, potassium acetate, calcium acetate, strontium acetate, barium acetate, sodium stearate, magnesium stearate, potassium stearate, calcium stearate, lithium benzoate, sodium benzoate, potassium benzoate, calcium benzoate, cesium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, disodium phenyl phosphate, magnesium phenyl phosphate, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylbenzylammonium hydroxide, diethylamine, triethylamine, dimethylbenzylamine, triphenylamine, tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, tetraphenylammonium tetraphenylborate, lithium hydroxide, sodium hydroxide, magnesium hydroxide, potassium hydroxide, calcium hydroxide, cesium hydroxide, strontium hydroxide, barium hydroxide, sodium bicarbonate, magnesium bicarbonate, sodium carbonate, magnesium carbonate or potassium carbonate, and more preferably sodium hydroxide and / or sodium bicarbonate.

[0032] Preferably, the polymerization reaction includes the steps of first reacting at 165-185°C (for example, 165°C, 170°C, 175°C, 180°C or 185°C, etc.) and 50-101.4 kPa (for example, 50 kPa, 55 kPa, 60 kPa, 70 kPa, 80 kPa, 90 kPa or 100 kPa, etc.) for 80-120 min (for example, 80 min, 90 min, 100 min, 110 min or 120 min, etc.), then heating to 190-210°C (for example, 190°C, 195°C, 200°C, 205°C or 210°C, etc.) and reducing the pressure to 22-32 kPa (for example, 22 kPa, 25 kPa, 28 kPa or 32 kPa, etc.) for 15-45 min (for example, 15 min, 25 min, 35 min or 45 min, etc.).

[0033] In a third aspect, the present invention provides a light-transmitting polycarbonate composite material, comprising a polycarbonate resin and the lubricant according to the first aspect.

[0034] Preferably, the light-transmitting polycarbonate composite material comprises the following components in parts by weight:

[0035] 94-99.2 parts by weight of polycarbonate resin;

[0036] 0.5-7 parts by weight of the lubricant as described in the first aspect.

[0037] The polycarbonate resin may be used in an amount of 94 parts by weight, 94.5 parts by weight, 95 parts by weight, 95.5 parts by weight, 96 parts by weight, 96.5 parts by weight, 97 parts by weight, 98 parts by weight, 98.5 parts by weight or 99 parts by weight.

[0038] The amount of the lubricant can be 0.8 parts by weight, 1 part by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, 3.5 parts by weight, 4 parts by weight, 4.5 parts by weight or 5 parts by weight, etc.

[0039] Preferably, the content of the lubricant in the light-transmitting polycarbonate composite material is 0.8 to 6 parts by weight. If the amount of the lubricant added is too high, the heat resistance of the obtained light-transmitting polycarbonate composite material will decrease, and it will be more easily decomposed during processing. If the amount of the lubricant added is too low, the processing performance of the obtained light-transmitting polycarbonate composite material will be limited.

[0040] Preferably, the weight average molecular weight of the polycarbonate resin is ≥15,000, for example, 15,000, 18,000, 20,000, 25,000, 30,000, 40,000 or 50,000.

[0041] Preferably, the polycarbonate resin has a glass transition temperature (Tg) of 80-160°C, for example, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 150°C, or 160°C.

[0042] Preferably, the polycarbonate resin has a melt volume flow rate of 30 to 60 cm2 when tested at 260°C and 2.16 kg. 3 / 10min, for example 30cm 3 / 10min、35cm 3 / 10min、40cm 3 / 10min、45cm 3 / 10min、50cm 3 / 10min、55cm 3 / 10min or 60cm3 / 10min, etc.

[0043] Preferably, the raw material for preparing the polycarbonate resin is the same as the raw material for preparing the lubricant.

[0044] In the present invention, the raw materials for preparing the polycarbonate resin and the raw materials for preparing the lubricant are the same, which means that the types of raw materials used for both are the same, that is, the polycarbonate resin is also obtained by polymerizing a dihydroxy compound having a structure represented by Formula I, a dihydroxy compound having a structure represented by Formula II, and a carbonic acid diester compound, and the specific types of the selected dihydroxy compound and carbonic acid diester compound are also the same, but the molar ratio between the raw materials and the preparation method (including parameters such as reaction temperature, pressure and time) may be different; this can ensure that the polycarbonate resin and the lubricant have better compatibility, and can further improve the optical properties, mechanical properties and heat resistance of the obtained light-transmitting carbonate composite material.

[0045] In the present invention, the preparation method of the polycarbonate resin is not particularly limited, and the polycarbonate resin can be prepared by referring to the preparation method of the lubricant or by conventional methods in the art.

[0046] Preferably, the light-transmitting polycarbonate composite material further comprises an antioxidant.

[0047] Preferably, the content of the antioxidant in the light-transmitting polycarbonate composite material is 0.3 to 0.5 parts by weight, for example, 0.3 parts by weight, 0.32 parts by weight, 0.34 parts by weight, 0.36 parts by weight, 0.38 parts by weight, 0.4 parts by weight, 0.42 parts by weight, 0.44 parts by weight, 0.46 parts by weight, 0.48 parts by weight or 0.5 parts by weight, etc.

[0048] Preferably, the antioxidant includes antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), antioxidant 1076 (octadecylβ-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), antioxidant 1135 (isooctanolβ-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), antioxidant 1520 (2,4-bis(n-octylthiomethylene)- Any one of antioxidant 702 (4,4'-methylenebis(2,6-di-tert-butyl-4-methylphenol)), antioxidant 1330 (1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene), or antioxidant 1035 (2,2'-thiobis[ethyl 3-(3,5-di-tert-butyl-4-hydroxybenzyl)propionate]), or a combination of at least two thereof.

[0049] In addition, in the present invention, other additives may be added to the light-transmitting polycarbonate composite material as needed, including but not limited to any one or a combination of at least two of dyes, bluing agents, flame retardants, release agents, ultraviolet absorbers, crystallization nucleating agents, reinforcing agents, antistatic agents or antibacterial agents.

[0050] In a fourth aspect, the present invention provides a method for preparing the light-transmitting polycarbonate composite material as described in the third aspect, the preparation method comprising: mixing the components, extruding and granulating to obtain the light-transmitting polycarbonate composite material.

[0051] Preferably, the mixing temperature is 20-40°C, for example, 20°C, 22°C, 24°C, 26°C, 28°C, 30°C, 32°C, 34°C, 36°C, 38°C or 40°C.

[0052] Preferably, the mixing time is 10 to 40 min, for example, 10 min, 15 min, 20 min, 25 min, 30 min, 35 min or 40 min.

[0053] Preferably, the mixing speed is 300-800 rpm, for example, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm or 800 rpm.

[0054] Preferably, the extrusion and granulation are carried out in a twin-screw extruder.

[0055] Preferably, the temperature of each working zone in the twin-screw extruder is: the temperature of zone 1 is 220-230°C (for example, 220°C, 222°C, 224°C, 226°C, 228°C or 230°C), the temperature of zone 2 is 230-240°C (for example, 230°C, 232°C, 234°C, 236°C, 238°C or 240°C), and the temperature of zone 3 is 250-260°C (for example, 250°C, 252°C, 254°C, 256°C, 258°C or 260°C). The temperatures of zones four and five are each independently 255-260°C (for example, 255°C, 256°C, 257°C, 258°C, 259°C or 260°C), the temperatures of zones six and seven are each independently 245-255°C (for example, 245°C, 247°C, 249°C, 251°C, 253°C or 255°C), and the temperatures of zones eight and nine are each independently 240-250°C (for example, 240°C, 242°C, 244°C, 246°C, 248°C or 250°C).

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] The lubricant provided by the present invention is obtained by polymerizing a dihydroxy compound and a carbonic acid diester compound, and the dihydroxy compound includes a compound having a structure represented by Formula I and a compound having a structure represented by Formula II. By selecting a dihydroxy compound and a carbonic acid diester compound of specific structures for polymerization, the obtained lubricant has excellent lubricating properties. When used in the processing of polycarbonate resin, it can effectively improve the processing properties of the obtained light-transmitting polycarbonate composite material, and can also enable the final light-transmitting polycarbonate composite material to have excellent mechanical properties, heat resistance and optical properties. It is very suitable for use in high-end optical equipment, for example, it can be used in the preparation of optical lenses, optical devices, display screens or optical fiber communications. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is the molecular weight distribution diagram of the light-transmitting polycarbonate composite material provided in Application Example 1. DETAILED DESCRIPTION

[0059] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0060] Unless otherwise specified, the raw materials involved in the following specific embodiments are all conventional substances in the art and can be obtained by purchasing commercial products.

[0061] Preparation Example 1

[0062] A dihydroxy compound A1, whose structural formula is as follows:

[0063] ;

[0064] The preparation method of the dihydroxy compound A1 provided in Preparation Example 1 comprises the following steps:

[0065] (1) 12.1 g of p-benzoquinone and 10 g of anthracene were mixed and dissolved in 100 mL of anhydrous toluene. The mixture was refluxed for 4 h. The reaction solution was then cooled to room temperature. The precipitated solid was collected by filtration and washed with 10 mL of toluene. The mixture was then dried in a vacuum oven overnight to obtain a crude product. The crude product was then dissolved in 350 mL of acetic acid solution, and a 48% by weight hydrobromic acid solution was added dropwise. A white solid was immediately precipitated. The white solid was washed with 15 mL of acetic acid and 30 mL of n-hexane and then dried to obtain an intermediate product Z1.

[0066] The structural formula of the intermediate product Z1 obtained in step (1) is as follows:

[0067] ;

[0068] (2) 286 g of the intermediate product Z1 obtained multiple times in step (1) and 176 g of ethylene carbonate were dissolved in 1 L of N,N-dimethylformamide, and 6.91 g of potassium carbonate was added as a catalyst. The mixture was heated under reflux for 10 h. After the reaction was completed, the mixture was cooled to room temperature, water was added, and the mixture was allowed to stand to precipitate a large amount of solid. The solid was then recrystallized and purified from 500 mL of 95% ethanol to obtain the dihydroxy compound A1.

[0069] Preparation Example 2

[0070] A dihydroxy compound A2, whose structural formula is as follows:

[0071] ;

[0072] The preparation method of the dihydroxy compound A2 provided in Preparation Example 2 comprises the following steps:

[0073] (1) 12.1 g of p-benzoquinone and 11.57 g of 2,6-dimethylanthracene were mixed and dissolved in 100 mL of anhydrous toluene. The mixture was refluxed for 4 h. The reaction solution was then cooled to room temperature. The precipitated solid was collected by filtration and washed with 10 mL of toluene. The mixture was then dried in a vacuum oven overnight to obtain a crude product. The crude product was then dissolved in 350 mL of acetic acid solution, and a 48% by weight hydrobromic acid solution was added dropwise. A white solid was immediately precipitated. The white solid was washed with 15 mL of acetic acid and 30 mL of n-hexane and then dried to obtain the intermediate product Z2.

[0074] The structural formula of the intermediate product Z2 obtained in step (1) is as follows:

[0075] ;

[0076] (2) 314 g of the intermediate product Z2 obtained multiple times in step (1) and 176 g of ethylene carbonate were dissolved in 1 L of N,N-dimethylformamide, and 6.91 g of potassium carbonate was added as a catalyst. The mixture was heated under reflux for 10 h. After the reaction was completed, the mixture was cooled to room temperature, and water was added and allowed to stand to precipitate a large amount of solid. The solid was then recrystallized and purified from 500 mL of 95% ethanol to obtain the dihydroxy compound A2.

[0077] Preparation Example 3

[0078] A polycarbonate resin having a weight-average molecular weight of 37,000, obtained by polymerizing diphenyl carbonate, dihydroxy compound A1 (Preparation Example 1), and bisether fluorene in a molar ratio of 1.5:1:1;

[0079] The preparation method of the polycarbonate resin provided in Preparation Example 3 comprises: adding diphenyl carbonate, dihydroxy compound A1 and bisether fluorene in the above molar ratio into a polymerization reaction kettle with an effective volume of 3 L, and then adding sodium hydroxide (the molar ratio of sodium hydroxide to diphenyl carbonate is 0.6×10 -5 :1.06) for melt polycondensation, the polymerization reaction is divided into the following four stages: first, the temperature in the kettle is raised to 170°C within 20 minutes, and the reaction is carried out for 10 minutes. Subsequently, the pressure in the kettle is reduced to 25 kPa within 5 minutes, and the reaction is continued for 30 minutes. The temperature in the kettle is raised to 210°C within 10 minutes, the pressure in the kettle is reduced to 15 kPa, and the reaction is continued for 20 minutes. The temperature in the kettle is raised to 240°C within 10 minutes, the pressure in the kettle is reduced to 5 kPa, and the reaction is continued for 20 minutes. The temperature in the kettle is raised to 260°C within 10 minutes, the pressure in the kettle is reduced to 0.1 kPa, and the reaction is continued for 60 minutes. After the reaction is completed, heating is stopped, nitrogen is introduced, and after the temperature is reduced to room temperature, an appropriate amount of tetrahydrofuran is added to dissolve the product, and the product is precipitated and separated in 1 L of anhydrous ethanol. The precipitated polymer is filtered, washed with ethanol multiple times, and vacuum-dried at 80°C for 8 hours to obtain the polycarbonate resin.

[0080] Preparation Example 4

[0081] A polycarbonate resin having a weight-average molecular weight of 32,000, obtained by polymerizing diphenyl carbonate, dihydroxy compound A2 (Preparation Example 2), and bisphenol fluorene in a molar ratio of 1.5:1:1;

[0082] The preparation method of the polycarbonate resin provided in Preparation Example 4 comprises: adding diphenyl carbonate, dihydroxy compound A2 and bisphenol fluorene according to the above molar ratio into a polymerization reaction kettle with an effective volume of 3 L, adding sodium hydroxide (the molar ratio of sodium hydroxide to diphenyl carbonate is 0.6×10 -5 :1.06) for melt polycondensation, the polymerization reaction is divided into the following four stages: first, the temperature in the kettle is raised to 170°C within 20 minutes, and the reaction is carried out for 10 minutes. Subsequently, the pressure in the kettle is reduced to 25 kPa within 5 minutes, and the reaction is continued for 30 minutes. The temperature in the kettle is raised to 210°C within 10 minutes, the pressure in the kettle is reduced to 15 kPa, and the reaction is continued for 20 minutes. The temperature in the kettle is raised to 240°C within 10 minutes, the pressure in the kettle is reduced to 5 kPa, and the reaction is continued for 20 minutes. The temperature in the kettle is raised to 260°C within 10 minutes, the pressure in the kettle is reduced to 0.1 kPa, and the reaction is continued for 60 minutes. After the reaction is completed, heating is stopped, nitrogen is introduced, and after the temperature is reduced to room temperature, an appropriate amount of tetrahydrofuran is added to dissolve the product, and the product is precipitated and separated in 1 L of anhydrous ethanol. The precipitated polymer is filtered, washed with ethanol multiple times, and vacuum-dried at 80°C for 8 hours to obtain the polycarbonate resin.

[0083] Example 1

[0084] A lubricant having a weight-average molecular weight of 2200, obtained by polymerizing diphenyl carbonate, dihydroxy compound A1 (Preparation Example 1), and bisether fluorene in a molar ratio of 1.5:1:1;

[0085] The preparation method of the lubricant provided in Example 1 comprises: adding the diphenyl carbonate, dihydroxy compound A1 and bisether fluorene in the above-mentioned molar ratio into a polymerization reactor with an effective volume of 3 L, and then adding sodium hydroxide (the molar ratio of sodium hydroxide to diphenyl carbonate is 0.6×10 -5 :1.06) for melt polycondensation, the polymerization reaction is carried out in two stages, the temperature of the first stage is 180°C, the reaction time is 100 min, and the reaction pressure is 101.325 kPa, the reaction temperature of the second stage is 200°C, the reaction time is 30 min, and the reaction pressure is reduced to 25 kPa. After the reaction is completed, heating is stopped, nitrogen is introduced, and the material is discharged while hot to obtain the lubricant.

[0086] Example 2

[0087] A lubricant having a weight-average molecular weight of 2000, obtained by polymerizing diphenyl carbonate, dihydroxy compound A2 (Preparation Example 2), and bisphenol fluorene in a molar ratio of 1.2:1:1;

[0088] The preparation method of the lubricant provided in Example 2 comprises: adding the diphenyl carbonate, dihydroxy compound A2 and bisphenol fluorene in the above-mentioned molar ratio into a polymerization reactor with an effective volume of 3 L, and then adding sodium bicarbonate (the molar ratio of bicarbonate to diphenyl carbonate is 0.6×10 -5 :1.06) for melt polycondensation, the polymerization reaction is carried out in two stages, the temperature of the first stage is 175°C, the reaction time is 120 min, and the reaction pressure is 101.325 kPa, the reaction temperature of the second stage is 205°C, the reaction time is 25 min, and the reaction pressure is reduced to 25 kPa. After the reaction is completed, heating is stopped, nitrogen is introduced, and the material is discharged while hot to obtain the lubricant.

[0089] Example 3

[0090] A lubricant, which differs from Example 1 in that the weight-average molecular weight of the obtained lubricant is 1500 by adjusting the reaction temperature of the first stage to 170°C, the reaction temperature of the second stage to 190°C, the reaction pressure to 30 kPa, and the reaction time to 20 min. Other raw materials and preparation methods are the same as those of Example 1.

[0091] Example 4

[0092] A lubricant, which differs from Example 1 in that the weight-average molecular weight of the obtained lubricant is 800 by adjusting the reaction temperature of the first stage to 170°C and the reaction time to 85 minutes, and adjusting the reaction temperature of the second stage to 190°C, the reaction pressure to 32 kPa, and the reaction time to 20 minutes. Other raw materials and preparation methods are the same as those of Example 1.

[0093] Example 5

[0094] A lubricant, which differs from Example 1 in that the weight-average molecular weight of the obtained lubricant is 3600 by adjusting the reaction temperature of the first stage to 185°C and the reaction time to 120 min, and the reaction temperature of the second stage to 210°C, the reaction pressure to 32 kPa, and the reaction time to 45 min. Other raw materials and preparation methods are the same as those of Example 1.

[0095] Example 6

[0096] A lubricant is prepared, which differs from Example 1 only in that the dihydroxy compound A2 provided in Preparation Example 2 is used in an equal molar amount to replace the dihydroxy compound A1 provided in Preparation Example 1, and other raw materials and preparation methods are the same as those in Example 1.

[0097] Comparative Example 1

[0098] A lubricant is prepared from diphenyl carbonate and dihydroxy compound A1 (Preparation Example 1) in a molar ratio of 1.5:2. Other raw materials and preparation methods are the same as those in Example 1.

[0099] Comparative Example 2

[0100] A lubricant is provided, which differs from Example 1 in that it is obtained only by polymerizing diphenyl carbonate and bisetherfluorene in a molar ratio of 1.5:2, and other raw materials and preparation methods are the same as those in Example 1.

[0101] Application Examples 1 to 12

[0102] Application Examples 1 to 12 respectively provide a light-transmitting polycarbonate composite material, the components of which are shown in Table 1. In Table 1, the units of the amounts of the components are all in parts by weight.

[0103] Table 1

[0104]

[0105] In Table 1, “ / ” indicates that no addition was made.

[0106] The preparation method of the light-transmitting polycarbonate composite material provided in Application Examples 1 to 12 includes: mixing a polycarbonate resin, a lubricant, and an antioxidant at room temperature and a rotation speed of 500 rpm for 30 minutes, extruding and granulating through a twin-screw extruder, wherein the operating temperature of each zone of the twin-screw extruder is: the temperature of zone 1 is 230°C, the temperature of zone 2 is 240°C, the temperature of zone 3 is 260°C, the temperatures of zones 4 and 5 are both 260°C, the temperatures of zones 6 and 7 are both 255°C, the temperatures of zones 8 and 9 are both 250°C, and the screw speed is 350 rpm, thereby obtaining the light-transmitting polycarbonate composite material.

[0107] Comparative Application Example 1

[0108] A light-transmitting polycarbonate composite material is disclosed. The difference between the light-transmitting polycarbonate composite material and application example 1 is that no lubricant is added, and other substances, amounts used, and preparation methods are the same as those in application example 1.

[0109] Comparative Application Example 2

[0110] A light-transmitting polycarbonate composite material is disclosed, which differs from Application Example 1 in that an equal amount of glyceryl monostearate is used to replace the lubricant provided in Example 1, and other substances, amounts used, and preparation methods are the same as those in Application Example 1.

[0111] Comparative Application Example 3

[0112] A light-transmitting polycarbonate composite material is disclosed. The difference between the light-transmitting polycarbonate composite material and Application Example 1 is that an equal amount of the lubricant provided in Comparative Example 1 is used to replace the lubricant provided in Example 1. Other substances, amounts used, and preparation methods are the same as those in Application Example 1.

[0113] Comparative Application Example 4

[0114] A light-transmitting polycarbonate composite material is disclosed. The difference between the light-transmitting polycarbonate composite material and Application Example 1 is that the lubricant provided in Example 1 is replaced by an equal amount of the lubricant provided in Comparative Example 2, and other substances, amounts used, and preparation methods are the same as those in Application Example 1.

[0115] Performance testing:

[0116] (1) Polydispersity index: The light-transmitting polycarbonate composite material provided in Example 1 was tested using a gel permeation chromatograph. The molecular weight distribution of the light-transmitting polycarbonate composite material provided in Example 1 was obtained as shown in FIG. Figure 1 As shown;

[0117] from Figure 1 It can be seen that the lubricant and the polycarbonate resin in the light-transmitting polycarbonate composite material provided in Application Example 1 are very evenly dispersed, indicating that the two have good compatibility.

[0118] (2) Refractive index (1.0 mm sheet): The refractive index nD of the sample was measured at 25°C using an Abbe refractometer at a wavelength of 589 nm.

[0119] (3) Transmittance and haze: The haze was measured using a haze meter according to ASTM D1003, with a sample thickness of 0.1 mm.

[0120] (4) Melt index: The melt index is measured by INSTRON MFi5 at 260°C and 2.16 kg.

[0121] (5) Heat deformation temperature (HDT): The load bending temperature was measured using a heat deformation Vicat softening point temperature tester (WKT-VST300) in accordance with ISO 75-1 using an HDT test device under a load of 1.80 MPa (A method).

[0122] (6) Izod impact strength: tested using a GT-7045-HML plastic impact testing machine in accordance with the method provided in GB / T 1843-2008.

[0123] According to the above test methods (2) to (6), the light-transmitting polycarbonate composite materials provided in Examples 1 to 12 and Comparative Examples 1 to 4 were tested. The test results are shown in Table 2:

[0124] Table 2

[0125]

[0126] According to the data in Table 2, we can see that:

[0127] (1) The light-transmitting polycarbonate composite materials provided in Application Examples 1 to 12 have excellent processing properties, mechanical properties, heat resistance and optical properties.

[0128] (2) Comparing the data of Application Example 1 and Comparative Application Example 1, it can be seen that the melt index of the transparent polycarbonate composite material without adding lubricant is low, only 28.1cm 3 / 10min, indicating that its processing performance is poor, and its Izod impact strength is only 3.0kJ / m 2 , the mechanical properties are also poor.

[0129] (3) Comparing the data of Application Example 1 and Comparative Application Example 2, it can be seen that although the translucent polycarbonate composite material prepared by using glyceryl monostearate as a lubricant has a suitable melt index, its light transmittance is low, its refractive index is low, its haze is high, and its Izod impact strength is low, indicating that both the optical properties and mechanical properties have been significantly reduced.

[0130] (4) Comparing the data of Application Example 1 and Comparative Application Examples 3-4, it can be seen that the light-transmitting polycarbonate composite material prepared by using a lubricant obtained by polymerizing a single type of dihydroxy compound with diphenyl carbonate has a low light transmittance, a low refractive index, a high haze, and a low Izod impact strength, and also cannot have excellent processing performance, mechanical properties, heat resistance and optical properties.

[0131] (5) Further, by comparing the data of Application Example 1 and Application Examples 3 to 7, it can be seen that the processing performance and heat resistance of the obtained light-transmitting polycarbonate composite material can be adjusted by controlling the amount of lubricant added. When the amount of lubricant added is too low (Application Example 6), the melt index of the obtained polycarbonate composite material is still low, indicating that the improvement in processing performance is limited; when the amount of lubricant added is too high (Application Example 7), the heat resistance of the obtained light-transmitting polycarbonate composite material will be affected.

[0132] (6) Further comparison of the data of Application Example 1 and Application Examples 8 to 10 shows that when the weight-average molecular weight of the lubricant is too low (Example 9), low molecules will volatilize during processing, thereby losing the lubricating effect, resulting in a still low melt index of the obtained polycarbonate composite material; when the weight-average molecular weight of the lubricant is too high (Example 10), its lubricating effect may be limited. The high molecular weight lubricant has a longer molecular chain and may form a thicker lubricating layer in the polymer melt, but the fluidity of this lubricating layer may be poor, which will also result in a still low melt index of the obtained polycarbonate composite material.

[0133] (7) Further comparison of the data of Application Example 1 and Application Examples 11-12 shows that when the lubricant and polycarbonate resin are prepared from the same raw materials, the processing performance of the composite material can be further optimized without affecting the optics. When the lubricant and polycarbonate resin are prepared from mismatched raw materials, the optical performance will be reduced due to differences in the refractive index between the materials.

[0134] The applicant states that while the present invention uses the aforementioned embodiments to illustrate a lubricant, a light-transmitting polycarbonate composite material, and a method for preparing the same, the present invention is not limited to the aforementioned process steps, nor does it necessarily rely on the aforementioned process steps for implementation. Persons skilled in the art will appreciate that any improvements to the present invention, equivalent substitutions for the raw materials used, additions of auxiliary components, and selection of specific methods, etc., fall within the scope of protection and disclosure of the present invention.

Claims

1. A lubricant for polycarbonate resin, characterized in that: The lubricant is obtained by polymerizing a dihydroxy compound and a carbonic acid diester compound; The dihydroxy compound includes a compound having a structure shown in Formula I and a compound having a structure shown in Formula II: The compound having the structure shown in Formula I is the following dihydroxy compound A1 or A2: 、 ； The compound having the structure shown in Formula II is bisphenol fluorene or bisether fluorene; The raw materials for preparing the polycarbonate resin are the same as those for preparing the lubricant; The weight average molecular weight of the lubricant is 500-4000.

2. The lubricant according to claim 1, characterized in that The molar ratio of the carbonic acid diester compound, the compound having the structure represented by formula I and the compound having the structure represented by formula II is (1-2):(1-1.8):

1.

3. A method for preparing the lubricant according to claim 1 or 2, characterized in that: The preparation method comprises: performing a polymerization reaction on a dihydroxy compound and a carbonate diester compound to obtain the lubricant.

4. A light-transmitting polycarbonate composite material, characterized in that: The light-transmitting polycarbonate composite material comprises a polycarbonate resin and the lubricant according to claim 1 or 2.

5. The light-transmitting polycarbonate composite material according to claim 4, characterized in that: The light-transmitting polycarbonate composite material comprises the following components in parts by weight: 94-99.2 parts by weight of polycarbonate resin; 0.5-7 parts by weight of the lubricant according to claim 1 or 2.

6. A method for preparing the light-transmitting polycarbonate composite material according to claim 4 or 5, characterized in that: The preparation method comprises: mixing a polycarbonate resin and the lubricant according to claim 1 or 2, and obtaining the light-transmitting polycarbonate composite material by extrusion and granulation.

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