Easy-to-clean scratch-resistant polypropylene material and preparation method thereof

Abstract

The invention discloses an easy-to-clean scratch-resistant polypropylene material and a preparation method thereof. The easy-to-clean scratch-resistant polypropylene material is prepared by using the following raw materials in parts by weight: 100 parts of polypropylene resin, 1 to 5 parts of unsaturated carboxylic acid, 0.2 to 0.5 parts of initiator, 1 to 2 parts of dispersing solvent, 0.1 to 0.3 parts of antioxidant 1#, 0.05 to 0.3 parts of catalyst, 0.3 to 1.2 parts of antioxidant 2#, 0.5 to 2.5 parts of lubricant, and 0.8X to 1.0X parts of perfluoroalkyl alcohol, wherein X=(m1 / M1×M2)×N; m1 is the added mass of the unsaturated carboxylic acid, M1 is the molecular weight of the unsaturated carboxylic acid, M2 is the molecular weight of the perfluoroalkyl alcohol, and N is the number of carboxylic acids in the unsaturated carboxylic acid.

Description

Technical Field

[0001] The invention relates to the field of polymer technology, and in particular to an easy-to-clean scratch-resistant polypropylene material and a preparation method thereof. Background Art

[0002] Polypropylene material has the advantages of being non-toxic, low odor, low price, chemical corrosion resistance, good mechanical properties, and easy molding and processing. As one of the five general-purpose plastics, it is widely used in chemical fiber, construction, light industry, automobiles, home appliances, packaging materials and other fields. With the development of technology, the application scope of polypropylene materials is constantly expanding. However, in actual application, polypropylene materials also face many challenges. When polypropylene materials are used as kitchen appliance parts, since kitchen appliances are in the kitchen environment for a long time, they will inevitably come into contact with water or oil and stick to the surface of the material, making the surface difficult to clean and causing serious surface stains. At the same time, polypropylene materials are relatively soft, with low surface hardness and easy to be scratched, which greatly reduces the consumer experience during use.

[0003] The invention has good application prospects and a broad market for improving the easy-cleaning and scratch-resistant properties of polypropylene materials. At present, the easy-cleaning and scratch-resistant properties of polypropylene materials are improved by adding organic siloxane or fluorine-containing additives by a blending method. For example, patent CN107163389A discloses a highly hydrophobic and scratch-resistant polypropylene material, which is obtained by blending fluorine-containing additives, silicone masterbatch and PP; patent CN112940391A discloses a method for preparing oil-resistant polypropylene plastic, which uses organic silicone resin and PP to reduce the surface tension of polypropylene-based composite materials to achieve the purpose of oil resistance; patent CN110819008A discloses an easy-to-clean spray-free polypropylene material and a preparation method thereof, and believes that the fluorine-containing additives are all directly added, and the method of preparing the masterbatch and then adding is not adopted. The method of adding the masterbatch can effectively improve the dispersion of the additives and better play the role of the additives. An easy-to-clean-metallic color powder is used to obtain an easy-to-clean spray-free polypropylene material and a preparation method thereof. Summary of the invention

[0004] The purpose of the present invention is to provide an easy-to-clean and scratch-resistant polypropylene material and a preparation method thereof, and to provide a new idea for improving the easy-to-clean and scratch-resistant properties of polypropylene materials, so as to overcome the defects of the prior art. The present invention discloses a scheme for improving the easy-to-clean and scratch-resistant properties of polypropylene materials, wherein perfluoroalkyl alcohol is introduced into the polypropylene molecular chain by a melt chemical grafting method, the surface energy of the material is reduced, the surface of the material has hydrophobic and oleophobic properties, and the easy-to-clean and scratch-resistant properties of the surface of the polypropylene material parts are improved.

[0005] The technical solution of the present invention is as follows:

[0006] An easy-to-clean scratch-resistant polypropylene material, wherein the easy-to-clean scratch-resistant polypropylene material is prepared from the following raw materials in parts by weight:

[0007] Polypropylene grafted unsaturated carboxylic acid 100 parts

[0008] Catalyst 0.05~3 parts

[0009] Antioxidant 2# 0.3~1.2 parts

[0010] Lubricant 0.5~2.5 parts

[0011] 0.8X to 1.0X parts of perfluoroalkyl alcohol;

[0012] Wherein, X=(m1 / M1×M2)×N; m1 is the added mass of the unsaturated carboxylic acid, M1 is the molecular weight of the unsaturated carboxylic acid, M2 is the molecular weight of the perfluoroalkyl alcohol, and N is the number of carboxylic acid functional groups of the unsaturated carboxylic acid.

[0013] The polypropylene grafted unsaturated carboxylic acid is prepared from the following raw materials in parts by weight:

[0014] Polypropylene resin 100 parts

[0015] Unsaturated carboxylic acid 1-5 parts

[0016] Initiator 0.2~0.5 parts

[0017] Dispersing solvent 1-2 parts

[0018] Antioxidant 1# 0.1-0.3 parts.

[0019] The preparation method of polypropylene grafted unsaturated carboxylic acid comprises the following steps:

[0020] Unsaturated carboxylic acid, initiator and antioxidant 1# are added to the dispersion solvent and stirred to prepare a mixed solution. The mixed solution is mixed with polypropylene resin particles and then added to a twin-screw extruder for mixing, melting, extruding and granulation to obtain polypropylene grafted unsaturated carboxylic acid.

[0021] The polypropylene resin comprises the following components in parts by weight:

[0022] High viscosity polypropylene resin 70-100 parts

[0023] Low viscosity polypropylene resin 0-30 parts

[0024] The high viscosity polypropylene resin has a melt index of 2 to 10 g / 10 min when tested at 230° C.×2.16 kg.

[0025] The low viscosity polypropylene resin has a melt index of 30 to 100 g / 10 min when tested under the conditions of 230° C.×2.16 kg. The unsaturated carboxylic acid includes at least one of acrylic acid, crotonic acid, itaconic acid and maleic anhydride.

[0026] The initiator includes at least one of diisopropylbenzene peroxide, tert-butyl peroxybenzoate, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, and di-tert-butyl diisopropylbenzene peroxide;

[0027] The dispersing solvent includes soybean oil and / or dimethyl silicone oil;

[0028] The antioxidant 1# is antioxidant 5057 or antioxidant 1135.

[0029] The catalyst is one of zinc oxide, tin oxide and antimony trioxide.

[0030] The antioxidant 2# is one or two of antioxidant 1010, antioxidant 168, and antioxidant 1076; and the lubricant is silicone masterbatch.

[0031] The perfluoroalkyl alcohol is at least one of 2-perfluorooctylethanol, 2-(perfluorodecyl)ethanol, perfluorodecanol and perfluorobutanol.

[0032] The method for preparing the easy-to-clean scratch-resistant polypropylene material comprises the following steps:

[0033] The polypropylene grafted unsaturated carboxylic acid is mixed evenly with perfluoroalkyl alcohol, catalyst, antioxidant 2# and lubricant, added into a twin-screw extruder for mixing, melting, extruding and reacting, and granulating to obtain the easy-to-clean scratch-resistant polypropylene material.

[0034] The unsaturated carboxylic acid comprises at least one of acrylic acid, crotonic acid, itaconic acid and maleic anhydride, preferably an unsaturated carboxylic acid having 2 carboxylic acids;

[0035] As an embodiment of the present invention, the method for preparing the easy-to-clean, scratch-resistant, spray-free polypropylene material comprises the following steps:

[0036] (1) adding unsaturated carboxylic acid, initiator and antioxidant into a dispersing solvent, wherein the antioxidant in this step is preferably a liquid antioxidant 5057 or an antioxidant 1135, and mixing the mixed liquid with polyolefin resin particles by low-speed mechanical stirring, adding the mixed liquid into a twin-screw extruder for mixing, melting and extruding reaction, and then stranding, pelletizing and drying to obtain a polypropylene grafted unsaturated carboxylic acid raw material;

[0037] (2) The polypropylene grafted unsaturated carboxylic acid raw material prepared in step (1) is uniformly mixed with the perfluoroalkyl alcohol, catalyst, antioxidant and lubricant by a low-speed mechanical mixing, and then mixed and melted and extruded by a twin-screw extruder for reaction, and then pelletized and dried to obtain the easy-to-clean scratch-resistant polypropylene material.

[0038] Compared with the prior art, the beneficial effects are:

[0039] The present invention adopts a chemical grafting method to introduce a fluorine auxiliary agent with low surface energy and the characteristics of easy cleaning and scratch resistance into a polypropylene molecular chain through melt chemical grafting, so as to achieve molecular-level dispersion, greatly improve the use efficiency of the fluorine auxiliary agent in terms of easy cleaning and scratch resistance, and at the same time, because the fluorine auxiliary agent is combined with polypropylene through chemical bonds, it is not easy to precipitate, thereby improving the easy cleaning and scratch resistance of the surface of a polypropylene material part; compared with traditional melt blending, the fluorine auxiliary agent and the base material are only physically dispersed, and when the added amount is small, the ideal effect cannot be achieved, and when the added amount is large, it is easy to precipitate and has the defects of the like. The present invention grafts the fluorine auxiliary agent onto the polypropylene molecular chain through chemical bonds, thereby obtaining a highly efficient, easy-to-clean and scratch-resistant polypropylene material. DETAILED DESCRIPTION

[0040] The present invention is described in detail below in conjunction with embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, some adjustments and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0041] Example 1

[0042] 1. Step (1): Preparation of polypropylene grafted with unsaturated carboxylic acid

[0043] Parts by weight:

[0044] Polypropylene resin 100 parts

[0045] Unsaturated carboxylic acid 1 part

[0046] Initiator 0.2 parts

[0047] Dispersing solvent 1 part

[0048] Antioxidant 1# 0.1 part

[0049] Unsaturated carboxylic acid, initiator and antioxidant 1# are added to the dispersion solvent, the mixture is uniformly mixed with polypropylene resin by low-speed mechanical stirring, and then added to a twin screw, and the extrusion zone 1 to zone 5 are 160°C, 180°C, 190°C, 200°C, 210°C in sequence, the screw speed is 400rpm, melt mixing, graft copolymerization, strand cutting, pelletizing and drying are performed to obtain a polypropylene grafted unsaturated carboxylic acid raw material;

[0050] The polypropylene resin is 100 parts of high-viscosity polypropylene resin, and its melt index is 2g / 10min;

[0051] The unsaturated carboxylic acid is acrylic acid;

[0052] The initiator is dicumyl peroxide;

[0053] The dispersing solvent is soybean oil;

[0054] The antioxidant 1# is antioxidant 5057;

[0055] 2. Step (2): Preparation of easy-to-clean scratch-resistant polypropylene material

[0056] 100 parts of polypropylene grafted unsaturated carboxylic acid raw material

[0057] Catalyst 0.05 parts

[0058] Antioxidant 2# 0.3 parts

[0059] 0.5 parts of lubricant

[0060] 4.0 parts of perfluoroalkyl alcohol

[0061] The polypropylene grafted unsaturated carboxylic acid raw material is prepared in step (1);

[0062] The catalyst is zinc oxide;

[0063] The antioxidant 2# is antioxidant 1010;

[0064] The lubricant is silicone masterbatch;

[0065] The perfluoroalkyl alcohol is 2-perfluorooctylethanol;

[0066] The polypropylene grafted unsaturated carboxylic acid raw material is mechanically mixed with a catalyst, an antioxidant 2#, a lubricant, and 2-perfluorooctylethanol, and then added into a twin-screw extruder. The temperatures of zones 1 to 5 are 160° C., 180° C., 200° C., 210° C., and 220° C., respectively, and the screw speed is 400 rpm. The melt reaction is carried out, and the stranding, pelletizing, and drying are performed to obtain the easy-to-clean, scratch-resistant polypropylene material.

[0067] Example 2

[0068] The difference between Example 2 and Example 1 is that in step (1), the polypropylene is 100 parts of high-viscosity polypropylene resin, and its melt index is 10 g / 10 min.

[0069] Example 3

[0070] The difference between Example 3 and Example 1 is that in step (1), the weight portion of the unsaturated carboxylic acid is 3 parts.

[0071] Example 4

[0072] The difference between Example 4 and Example 1 is that in step (1), the weight portion of the initiator is 0.5 parts.

[0073] Example 5

[0074] The difference between Example 5 and Example 1 is that in step (1), the weight portion of the dispersion solvent is 2 parts.

[0075] Example 6

[0076] The difference between Example 6 and Example 1 is that in step (1), the weight portion of the antioxidant 1# is 0.3 parts.

[0077] Example 7

[0078] The difference between Example 7 and Example 1 is that in step (2), the weight portion of the catalyst is 0.3 parts.

[0079] Example 8

[0080] The difference between Example 8 and Example 1 is that in step (2), the weight portion of the antioxidant 2# is 1.2 parts.

[0081] Example 9

[0082] The difference between Example 9 and Example 1 is that in step (2), the weight portion of the lubricant is 2.5 parts.

[0083] Example 10

[0084] The difference between Example 10 and Example 1 is that in step (2), the weight portion of the perfluoroalkyl alcohol is 6 parts.

[0085] Embodiment 11

[0086] The difference between Example 11 and Example 1 is that in step (1), the polypropylene is a compound of a high-viscosity polypropylene resin and a low-viscosity polypropylene resin, wherein the high-viscosity polypropylene resin is 70 parts and its melt index is 2 g / 10 min; and the low-viscosity polypropylene resin is 30 parts and its melt index is 30 g / 10 min.

[0087] Example 12

[0088] The difference between Example 12 and Example 1 is that in step (1), the unsaturated carboxylic acid is replaced by crotonic acid.

[0089] Example 13

[0090] The difference between Example 13 and Example 1 is that in step (1), the initiator is replaced by tert-butyl benzoate peroxide.

[0091] Embodiment 14

[0092] The difference between Example 14 and Example 1 is that in step (1), the dispersing solvent is replaced by silicone oil.

[0093] Embodiment 15

[0094] The difference between Example 15 and Example 1 is that in step (1), the antioxidant 1# is antioxidant 1135.

[0095] Example 16

[0096] The difference between Example 16 and Example 1 is that in step (2), the catalyst is tin oxide.

[0097] Embodiment 17

[0098] The difference between Example 17 and Example 1 is that in step (2), the antioxidant 2# is antioxidant 1010 and antioxidant 168, wherein the weight portion of antioxidant 1010 is 0.15 parts, and the weight portion of antioxidant 168 is 0.15 parts.

[0099] Embodiment 18

[0100] The difference between Example 18 and Example 1 is that in step (2), the perfluoroalkyl alcohol is 2-(perfluorodecyl)ethanol, and its weight proportion is 7.8 parts.

[0101] Embodiment 19

[0102] The difference between Example 19 and Example 1 is that in step (2), the perfluoroalkyl alcohol is perfluorodecanol, and its weight proportion is 5.6 parts.

[0103] Embodiment 20

[0104] The difference between Example 20 and Example 1 is that in step (2), the perfluoroalkyl alcohol is perfluorobutanol, and its weight proportion is 2.2 parts.

[0105] Embodiment 21

[0106] The difference between Example 21 and Example 1 is that in step (1), the unsaturated carboxylic acid is itaconic acid, and its weight fraction is 1 part, and the perfluoroalkyl alcohol is 2-perfluorooctylethanol, and its weight fraction is 8 parts.

[0107] Embodiment 22

[0108] The difference between Example 22 and Example 1 is that in step (1), the unsaturated carboxylic acid is maleic anhydride, and its weight fraction is 1 part, and the perfluoroalcohol is 2-perfluorooctylethanol, and its weight fraction is 8 parts.

[0109] Comparative Example 1

[0110] Compared with Example 1, Comparative Example 1 adopts the traditional blending method, and step (1) does not need to prepare polypropylene grafted unsaturated carboxylic acid, and directly follows step (2), removing the catalyst of step (2), as follows:

[0111] Polypropylene resin 100 parts

[0112] Antioxidant 2# 0.3 parts

[0113] 0.5 parts of lubricant

[0114] 4.0 parts of perfluoroalkyl alcohol

[0115] The polypropylene resin is 100 parts of high-viscosity polypropylene resin, and its melt index is 2g / 10min;

[0116] The antioxidant 2# is antioxidant 1010;

[0117] The lubricant is silicone masterbatch;

[0118] The perfluoroalkyl alcohol is 2-perfluorooctylethanol;

[0119] The polypropylene resin, antioxidant 2#, lubricant and 2-perfluorooctylethanol are mechanically mixed and then added into a twin-screw extruder. The temperatures of zones 1 to 5 are 160° C., 180° C., 200° C., 210° C. and 220° C., respectively, and the screw speed is 400 rpm. The melt reaction is carried out, and the stranding, pelletizing and drying are performed to obtain the easy-to-clean scratch-resistant polypropylene material.

[0120] Comparative Example 2

[0121] The difference between Comparative Example 2 and Example 1 is that the ratio of perfluoroalkyl alcohol added is 0.5x.

[0122] Comparative Example 3

[0123] The difference between Comparative Example 3 and Example 1 is that the perfluoroalkyl alcohol is replaced by a fluorine auxiliary agent, specifically polytetrafluoroethylene.

[0124] Comparative Example 4

[0125] The difference between Comparative Example 4 and Comparative Example 1 is that 2-perfluorooctylethanol is first blended with polypropylene to prepare a masterbatch containing 2-perfluorooctylethanol, and then the masterbatch is implemented according to Comparative Example 1, wherein the amount of the masterbatch of 2-perfluorooctylethanol added is blended with polypropylene according to the amount of 2-perfluorooctylethanol added in Comparative Example 1.

[0126] Step 1: Prepare the masterbatch of 2-perfluorooctylethanol, blend polypropylene and 2-perfluorooctylethanol according to the following mass fractions, then add them into a twin-screw extruder, melt blend at 160°C, 180°C, 190°C, 200°C, 210°C, and a screw speed of 400rpm, and prepare the 2-perfluorooctylethanol masterbatch by extrusion, strand cutting, and drying; wherein:

[0127] Polypropylene 90 parts

[0128] 2-Perfluorooctylethanol 10 parts

[0129] Step 2: Preparation of polypropylene material: blend the 2-perfluorooctylethanol masterbatch prepared in step 1 and other components according to the following mass fractions, then add them into a twin-screw extruder, the temperatures of zones 1 to 5 are 160°C, 180°C, 200°C, 210°C, and 220°C, respectively, the screw speed is 400rpm, melt blending, extrusion, strand cutting, pelletizing, and drying to prepare a polypropylene material; wherein:

[0130] Polypropylene 60 parts

[0131] 40 parts of masterbatch of 2-perfluorooctylethanol

[0132] Antioxidant 2# 0.3 parts

[0133] 0.5 parts of lubricant

[0134] The polypropylene resin is a high-viscosity polypropylene resin with a melt index of 2g / 10min;

[0135] The antioxidant 2# is antioxidant 1010;

[0136] The lubricant is silicone masterbatch.

[0137] Performance Testing:

[0138] The mechanical properties of the products prepared in Examples 1-22 and Comparative Examples 1-4 were tested.

[0139] Test method:

[0140] Table 2 Test conditions and test standards

[0141]

[0142] The performance test results of Examples 1-22 are shown in Table 3

[0143] Table 3

[0144]

[0145] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. An easy-to-clean scratch-resistant polypropylene material, characterized in that: The easy-to-clean scratch-resistant polypropylene material is prepared from the following raw materials in parts by weight: Polypropylene grafted unsaturated carboxylic acid 100 parts Catalyst 0.05~3 parts Antioxidant 2# 0.3~1.2 parts Lubricant 0.5~2.5 parts 0.8X to 1.0X parts of perfluoroalkyl alcohol; Wherein, X=(m1 / M1×M2)×N; m1 is the added mass of the unsaturated carboxylic acid, M1 is the molecular weight of the unsaturated carboxylic acid, M2 is the molecular weight of the perfluoroalkyl alcohol, and N is the number of carboxylic acid functional groups of the unsaturated carboxylic acid; The polypropylene grafted unsaturated carboxylic acid is prepared from the following raw materials in parts by weight: Polypropylene resin 100 parts Unsaturated carboxylic acid 1-5 parts Initiator 0.2~0.5 parts Dispersing solvent 1-2 parts Antioxidant 1# 0.1-0.3 parts.

2. The easy-to-clean scratch-resistant polypropylene material according to claim 1, characterized in that: The preparation method of polypropylene grafted unsaturated carboxylic acid comprises the following steps: Unsaturated carboxylic acid, initiator and antioxidant 1# are added to the dispersion solvent and stirred to prepare a mixed solution. The mixed solution is mixed with polypropylene resin particles and then added to a twin-screw extruder for mixing, melting, extruding and granulation to obtain polypropylene grafted unsaturated carboxylic acid.

3. The easy-to-clean scratch-resistant polypropylene material according to claim 1, characterized in that: The polypropylene resin comprises the following components in parts by weight: High viscosity polypropylene resin 70-100 parts Low viscosity polypropylene resin 0-30 parts The high viscosity polypropylene resin has a melt index of 2 to 10 g / 10 min when tested at 230° C.×2.16 kg. The low-viscosity polypropylene resin has a melt index of 30 to 100 g / 10 min when tested under the conditions of 230° C.×2.16 kg.

4. The easy-to-clean scratch-resistant polypropylene material according to claim 1, characterized in that: The unsaturated carboxylic acid includes at least one of acrylic acid, crotonic acid, itaconic acid and maleic anhydride.

5. The easy-to-clean scratch-resistant polypropylene material according to claim 1, characterized in that: The initiator includes at least one of diisopropylbenzene peroxide, tert-butyl peroxybenzoate, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, and di-tert-butyl diisopropylbenzene peroxide; The dispersing solvent includes soybean oil and / or dimethyl silicone oil; The antioxidant 1# is antioxidant 5057 or antioxidant 1135.

6. The easy-to-clean scratch-resistant polypropylene material according to claim 1, characterized in that: The catalyst is one of zinc oxide, tin oxide and antimony trioxide.

7. The easy-to-clean scratch-resistant polypropylene material according to claim 1, characterized in that: The antioxidant 2# is one or two of antioxidant 1010, antioxidant 168, and antioxidant 1076; and the lubricant is silicone masterbatch.

8. The easy-to-clean scratch-resistant polypropylene material according to claim 1, characterized in that: The perfluoroalkyl alcohol is at least one of 2-perfluorooctylethanol, 2-(perfluorodecyl)ethanol, perfluorodecanol and perfluorobutanol.

9. A method for preparing an easy-to-clean scratch-resistant polypropylene material as claimed in any one of claims 1 to 8, characterized in that: The steps include: The polypropylene grafted unsaturated carboxylic acid is mixed evenly with perfluoroalkyl alcohol, catalyst, antioxidant 2# and lubricant, added into a twin-screw extruder for mixing, melting, extruding and reacting, and granulating to obtain the easy-to-clean scratch-resistant polypropylene material.

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