Silicon-containing processing aid for thermoplastic resin and preparation method thereof

Abstract

The present invention relates to the technical field of material processing, and discloses a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. The raw material components of the silicon-containing processing aid include modified polysiloxane, ultrahigh molecular weight polysiloxane, filler and additives; the structural formula of the modified polysiloxane is shown in the general formula (1): (1) The silicon-containing processing aid for thermoplastic resin provided by the present invention can improve the problems of die buildup and melt fracture of thermoplastic resin and its composite material during extrusion; can greatly improve the crystal point problem during film production; and further extend the screw cleaning cycle and equipment service life during processing of thermoplastic resin and its composite material, thereby improving production efficiency and product quality.

Description

Technical Field

[0001] The invention relates to the technical field of material processing, in particular to a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. Background Art

[0002] Thermoplastic resin materials have been widely used in people's lives due to their excellent physical and chemical properties, such as in automobile manufacturing, aerospace, daily life and other fields; at the same time, thermoplastic resins are easy to process and can be recycled, which can meet the purpose of circular economy. However, thermoplastic resin materials are generally polymer materials with a large molecular weight, which causes many problems, such as high processing temperature and difficulty in processing using twin-screw extrusion; thermoplastic resin materials have the viscoelasticity of polymer materials under high temperature conditions, which causes viscosity between them and metal processing equipment, resulting in processing problems such as carbon deposition inside the screw, material accumulation in the die, and melt fracture during extrusion. These problems will seriously affect the appearance and quality of the product, as well as production efficiency and the service life of the equipment.

[0003] The processing aids commonly used in the current industry include ultra-high molecular weight polysiloxane, polyethylene wax, polypropylene wax, stearate, fluorinated polymer processing aids (fluorinated PPA), etc.; among them, fluorinated PPA has the best use effect, and can effectively solve the problems of screw carbon deposition, die material accumulation, melt fracture, etc. with a very small addition amount. However, fluorinated compounds will produce small molecular fluorinated compounds during high-temperature processing. These fluorides will not be decomposed in the biological world and are bioaccumulative. At the same time, fluorides are seriously harmful to organisms and may be carcinogenic.

[0004] Polymer processing aids have been reported in the literature, most of which are fluorine-containing polymer processing aids, and there are also some modified polysiloxane polymer processing aids. For example, the patent with publication number CN101117393A discloses a multi-layer core-shell structured fluorine-containing polymer particle and a thermoplastic polyolefin product containing it, which has a fluorine-containing polymer as the core, an acrylate copolymer, a methacrylate copolymer or a mixture thereof as the middle layer, and a low melting point wax as the outermost layer, which can improve melt fracture and increase the critical shear rate during processing; this multi-layer core-shell structure material may experience shell separation at high temperature, and the fluorine-containing material is not environmentally friendly.

[0005] For example, the patent with publication number CN102286157A discloses a fluoropolymer processing aid, a silane cross-linked polyethylene composition containing the fluoropolymer, and its application. The fluoropolymer processing aid is prepared with a core-shell structure using a fluoropolymer as a core and an MQ silicone resin as a shell. The extrusion speed and surface finish of the product can be increased during the processing. However, the MQ silicone resin has the risk of cross-linking under high temperature conditions, and fluorinated substances are not environmentally friendly.

[0006] For example, the patent with publication number CN112812414A discloses a fluorosilicone polymer processing aid masterbatch and its preparation method, in which ultra-high molecular weight polysiloxane and fluoropolymer (fluoropolymer is a copolymer of caprolactone, fluoroelastomer and interfacial dispersant) and matrix resin are blended to prepare the processing aid masterbatch, which has fast onset and good yellowing resistance during processing and can effectively improve the processing performance of the polymer. However, the fluorine contained in the processing aid masterbatch is not environmentally friendly.

[0007] For example, the patent with publication number CN111087582A discloses a method for preparing a fluorine-containing polymer processing aid, in which the fluorine-containing polymer is dissolved in caprolactone, and then a polyol is added for copolymerization to obtain a blend of polyester wax and fluorine-containing polymer. During the processing, the extrusion pressure can be reduced, the processing efficiency can be improved, and the melt fracture and shark skin phenomenon during the polymer extrusion process can be improved. The preparation process of this patent is complicated, and the fluorine-containing polymer is not environmentally friendly and has a large impact on the environment.

[0008] For example, the patent with publication number CN117510816A discloses a polyester-modified branched polysiloxane processing aid and a preparation method thereof, wherein caprolactone, an initiator, a catalyst and a branched polysiloxane are added into a reaction kettle and stirred to carry out a polymerization reaction to obtain a polyester-modified branched polysiloxane processing aid, which can improve the fluidity of plastic processing, reduce torque, eliminate surface defects, effectively reduce die buildup during resin processing, and improve the quality of the resin; this patent is not easy to control, and the branched polysiloxane is prone to cross-linking reaction during the reaction process.

[0009] For example, the patent with publication number CN114381078A discloses a processing aid for thermoplastic polymers and a melt-processable composition containing the processing aid. Acrylic acid ester monomers, alkyl olefinic acid monomers, and saturated fatty acid esterified enol monomers are copolymerized to obtain a copolymer, which is then mixed with a fluorine-containing polymer to obtain a fluorine-containing processing aid, which can be used to improve the processing properties of polyolefin resins. In this patent, a processing aid is obtained by mixing a copolymer of acrylic acid ester monomers, alkyl olefinic acid monomers, and saturated fatty acid esterified enol monomers with a fluorine-containing polymer, and the fluorine-containing polymer is not environmentally friendly.

[0010] For example, the patent with publication number CN104583328A discloses a melt-processable composition having a polymer processing aid containing silicone, silicone-polyurethane and silicone-polyamide copolymers, the polysiloxane chain segments may contain long-chain alkyl, ester, ether, amide and other long-chain groups, and is used in combination with a synergist to improve the processing properties of the polymer.

[0011] For example, the patent with publication number CN1802393A discloses a melt-processable polymer composition comprising a fluorinated polymer with long chain branches, wherein the effective substance is a fluorinated polymer modified with long chain branches, and PEG and polycaprolactone are used as enhancers, which can be used to improve the processing properties of the polymer. In this patent, a fluorinated polymer is blended with PEG and polycaprolactone to obtain a processing aid, and the fluorine content is not conducive to environmental protection. Summary of the invention

[0012] Technical problems solved by the present invention:

[0013] The present invention is used to solve the problems generated during the processing of thermoplastic resins and their composite materials, reduce the adhesion between thermoplastic resins and their composite materials and metal equipment, solve the carbon deposition problem of thermoplastic resins and their composite materials on the screw and barrel, and solve the problem of dead material and stale material. The silicon-containing processing aid for thermoplastic resins provided by the present invention can improve the problems of die accumulation and melt fracture of thermoplastic resins and their composite materials during the extrusion process; can greatly improve the crystal point problem in the film production process; and further extend the screw cleaning cycle and equipment service life during the processing of thermoplastic resins and their composite materials, thereby improving production efficiency and product quality.

[0014] The technical solution adopted by the present invention is:

[0015] In view of the above technical problems, the object of the present invention is to provide a silicon-containing processing aid for thermoplastic resin and a preparation method thereof.

[0016] The silicon-containing processing aid for thermoplastic resin provided by the invention is prepared by compounding modified polysiloxane, ultrahigh molecular weight polysiloxane, filler and other additives.

[0017] (1) Utilize the polar segments and non-polar segments contained in the modified polysiloxane molecules, where the polar segments can interact with metal processing equipment and the non-polar segments can be compatible with thermoplastic resins.

[0018] (2) The modified polysiloxane molecules have a small molecular weight and are very easy to migrate between thermoplastic resin molecules. In addition, the polysiloxane chain segments have extremely low surface energy and excellent molecular flexibility. At the same time, combined with ultra-high molecular weight polysiloxane with low surface energy, the modified polysiloxane molecules and ultra-high molecular weight polysiloxane complement each other. While having excellent lubricity, they can form a dense low surface energy polysiloxane film layer on the surface of metal processing equipment, thereby reducing the adhesion of thermoplastic resins and their composite materials to metal processing equipment in the molten state.

[0019] (3) The silicon-containing processing aid for thermoplastic resin provided by the present invention can perfectly solve the problems of carbon deposition inside the barrel, material accumulation at the die, melt fracture, etc. during the processing and extrusion of thermoplastic resin, greatly prolong the screw cleaning cycle and equipment service life during the processing of thermoplastic resin and its composite materials, and improve production efficiency and product quality. When the silicon-containing processing aid for thermoplastic resin is applied to thermoplastic resin and its composite materials, it will not have an adverse effect on its mechanical properties; compared with fluorine-containing PPA, it will not cause chemical damage to organisms, which has environmental significance, and at the same time, it has economic advantages at a lower price.

[0020] The specific contents are as follows:

[0021] First, the present invention provides a silicon-containing processing aid for thermoplastic resin, wherein the components, by weight, include 5 to 85 parts of modified polysiloxane, 5 to 85 parts of ultra-high molecular weight polysiloxane, 5 to 10 parts of inorganic filler, and 1 to 5 parts of additive.

[0022] According to some preferred embodiments, the components, by weight, include 10 to 85 parts of modified polysiloxane, 10 to 85 parts of ultra-high molecular weight polysiloxane, 5 to 10 parts of inorganic filler, and 1 to 5 parts of auxiliary agent.

[0023] According to some preferred embodiments, the structural formula of the modified polysiloxane is shown in general formula (1):

[0024] (1)

[0025] R 7 , R 8 , R 18 , R 19 , R 20 , R 21 are each independently a monovalent organic group or atom;

[0026] n is an integer greater than 1;

[0027] R 7 , R 8 , R 18 , R 19 , R 20 , R 21 The structures are each independently selected from one of the general formulae (1-1) to (1-4):

[0028] (1-1)

[0029] (1-2)

[0030] (1-3)

[0031] (1-4)

[0032] a is an integer greater than 0;

[0033] b is an integer greater than 1;

[0034] R 1 The structure is selected from the general formula (1-1) or (1-2);

[0035] R 2 , R 3 , R 4 , R 5 The structures of are independently selected from the general formula (1-1) or (1-2); R 2 , R 3 , R 4 , R 5 In the structure, there is at least one A, A is as shown in the general formula (1-1) and a>8;

[0036] R 10 , R 11 , R 12 , R 13 , R 14 The structures of are independently selected from one of the general formulae (1-1) to (1-3) and (1-5):

[0037] (1-5)

[0038] R 10 , R 11 , R 12 , R 13 There is at least one B, B is as shown in general formula (1-3);

[0039] R 6 , R 9 , R 15 As shown in general formula (1-6),

[0040] (1-6)

[0041] c is an integer greater than 1;

[0042] R 16 is one of a hydrogen atom, an alkyl group, a halogenated alkyl group, and an alkyl group containing a polar group; among the alkyl group, the halogenated alkyl group, and the alkyl group containing a polar group, the number of carbon atoms is an integer of 10 to 100; the polar group containing a polar group is one of an amino group, an imide group, an alkyl group, an alkoxy group, an epoxy alkoxy group, a carboxylic acid alkoxy group, a hydroxyl group, an ester group, and a halogen atom;

[0043] R 17It is one of a hydrogen atom, an amino group, an amide group, an alkyl group, an alkoxy group, an epoxyalkoxy group, a carboxylic acid alkoxy group, a hydroxyl group, and a halogen atom; in the alkyl group, the alkoxy group, the epoxyalkoxy group, and the carboxylic acid alkoxy group, the number of carbon atoms is an integer greater than 1.

[0044] According to some preferred embodiments, the substituent R 16 In the above, the polar group is one of an amino group, an amide group, an alkoxy group, an epoxyalkoxy group, a carboxylic acid alkoxy group, a hydroxyl group, and a halogen atom.

[0045] According to some preferred embodiments, the inorganic filler includes at least one of calcium carbonate, mica powder, talc, montmorillonite, wollastonite powder, aluminum hydroxide, magnesium hydroxide, glass microbeads, kaolin, barium sulfate, titanium dioxide, silicon dioxide, and spherical silicon micropowder.

[0046] According to some preferred embodiments, the auxiliary agent includes at least one of an antioxidant, an antistatic agent, an anti-ultraviolet agent, and an antibacterial agent;

[0047] The antioxidant includes at least one of 3-(3,5-di-tert-butyl-4-hydroxyphenyl) acrylate, N-phenyl-α-naphthylamine, alkyl phenothiazine, benzotriazole, mercaptobenzothiazole, 2,6-di-tert-butyl-p-cresol, N-cyclohexyl-N'-phenyl-p-phenylenediamine, triphenyl phosphite, diphenyl-isooctyl phosphite, and tributyl phosphite;

[0048] The anti-ultraviolet agent includes at least one of phenyl o-hydroxybenzoate, 2,2',4,4'-tetrahydroxybenzophenone, and 2-(2, hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole;

[0049] The antibacterial agent includes at least one of silver ion antibacterial agent, zinc oxide, copper oxide, ammonium dihydrogen phosphate, lithium carbonate, sodium pentachlorophenol, p-nitrophenol, glutaraldehyde and ethylene glycol methyl ether.

[0050] The antistatic agent includes at least one of trimethyl ammonium chloride stearate, dimethyl amyl ammonium chloride stearate, alkyl tertiary amine sodium nitrate, trihydroxyethyl methyl quaternary ammonium sodium sulfate, N,N-hexadecylethyl morpholine sodium sulfate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, sodium polyacrylate, and sodium polystyrene sulfonate.

[0051] According to some preferred embodiments, the preparation method of the modified polysiloxane is prepared by the following steps:

[0052] Step 1: Prepare alkyl-containing cyclosiloxane, and obtain single-terminal hydrogen-containing polysiloxane through ring-opening polymerization;

[0053] Step 2: Prepare a cyclosiloxane containing a polar functional group, and obtain a single-terminal hydrogen-containing polysiloxane through ring-opening polymerization;

[0054] Step 3: Mixing the alkyl-containing single-terminal hydrogen-containing polysiloxane, the polar functional group-containing single-terminal hydrogen-containing polysiloxane and the vinyl-containing polysiloxane to obtain a modified polysiloxane through a catalytic reaction.

[0055] According to some preferred embodiments, the structure of the alkyl-containing cyclosiloxane is shown in general formula (2):

[0056] (2)

[0057] R 22 , R 23 , R 24 , R 25 , R 26 , R 27 , R 28 , R 29 are each independently a monovalent organic group or a hydrogen atom; the structure of the monovalent organic group is the general formula (1-1) or (1-2);

[0058] R 22 , R 23 , R 24 , R 25 , R 26 , R 27 , R 28 , R 29 In the structure, there is at least one A, A is as shown in the general formula (1-1) and a>8.

[0059] According to some preferred embodiments, the structure of the cyclosiloxane containing a polar functional group is shown in the general formula (3):

[0060] (3)

[0061] R 30 , R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 are each an independent monovalent organic group or a hydrogen atom; the structure of the monovalent organic group is the general formula (1-3);

[0062] R 30 , R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 In the structure, there is at least one B, and B is as shown in the general formula (1-3).

[0063] According to some preferred embodiments, in step 1 and step 2, the catalyst for the ring-opening polymerization includes one or more of sodium hydroxide, potassium hydroxide, sodium hydride, potassium hydride, tetramethylammonium hydroxide, and tetrabutylammonium hydroxide.

[0064] According to some preferred embodiments, in step 1 and step 2, the temperature range of the ring-opening polymerization is 100-200°C.

[0065] According to some preferred embodiments, in step 1 and step 2, the amount of catalyst used in the ring-opening polymerization is 0.1-2% of the total mass of the reaction material.

[0066] According to some preferred embodiments, in step 3, the weight average molecular weight of the vinyl-containing polysiloxane is in the range of 1,000-1,000,000.

[0067] According to some preferred embodiments, in step three, the catalyst is a platinum catalyst.

[0068] According to some preferred embodiments, in step three, the catalytic reaction temperature is 70-200°C.

[0069] According to some preferred embodiments, in step 3, the amount of catalyst used is 0.1-2% of the total mass of the reaction material.

[0070] According to some preferred embodiments, in step 3, the reaction molar ratio of the alkyl-containing single-terminal hydrogen-containing polysiloxane, the polar functional group-containing single-terminal hydrogen-containing polysiloxane, and the vinyl-containing polysiloxane is 10-99:10-99:1-99.

[0071] According to some preferred embodiments, the alkyl-containing cyclosiloxane has the following characteristics:

[0072] The alkyl-containing cyclosiloxane is prepared by catalytic reaction of hydrogen-containing cyclosiloxane and unsaturated alkane;

[0073] The catalyst for preparing the alkyl-containing cyclosiloxane is a platinum catalyst;

[0074] The preparation temperature of alkyl-containing cyclosiloxane is 70 ~ 200 °C;

[0075] The amount of catalyst used in the preparation of alkyl-containing cyclosiloxane is 0.1-2% of the total mass of the reaction material;

[0076] The molar ratio of hydrogen-containing cyclosiloxane to unsaturated alkane is 1:1 to 4;

[0077] The hydrogen-containing cyclosiloxane may be tetramethylcyclotetrasiloxane;

[0078] Unsaturated alkanes are alkenes having unsaturated double bonds.

[0079] According to some preferred embodiments, the cyclosiloxane containing polar functional groups has the following characteristics:

[0080] The structure of the cyclosiloxane containing polar functional groups is shown in the general formula (3):

[0081] (3)

[0082] R 30 , R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 are each an independent monovalent organic group or a hydrogen atom; the structure of the monovalent organic group is the general formula (1-3);

[0083] R 30 , R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 In the structure, there is at least one B, and B is as shown in the general formula (1-3);

[0084] The polar functional group-containing cyclosiloxane is prepared by catalytic reaction of vinyl-containing cyclosiloxane and polar functional group-containing alkane;

[0085] The catalyst for preparing the cyclosiloxane containing polar functional groups is one of sodium ethoxide, sodium hydride, tetramethylammonium hydroxide and tetrabutylammonium hydroxide;

[0086] The preparation temperature of cyclosiloxane containing polar functional groups is 90~150℃;

[0087] The amount of catalyst used in the preparation of cyclosiloxane containing polar functional groups is 0.1-2% of the total mass of the reaction material;

[0088] The catalyst for preparing the cyclosiloxane containing polar functional groups is diluted with a diluent before use, and the diluent includes at least one of methanol, ethanol, isopropanol, and cyclohexane;

[0089] The molar ratio of vinyl cyclosiloxane to polar functional group-containing alkane is 1:1-4;

[0090] The vinyl-containing cyclosiloxane includes at least one of tetramethyltetravinylcyclotetrasiloxane, octavinylcyclotetrasiloxane, hexavinylcyclotrisiloxane, trimethyltrivinylcyclotrisiloxane, hexamethyldivinylcyclotetrasiloxane, tetraphenyltetravinylcyclotetrasiloxane, diphenylhexavinylcyclotetrasiloxane and triphenyltrivinylcyclotrisiloxane;

[0091] The structural formula of alkanes containing polar functional groups is shown in the general formula (1-7):

[0092] (1-7)

[0093] X is a hydrogen atom, a halogen atom, or any one of the general formula (1-1) and the general formula (1-2).

[0094] According to some preferred embodiments, the ultra-high molecular weight polysiloxane has the following characteristics:

[0095] The structure of ultra-high molecular weight polysiloxane is shown in the general formula (4):

[0096] (4)

[0097] R1 and R2 are each independently a monovalent organic group or atom; x is an integer greater than 1000;

[0098] R1 and R2 are one or more of methyl, ethyl, phenyl, hydroxyl, vinyl, hydrogen atom, and long-chain alkyl with carbon number greater than 8; the long-chain alkyl can be any straight-chain alkyl or branched-chain alkyl.

[0099] Second, the present invention provides a method for preparing the aforementioned silicon-containing processing aid for thermoplastic resin, comprising the following steps:

[0100] S1 modified polysiloxane, ultra-high molecular weight polysiloxane, inorganic filler and additives are blended in a solvent at high temperature to obtain a mixed material;

[0101] The S2 mixed material is spray granulated to obtain a silicon-containing processing aid for thermoplastic resin.

[0102] According to some preferred embodiments, the solvent includes at least one of benzene, toluene, xylene, acetone, cyclohexanone, and butanone.

[0103] The beneficial effects achieved by the present invention are:

[0104] The silicon-containing processing aid for thermoplastic resin used in the present invention has:

[0105] (1) When used in thermoplastic resins and their composite materials, it can significantly improve the processing and extrusion properties of thermoplastic resins and their composite materials;

[0106] (2) Silicon-containing processing aids for thermoplastic resins are prepared by compounding modified polysiloxane, ultra-high molecular weight polysiloxane, fillers and other additives. The raw materials are easily available, the preparation process is simple and the price is low.

[0107] (3) Polysiloxane molecules and ultra-high molecular weight polysiloxane complement each other. While having excellent lubricity, they can form a dense low-surface-energy polysiloxane film on the surface of metal processing equipment, reducing the adhesion of thermoplastic resins and their composite materials to metal processing equipment in a molten state. This can perfectly solve the problems of carbon deposition inside the barrel, die accumulation, and melt fracture during the processing and extrusion of thermoplastic resins.

[0108] (4) Extend the screw cleaning cycle and equipment service life during the processing of thermoplastic resins and their composite materials, and improve production efficiency and product quality;

[0109] (5) When the silicon-containing processing aid for thermoplastic resin is used in thermoplastic resin and its composite materials, it will not have an adverse effect on their mechanical properties;

[0110] (6) Compared with fluorinated PPA, it does not cause chemical damage to organisms and has environmental significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0111] Figure 1-Figure 9 The results of melt fracture of different samples after 6 hours ( Figure 1 For the blank group, Figure 2 For Example 1, Figure 3 For Example 2, Figure 4 For Example 3, Figure 5 For Example 4, Figure 6 For Example 5, Figure 7 For Example 6, Figure 8 For comparative example 1, Fig. 9 For comparative example 2). DETAILED DESCRIPTION

[0112] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0113] Example 1

[0114] This embodiment provides a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. The components of the silicon-containing processing aid are as follows:

[0115] Modified polysiloxane 1: 22.5 parts

[0116] Ultra-high molecular weight polysiloxane: 22.5 parts

[0117] Talc: 4 parts

[0118] Benzotriazole: 0.5 parts

[0119] Ammonium dihydrogen phosphate: 0.5 parts

[0120] Toluene: 50 parts

[0121] Modified polysiloxane, ultra-high molecular weight polysiloxane, talcum powder, benzotriazole, ammonium dihydrogen phosphate and toluene are added into a reaction kettle in proportion, melt-mixed evenly, and then spray-granulated to obtain a silicon-containing processing aid 1 for thermoplastic resin.

[0122] Among them, the modified polysiloxane 1 has the following structure:

[0123]

[0124] The preparation method of modified polysiloxane 1 is as follows:

[0125] Step 1: α-dodecene and tetramethylcyclotetrasiloxane are added to a flask at a molar ratio of 4:1, respectively, and stirred at 60°C for 1 hour. After stirring evenly, 0.1% of the total weight of α-dodecene and tetramethylcyclotetrasiloxane is slowly dripped into a chloroplatinic acid catalyst, and the reaction is continued for 8 hours under stirring. After the reaction is completed, the temperature is increased to 150°C, and 0.2% of the total weight of α-dodecene and tetramethylcyclotetrasiloxane is added with tetramethylammonium hydroxide. After stirring and mixing for 1 hour, heptamethyltrisiloxane is added, and the reaction is continued for 8 hours under stirring. After the reaction is completed, the temperature is increased to 180°C and the pressure is reduced to remove low (remove low boiling points) for 2 hours to obtain an alkyl-modified single-terminal hydrogen-containing polysiloxane A1 with 16 polymer segments.

[0126] Step 2: Add butyl acetate and tetramethyltetravinylcyclotetrasiloxane in a molar ratio of 4:1 to a flask, stir at 85°C for 1h, and then slowly drop a 20wt% tetramethylammonium hydroxide ethanol solution (0.5% of the total mass of butyl acetate and tetramethyltetravinylcyclotetrasiloxane) into the flask, stir evenly at 85°C, heat to 150°C, stir for 18h, then add monohydrogenated double-capped siloxane, continue stirring for 8h, and after the reaction is complete, increase the temperature to 180°C and decompress for 2h to obtain a polar group-modified single-terminal hydrogenated polysiloxane B1 having 16 polymer segments;

[0127] Step 3: Add A1, B1 and vinyl polysiloxane with a polymer chain length of 40 in a molar ratio of 1:1:1 into a flask and stir at 85°C for 1 hour. After stirring evenly, slowly drop 0.1% of the total mass of A1, B1 and vinyl polysiloxane into a chloroplatinic acid catalyst, and continue stirring the reaction for 8 hours to obtain the modified polysiloxane additive 1.

[0128] Among them, ultra-high molecular weight polysiloxane (Hesheng Silicon Industry Co., Ltd., methyl silicone rubber with a molecular weight of 740,000) has the following structure:

[0129] .

[0130] Example 2

[0131] This embodiment provides a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. The components of the silicon-containing processing aid are as follows:

[0132] Modified polysiloxane 1:15 parts

[0133] Ultra-high molecular weight polysiloxane: 30 parts

[0134] Talc: 4 parts

[0135] Benzotriazole: 0.5 parts

[0136] Ammonium dihydrogen phosphate: 0.5 parts

[0137] Toluene: 50 parts

[0138] Modified polysiloxane, ultra-high molecular weight polysiloxane, talc, benzotriazole, ammonium dihydrogen phosphate and toluene are added into a reaction kettle in proportion, melt-mixed evenly, and then spray-granulated to obtain a silicon-containing processing aid 2 for thermoplastic resin.

[0139] The structure and preparation method of modified polysiloxane 1 are the same as those in Example 1.

[0140] The structure of the ultra-high molecular weight polysiloxane is the same as that in Example 1.

[0141] Example 3

[0142] This embodiment provides a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. The components of the silicon-containing processing aid are as follows:

[0143] Modified polysiloxane 1:30 parts

[0144] Ultra-high molecular weight polysiloxane: 15 parts

[0145] Talc: 4 parts

[0146] Benzotriazole: 0.5 parts

[0147] Ammonium dihydrogen phosphate: 0.5 parts

[0148] Toluene: 50 parts

[0149] Modified polysiloxane, ultra-high molecular weight polysiloxane, talcum powder, benzotriazole, ammonium dihydrogen phosphate and toluene are added into a reaction kettle in proportion, melt-mixed evenly, and then spray-granulated to obtain a silicon-containing processing aid 3 for thermoplastic resin.

[0150] The structure and preparation method of modified polysiloxane 1 are the same as those in Example 1.

[0151] The structure of the ultra-high molecular weight polysiloxane is the same as that in Example 1.

[0152] Example 4

[0153] This embodiment provides a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. The components of the silicon-containing processing aid are as follows:

[0154] Modified polysiloxane 2: 22.5 parts

[0155] Ultra-high molecular weight polysiloxane: 22.5 parts

[0156] Talc: 4 parts

[0157] Benzotriazole: 0.5 parts

[0158] Ammonium dihydrogen phosphate: 0.5 parts

[0159] Toluene: 50 parts

[0160] Modified polysiloxane, ultra-high molecular weight polysiloxane, talcum powder, benzotriazole, ammonium dihydrogen phosphate and toluene are added into a reaction kettle in proportion, melt-mixed evenly, and then spray-granulated to obtain a silicon-containing processing aid 4 for thermoplastic resin.

[0161] The modified polysiloxane 2 has the following structure:

[0162] .

[0163] The preparation method of modified polysiloxane 2 is as follows:

[0164] Step 1: α-dodecene and tetramethylcyclotetrasiloxane are added to a flask at a molar ratio of 4:1, respectively, and stirred at 60°C for 1 hour. After stirring evenly, 0.1% of the total weight of α-dodecene and tetramethylcyclotetrasiloxane is slowly dripped into a chloroplatinic acid catalyst, and the reaction is continued for 8 hours under stirring; after the reaction is completed, the temperature is increased to 150°C, 0.2% of the total weight of α-dodecene and tetramethylcyclotetrasiloxane is added with tetramethylammonium hydroxide, and the mixture is stirred for 1 hour, and then the monohydrogenated double-capped siloxane is added, and the reaction is continued for 8 hours under stirring. After the reaction is completed, the temperature is increased to 180°C and the pressure is reduced for 2 hours to obtain an alkyl-modified single-terminal hydrogenated polysiloxane A1 with 16 polymer segments;

[0165] Step 2: Add butyl acetate and tetramethyltetravinylcyclotetrasiloxane in a molar ratio of 4:1 to a flask, stir at 85°C for 1h, and then slowly drop a 20wt% tetramethylammonium hydroxide ethanol solution (0.5% of the total mass of butyl acetate and tetramethyltetravinylcyclotetrasiloxane) into the flask, stir evenly at 85°C, heat to 150°C, stir for 18h, then add monohydrogenated double-capped siloxane, continue stirring for 8h, and after the reaction is complete, increase the temperature to 180°C and decompress for 2h to obtain a polar group-modified single-terminal hydrogenated polysiloxane B1 having 16 polymer segments;

[0166] Step 3: Add A1, B1 and vinyl polysiloxane with a polymer chain length of 80 in a molar ratio of 1:1:1 into a flask and stir at 85°C for 1 hour. After stirring evenly, slowly drop 0.1% of the total mass of A1, B1 and vinyl polysiloxane into a chloroplatinic acid catalyst, and continue stirring the reaction for 8 hours to obtain the modified polysiloxane additive 2.

[0167] The structure of the ultra-high molecular weight polysiloxane is the same as that in Example 1.

[0168] Example 5

[0169] This embodiment provides a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. The components of the silicon-containing processing aid are as follows:

[0170] Modified polysiloxane 2: 15 parts

[0171] Ultra-high molecular weight polysiloxane: 30 parts

[0172] Talc: 4 parts

[0173] Benzotriazole: 0.5 parts

[0174] Ammonium dihydrogen phosphate: 0.5 parts

[0175] Toluene: 50 parts

[0176] Modified polysiloxane, ultra-high molecular weight polysiloxane, talcum powder, benzotriazole, ammonium dihydrogen phosphate and toluene are added into a reaction kettle in proportion, melt-mixed evenly, and then spray-granulated to obtain a silicon-containing processing aid 5 for thermoplastic resin.

[0177] The structure and preparation method of modified polysiloxane 2 are the same as those in Example 4.

[0178] The structure of the ultra-high molecular weight polysiloxane is the same as that in Example 1.

[0179] Example 6

[0180] This embodiment provides a silicon-containing processing aid for thermoplastic resin and a preparation method thereof. The components of the silicon-containing processing aid are as follows:

[0181] Modified polysiloxane 2: 30 parts

[0182] Ultra-high molecular weight polysiloxane: 15 parts

[0183] Talc: 4 parts

[0184] Benzotriazole: 0.5 parts

[0185] Ammonium dihydrogen phosphate: 0.5 parts

[0186] Toluene: 50 parts

[0187] Modified polysiloxane, ultra-high molecular weight polysiloxane, talcum powder, benzotriazole, ammonium dihydrogen phosphate and toluene are added into a reaction kettle in proportion, melt-mixed evenly, and then spray-granulated to obtain a silicon-containing processing aid 6 for thermoplastic resin.

[0188] The structure and preparation method of modified polysiloxane 2 are the same as those in Example 4.

[0189] The structure of the ultra-high molecular weight polysiloxane is the same as that in Example 1.

[0190] Comparative Example 1

[0191] A silicon-containing processing aid for removing modified polysiloxane to prepare thermoplastic resin, the components of the processing aid are as follows:

[0192] Ultra-high molecular weight polysiloxane: 90 parts

[0193] Talc: 8 parts

[0194] Benzotriazole: 1 part

[0195] Ammonium dihydrogen phosphate: 1 part

[0196] Ultra-high molecular weight polysiloxane, talc, benzotriazole and ammonium dihydrogen phosphate are uniformly mixed to obtain a silicon-containing processing aid 7 for thermoplastic resin.

[0197] The structure of the ultra-high molecular weight polysiloxane is the same as that in Example 1.

[0198] Comparative Example 2

[0199] A processing aid for thermoplastic resin is prepared by replacing modified polysiloxane and ultra-high molecular weight polysiloxane with commercially available fluorinated PPA. The components of the processing aid are as follows:

[0200] Fluorinated PPA: 90 parts

[0201] Talc: 8 parts

[0202] Benzotriazole: 1 part

[0203] Ammonium dihydrogen phosphate: 1 part

[0204] The processing aid 8 for thermoplastic resin is prepared by uniformly mixing fluorine-containing PPA, talc, benzotriazole and ammonium dihydrogen phosphate.

[0205] Test example

[0206] The silicon-containing processing aids 1-6 for thermoplastic resin prepared in Examples 1-6 and the processing aids 7-8 for thermoplastic resin prepared in Comparative Examples 1-2 were used as test samples for testing.

[0207] Experiment on improving the processing properties of linear low density polyethylene (LLDPE)

[0208] Table 1 Material ratio for improving LLDPE processing performance

[0209]

[0210] 2. The test results of LLDPE processing performance are shown in Table 2 and Figure 1-9 shown.

[0211] Note: The extrusion effect test of the high-pressure capillary extruder was conducted at 180°C and 120 rpm. The changes in the film accumulation, melt fracture and torque after 6 hours were tested. The results of the melt fracture test are shown in the figure below. Figure 1-9 As shown, Figure 1 The blank group (no auxiliary materials added) Figure 2-7 Examples 1-6 and 8-9 are comparative examples 1-2.

[0212] Table 2 Test results of LLDPE processing properties

[0213]

[0214] In summary, the silicon-containing composition provided by the present invention can be applied to LLDPE materials to significantly improve the processing performance of LLDPE materials, eliminate melt fracture, improve die buildup, and reduce torque during processing.

[0215] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A silicon-containing processing aid for thermoplastic resin, characterized in that: The raw material components include modified polysiloxane, ultra-high molecular weight polysiloxane, inorganic filler and additives; The inorganic filler includes at least one of calcium carbonate, mica powder, talc powder, montmorillonite, wollastonite powder, aluminum hydroxide, magnesium hydroxide, glass microspheres, kaolin, barium sulfate, titanium dioxide, silicon dioxide, and spherical silicon micropowder; The auxiliary agent includes at least one of an antioxidant, an antistatic agent, an anti-ultraviolet agent, and an antibacterial agent; The structural formula of the modified polysiloxane is shown in the general formula (1): （1） R 7 , R 8 , R 18 , R 19 , R 20 , R 21 are each independently a monovalent organic group or atom; n is an integer greater than 1; R 20 , R 21 The structures are each independently selected from one of the general formulae (1-1) to (1-4): （1-1） （1-2） （1-3） （1-4） R 7 , R 8 The structures of are each independently selected from one of the general formulae (1-1) to (1-3); R 18 , R 19 The structure is shown in the general formula (1-4); a is an integer greater than 0; b is an integer greater than 1; R 1 The structure is selected from the general formula (1-1) or (1-2); R 2 , R 3 , R 4 , R 5 The structures of are independently selected from the general formula (1-1) or (1-2); R 2 , R 3 , R 4 , R 5 In the structure, there is at least one A, A is as shown in the general formula (1-1) and a>8; R 10 , R 11 , R 12 , R 13 , R 14 The structures of are independently selected from one of the general formulae (1-1) to (1-3) and (1-5): （1-5） R 10 , R 11 , R 12 , R 13 There is at least one B, B is as shown in general formula (1-3); R 6 , R 9 , R 15 As shown in general formula (1-6), （1-6） c is an integer greater than 1; R 16 is one of a hydrogen atom, an alkyl group, a halogenated alkyl group, and an alkyl group containing a polar group; in the alkyl group, the halogenated alkyl group, and the alkyl group containing a polar group, the number of carbon atoms is an integer of 10 to 100; R 17 is one of a hydrogen atom, an amino group, an amide group, an alkyl group, an alkoxy group, an epoxyalkoxy group, a carboxylic acid alkoxy group, a hydroxyl group, and a halogen atom; in the alkyl group, the alkoxy group, the epoxyalkoxy group, and the carboxylic acid alkoxy group, the number of carbon atoms is an integer greater than 1; The preparation method of modified polysiloxane comprises the following steps: Step 1: Prepare an alkyl-containing cyclosiloxane, and obtain an alkyl-containing single-terminal hydrogen-containing polysiloxane through ring-opening polymerization; the preparation method of the alkyl-containing cyclosiloxane is: prepare the alkyl-containing cyclosiloxane through catalytic reaction of hydrogen-containing cyclosiloxane and unsaturated alkane; the molar ratio of hydrogen-containing cyclosiloxane to unsaturated alkane is 1:1~4; Step 2: Prepare a cyclosiloxane containing a polar functional group, and obtain a single-terminal hydrogen-containing polysiloxane containing a polar functional group through ring-opening polymerization; the preparation method of the cyclosiloxane containing a polar functional group is to obtain it by catalytic reaction of a vinyl cyclosiloxane and an alkane containing a polar functional group; the molar ratio of the vinyl cyclosiloxane to the alkane containing a polar functional group is 1:1~4; Step 3: Mixing an alkyl-containing single-ended hydrogen-containing polysiloxane, a polar functional group-containing single-ended hydrogen-containing polysiloxane, and a vinyl-containing polysiloxane, and subjecting the mixture to a catalytic reaction to obtain a modified polysiloxane; the reaction molar ratio of the alkyl-containing single-ended hydrogen-containing polysiloxane, the polar functional group-containing single-ended hydrogen-containing polysiloxane, and the vinyl-containing polysiloxane is 10-99:10-99:1-99; and the weight average molecular weight of the vinyl-containing polysiloxane is in the range of 1000-1000000; The structure of ultra-high molecular weight polysiloxane is shown in the general formula (4): （4） R1 and R2 are each independently a monovalent organic group or atom; x is an integer greater than 1000; R1 and R2 are one or more of methyl, ethyl, phenyl, hydroxyl, vinyl, hydrogen atom, and long-chain alkyl with carbon number greater than 8; the long-chain alkyl is a straight-chain alkyl or a branched-chain alkyl.

2. The silicon-containing processing aid for thermoplastic resin according to claim 1, characterized in that: Each component of the raw material includes at least one of characteristics (I-1) to characteristics (I-5): (I-1) The raw material components, by weight, include 10 to 85 parts of modified polysiloxane, 10 to 85 parts of ultra-high molecular weight polysiloxane, 5 to 10 parts of inorganic filler, and 1 to 5 parts of auxiliary agent; (I-2) The antioxidant includes at least one of 3-(3,5-di-tert-butyl-4-hydroxyphenyl) acrylate, N-phenyl-α-naphthylamine, alkyl phenothiazine, benzotriazole, mercaptobenzothiazole, 2,6-di-tert-butyl-p-cresol, N-cyclohexyl-N'-phenyl-p-phenylenediamine, triphenyl phosphite, diphenyl-isooctyl phosphite, and tributyl phosphite; (I-3) The anti-ultraviolet agent includes at least one of o-hydroxybenzoic acid phenyl ester, 2,2',4,4'-tetrahydroxybenzophenone, and 2-(2, hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole; (I-4) The antibacterial agent includes at least one of silver ion antibacterial agent, zinc oxide, copper oxide, ammonium dihydrogen phosphate, lithium carbonate, sodium pentachlorophenol, p-nitrophenol, glutaraldehyde, and ethylene glycol methyl ether; (I-5) The antistatic agent includes at least one of trimethyl ammonium chloride stearate, dimethyl amyl ammonium chloride stearate, alkyl tertiary amine sodium nitrate, trihydroxyethyl methyl quaternary ammonium sodium sulfate, N,N-hexadecylethyl morpholine sodium sulfate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, sodium polyacrylate, and sodium polystyrene sulfonate.

3. The silicon-containing processing aid for thermoplastic resin according to claim 1, characterized in that R 16 In the above, the polar group is one of an amino group, an amide group, an alkoxy group, an epoxyalkoxy group, a carboxylic acid alkoxy group, a hydroxyl group, and a halogen atom.

4. The silicon-containing processing aid for thermoplastic resin according to claim 1, characterized in that The alkyl-containing cyclosiloxane includes at least one of the characteristics (II-1) to (II-4): (II-1) The structural formula of the alkyl-containing cyclosiloxane is shown in the general formula (2): （2） R 22 , R 23 , R 24 , R 25 , R 26 , R 27 , R 28 , R 29 are each independently a monovalent organic group or a hydrogen atom; the structure of the monovalent organic group is the general formula (1-1) or (1-2); R 22 , R 23 , R 24 , R 25 , R 26 , R 27 , R 28 , R 29 In the structure, there is at least one A, A is as shown in the general formula (1-1) and a>8; (II-2) The catalyst used in the catalytic reaction is a platinum catalyst; the reaction temperature is 70-200°C; the amount of the catalyst used accounts for 0.1-2% of the total mass of the reaction material; (II-3) the hydrogen-containing cyclosiloxane is tetramethylcyclosiloxane; (II-4) Unsaturated alkanes are olefins containing an unsaturated double bond.

5. The silicon-containing processing aid for thermoplastic resin according to claim 1, characterized in that: The polar functional group-containing cyclosiloxane comprises at least one of the characteristics (III-1) to (III-4): (III-1) The structure of the cyclosiloxane containing a polar functional group is shown in the general formula (3): （3） R 30 , R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 are each an independent monovalent organic group or a hydrogen atom; the structure of the monovalent organic group is the general formula (1-3); R 30 , R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 In the structure, there is at least one B, and B is as shown in the general formula (1-3); (III-2) The catalyst used in the catalytic reaction includes at least one of sodium ethoxide, sodium hydride, tetramethylammonium hydroxide, and tetrabutylammonium hydroxide; the reaction temperature is 90-150°C; the amount of the catalyst used accounts for 0.1-2% of the total mass of the reaction material; the catalyst is used after dilution, and the diluent includes at least one of methanol, ethanol, isopropanol, and cyclohexane; (III-3) vinyl-containing cyclosiloxanes including at least one of tetramethyltetravinylcyclotetrasiloxane, octavinylcyclotetrasiloxane, hexavinylcyclotrisiloxane, trimethyltrivinylcyclotrisiloxane, hexamethyldivinylcyclotetrasiloxane, tetraphenyltetravinylcyclotetrasiloxane, diphenylhexavinylcyclotetrasiloxane and triphenyltrivinylcyclotrisiloxane; (III-4) The structural formula of the alkane containing polar functional groups is shown in the general formula (1-7): （1-7） X is a hydrogen atom, a halogen atom, or any one of the general formula (1-1) and the general formula (1-2).

6. The silicon-containing processing aid for thermoplastic resin according to claim 1, characterized in that: The method for preparing the modified polysiloxane comprises at least one of the features (IV-1) to (IV-6): (IV-1) In step 1 and step 2, the catalyst for ring-opening polymerization includes at least one of sodium hydroxide, potassium hydroxide, sodium hydride, potassium hydride, tetramethylammonium hydroxide, and tetrabutylammonium hydroxide; (IV-2) In step 1 and step 2, the amount of the catalyst used for the ring-opening polymerization is 0.1-2% of the total mass of the reaction material; (IV-3) In step 1 and step 2, the temperature range of the ring-opening polymerization is 100 to 200°C; (IV-4) In step 3, the catalyst is a platinum catalyst; (IV-5) In step 3, the catalytic reaction temperature is 70 to 200°C; (IV-6) In step 3, the amount of catalyst used accounts for 0.1~2% of the total mass of the reaction material.

7. A method for preparing a silicon-containing processing aid for thermoplastic resin according to any one of claims 1 to 6, characterized in that: The steps include: Step 1: Blending modified polysiloxane, ultra-high molecular weight polysiloxane, inorganic filler and additive in a solvent to obtain a mixed material; Step 2: The mixed material is spray-granulated to obtain a silicon-containing processing aid for thermoplastic resin.

Images