Organosilicon master batch with improved machinability and bicontinuous phase structure and preparation method thereof

Abstract

The invention provides an organic silicon master batch with an improved processability and a bicontinuous phase structure and a preparation method thereof, and the organic silicon master batch mainly comprises the following raw materials in parts by weight: 47-48 parts of ultra-high molecular weight solid organic silicon, 47-48 parts of polypropylene, 2-3 parts of amino silicon oil and 2-3 parts of maleic anhydride grafted polypropylene, the ultra-high molecular weight solid organic silicon is solid polydimethylsiloxane with the molecular weight of at least 80,000. According to the organic silicon master batch, solid organic silicon with ultra-high molecular weight and polypropylene are selected as base materials, and amino silicon oil and maleic anhydride grafted polypropylene in a specific proportion are selected as auxiliaries, so that a unique bicontinuous phase structure is formed. The formation of the bicontinuous phase structure shows that the organic silicon is uniformly dispersed in polyolefin, the phase interface combination is tight, and the processing performance of a polyolefin composite material can be obviously improved when the organic silicon master batch is applied to the field of plastic processing.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of silicone masterbatch for plastic processing, and relates to a silicone masterbatch with a bicontinuous phase structure and improved processability and a preparation method thereof. BACKGROUND

[0002] In a polyolefin-based composite material, a specific filler is often added to make it functional, but a high filling amount of the filler usually leads to a decrease in processability, easily causing equipment blockage or being unable to be extruded and processed.

[0003] Silicone (polydimethylsiloxane) is a polymer formed by alternating arrangement of silicon atoms and oxygen atoms, and has characteristics such as high thermal stability, high flexibility and high elasticity. Therefore, silicone of various molecular weights is often added to polyolefins as a lubricant to improve the processability, surface properties and wear resistance of polyolefin blends. However, due to poor compatibility between the silicone chain and the polyolefin chain and weak interfacial action, the microphase structure presents a separated two-phase structure. This leads to poor dispersibility of the silicone chain in the polyolefin, easy migration and phase separation, and often affects the performance of the silicone in modification. SUMMARY

[0004] To solve the problems in the prior art, the application provides a silicone masterbatch with a bicontinuous phase structure and improved processability and a preparation method thereof. The silicone masterbatch forms a unique bicontinuous phase structure by selecting solid-state silicone with ultrahigh molecular weight and polypropylene as base materials, and a specific proportion of amino silicone oil and maleic anhydride grafted polypropylene as an additive. The formation of the bicontinuous phase structure indicates that the silicone is uniformly dispersed in the polyolefin and the phase interface is tightly combined. The silicone masterbatch can be applied to the field of plastic processing to significantly improve the processability of polyolefin composites.

[0005] To achieve the above-mentioned purpose, the application is implemented by adopting the technical scheme of the following technical measures.

[0006] In one aspect, the application provides a silicone masterbatch with a bicontinuous phase structure and improved processability, and raw materials thereof mainly include the following components in parts by weight:

[0007]

[0008] The total amount of the ultrahigh molecular weight solid-state silicone, the polypropylene, the amino silicone oil and the maleic anhydride grafted polypropylene is 100 parts.

[0009] The ultrahigh molecular weight solid-state silicone is solid-state polydimethylsiloxane with a molecular weight of at least 0.8 million.

[0010] Generally, the improvement of the processability of the silicone masterbatch with the bicontinuous phase structure is prepared by the conventional production process of the silicone masterbatch in the prior art, i.e. the silicone masterbatch is prepared by the conventional melt extrusion granulation, such as the twin-screw extrusion granulation. However, it should be noted that the lower limit of the melt processing temperature of the polypropylene is generally higher than that of the ultra-high molecular weight solid silicone according to the main raw material components provided by the present application based on the common knowledge, for example, the melt processing temperature of the conventional polypropylene chemical raw material in the market is generally about 180-230℃, and the melt processing temperature of the ultra-high molecular weight solid silicone in the market is generally about 120-250℃, so that the sufficient melt processing temperature of the polypropylene should be met in the preparation method of the silicone masterbatch prepared by the melt extrusion granulation, for example, the melt extrusion granulation process of the polypropylene in the prior art is directly referred to.

[0011] In order to better illustrate the present application, and provide a technical solution for reference, the present application further provides a preparation method of the silicone masterbatch with the bicontinuous phase structure and improved processability, which mainly comprises the following steps:

[0012] (1) The raw materials mainly comprising the following components are prepared by weight fraction:

[0013]

[0014] The total amount of the ultra-high molecular weight solid silicone, the polypropylene, the amino silicone oil and the maleic anhydride grafted polypropylene is 100 parts;

[0015] The ultra-high molecular weight solid silicone is a solid polydimethylsiloxane with a molecular weight of at least 800,000.

[0016] (2) After the raw materials prepared in step (1) are uniformly mixed, the twin-screw extrusion platform is added, and after the melt extrusion, water cooling and strand cutting, the silicone masterbatch is obtained.

[0017] The process parameters of the twin-screw extrusion platform are as follows: the extrusion temperature is 170-180℃, and the rotation speed is 30-50r / min.

[0018] The main point of the present application is that when the ultra-high molecular weight solid silicone and the polypropylene are used as the base material, the blend shows a typical incompatible two-phase structure, and it is found that after the addition of the amino silicone oil and the maleic anhydride grafted polypropylene as the additive in a specific proportion, the silicone masterbatch with the bicontinuous phase structure is prepared by the melt extrusion granulation.

[0019] It should be noted that based on the common knowledge in the art, it is known that the polarity difference between the silicone chain and the carbon chain of the polyolefin is large, and the mixing enthalpy is positive, resulting in a thermodynamically incompatible two-phase structure of silicone and polyolefin. In the past prior art, due to the fact that the silicone and polyolefin system cannot form a bicontinuous phase structure, the agglomeration caused by poor dispersibility greatly affects the product lubrication and the effect of improving processability.

[0020] However, the inventors of the present application accidentally discovered that by adding amino silicone oil and maleic anhydride grafted polypropylene as an additive, and then preparing silicone master batches by melt extrusion granulation, and observing the morphology by scanning electron microscope, it was found that a characteristic bicontinuous phase structure was formed.

[0021] Based on this experimental phenomenon, through comparative test analysis, it is determined that only the simultaneous addition of amino silicone oil and maleic anhydride grafted polypropylene can produce silicone master batches with a bicontinuous phase structure. Therefore, the inventors believe that the mechanism of forming a bicontinuous phase structure is as follows: Figure 1 As shown in the figure, during the extrusion process, the polypropylene segments of the additive maleic anhydride grafted polypropylene and the base polypropylene are thermodynamically compatible, the segments are entangled with each other, the silicon chains in the additive amino silicone oil and the base ultrahigh molecular weight solid silicone are thermodynamically compatible, the segments are entangled with each other, and the maleic anhydride groups in the maleic anhydride grafted polypropylene react with the amino groups in the amino silicone oil, which greatly improves the compatibility of silicone and polypropylene, and promotes the phase structure of the blend to cross over, i.e. from a typical two-phase structure to a bicontinuous phase structure.

[0022] However, it should be emphasized that based on the theoretical research of the current prior art, the skilled person in the art cannot directly infer whether the melt blending and extrusion composite has a bicontinuous phase structure based on the specific selection of the two-phase base or the modification selection. It can only be determined whether it has a bicontinuous phase structure through objective experimental evidence. Therefore, the above mechanism is based on the objective experimental evidence and is deduced. This also explains why the bicontinuous phase structure, which has significant advantages, is still rarely reported in functional composites in this technical field.

[0023] Based on the above accidental discovery, through further variable comparative test analysis, it is confirmed that the characteristic of the bicontinuous phase structure appears only when amino silicone oil and maleic anhydride grafted polypropylene are added at the same time, and the ratio of the two needs to be further limited, otherwise the prepared comparative silicone master batch product appears a feature in the process of transforming from a non-bicontinuous phase structure to a bicontinuous phase structure in the micro-morphology, but in a strict sense, it still belongs to a non-bicontinuous phase.

[0024] In the present text, the ultra-high molecular weight solid organosilicon is a solid polydimethylsiloxane with a molecular weight of at least 800,000, which can be directly obtained from the market; it is to be noted that the solid polydimethylsiloxane is limited to be used in the present application, on the one hand, because its density is similar to that of the conventional polypropylene industrial raw material, which is beneficial to the formation of a bicontinuous phase structure; on the other hand, when liquid polydimethylsiloxane (silicone oil) is used, it is difficult to avoid the migration and precipitation of the silicone oil in the polyolefin.

[0025] In the present text, the polypropylene is selected from the conventional polypropylene industrial raw materials, and those skilled in the art can select a suitable polypropylene raw material according to the actual product requirements or process requirements.

[0026] In one preferred technical solution, in order to enhance the melt flowability of the prepared organosilicon master batch, so as to facilitate the better dispersion of the organosilicon master batch product in use, the polypropylene used in the following examples has a spinning grade polypropylene with a melt index of 36 g / 10 min.

[0027] In the present text, the amino silicone oil is an aminopropyl double-terminated polydimethylsiloxane, CAS: 106214-84-0, which is a conventional industrial additive and can be directly obtained from the market.

[0028] In the present text, the maleic anhydride grafted polypropylene is a conventional industrial additive and can be directly obtained from the market.

[0029] In one preferred technical solution, in step (2), the prepared raw materials in step (1) are uniformly mixed, in order to improve the mixing efficiency of the raw materials, the prepared raw materials are preferably pre-mixed, then subjected to freezing treatment (for example, immersed in liquid nitrogen for freezing treatment under laboratory conditions), and then added into a high-speed mixer for mixing for at least 40 seconds.

[0030] Generally, the process parameters of the twin-screw extrusion platform in step (2) include the process conditions / steps for conventional melt extrusion granulation, in addition to the extrusion temperature and rotation speed defined in the present application, and those skilled in the art can directly refer to the conventional preparation method of the existing organosilicon master batch.

[0031] In the present text, the mixing, water cooling and strand cutting all follow the conventional principles in chemical processes, and those skilled in the art can perform specific operations according to common knowledge.

[0032] The present application has the following beneficial effects:

[0033] 1. The present application provides a kind of organic silicon master batch with bicontinuous phase structure for improving processability, which is formed by selecting solid-state organic silicon with ultrahigh molecular weight and polypropylene as base material, with specific proportion of amino silicone oil and maleic anhydride grafted polypropylene as auxiliary agent, to form a unique bicontinuous phase structure. The formation of the bicontinuous phase structure indicates that the organic silicon is uniformly dispersed in the polyolefin, and the phase interface is tightly combined. The application of the organic silicon master batch in the field of plastic processing can realize the obvious improvement of the processing performance of polyolefin composite materials.

[0034] 2. The present application provides a kind of organic silicon master batch with bicontinuous phase structure for improving processability, which is found that only by adding specific proportion of amino silicone oil and maleic anhydride grafted polypropylene as auxiliary agent, through melt extrusion granulation, the organic silicon master batch with distinct bicontinuous phase structure characteristics is prepared. In one of the application methods, it can significantly improve the processing performance of polyolefin-based composite materials as a lubricant, and has certain economic value. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The schematic diagram of the bicontinuous phase structure of the organic silicon master batch prepared in Example 1 of the present application.

[0036] Figure 2 The actual photo of the organic silicon master batch prepared in Example 1 of the present application.

[0037] Figure 3 The scanning electron microscope comparison chart of the samples prepared in Example 1 and Comparative Examples 1-5 of the present application.

[0038] Figure 4 The torque rheology comparison data chart of the polypropylene / 70wt% boron carbide blend particles prepared in Application Example 1 and Application Comparative Example 1 of the present application. Among them, PP / B4C-70 refers to the polypropylene / 70wt% boron carbide blend particles prepared in Application Comparative Example 1, and PP / UHMWPDMS@PP / B4C-70 refers to the polypropylene / 70wt% boron carbide blend particles prepared in Application Example 1.

[0039] Figure 5 The photo of the sample bar prepared in Application Examples 1-2 and Comparative Application Example 1 during impact performance test. DETAILED DESCRIPTION

[0040] For a further understanding of the present application, preferred embodiments thereof will be described in conjunction with examples, it should be understood, however, that these are designed merely to further illustrate the features and advantages of the present application, and do not limit the scope of the claims. Those skilled in the art can make appropriate modifications to the process parameters based on the content herein. It is particularly pointed out that all such similar alterations and modifications that are obvious to one skilled in the art are to be included within the true spirit and scope of the present application. The methods and applications of the present application have been described by preferred embodiments, and the relevant personnel can obviously make modifications or appropriate changes and combinations to the methods and applications described herein without departing from the content, spirit and scope of the present application, to realize and apply the present application technology. Although it is believed that the following terms are well known to those skilled in the art, the following definitions are set forth to facilitate the understanding of the subject matter disclosed herein.

[0041] In one aspect, the present application provides an improved processability silicone masterbatch having a bicontinuous phase structure, which raw materials mainly include the following components by weight fraction:

[0042] Ultra-high molecular weight solid silicone 47-48 parts,

[0043]

[0044] The total amount of the ultra-high molecular weight solid silicone, polypropylene, amino silicone oil and maleic anhydride grafted polypropylene is 100 parts.

[0045] The ultra-high molecular weight solid silicone is a solid polydimethylsiloxane with a molecular weight of at least 800,000.

[0046] Generally, the improved processability silicone masterbatch having a bicontinuous phase structure provided by the present application can be directly prepared by referring to the conventional silicone masterbatch production process in the prior art, i.e. by conventional melt extrusion granulation to prepare the silicone masterbatch, such as twin-screw extrusion granulation. It should be noted that based on the main raw material component composition provided by the present application, it is known to those skilled in the art that the lower limit of the melt processing temperature of polypropylene is generally higher than that of ultra-high molecular weight solid silicone, for example, the melt processing temperature of conventional polypropylene chemical raw materials on the market is generally about 180-230°C, while the melt processing temperature of commercially available ultra-high molecular weight solid silicone is generally about 120-250°C, therefore in order to meet the sufficient melt processing temperature of polypropylene in the preparation method for preparing the silicone masterbatch by melt extrusion granulation, the melt extrusion granulation process of polypropylene in the prior art is directly referred to.

[0047] In order to better illustrate the present application and provide a reference embodiment, the present application further provides a preparation method of an improved processability silicone masterbatch having a bicontinuous phase structure, which mainly includes the following steps:

[0048] (1) by weight, the raw materials mainly including the following components are prepared:

[0049]

[0050] The total amount of the ultra-high molecular weight solid silicone, polypropylene, amino silicone oil and maleic anhydride grafted polypropylene is 100 parts;

[0051] The ultra-high molecular weight solid silicone is a solid polydimethylsiloxane with a molecular weight of at least 800,000.

[0052] (2) After the raw materials prepared in step (1) are uniformly mixed, they are added to a twin-screw extrusion platform, and after melt extrusion, water cooling and strand cutting, the silicone masterbatch is obtained.

[0053] The process parameters of the twin-screw extrusion platform are: extrusion temperature 170-180℃, rotation speed 30-50r / min.

[0054] The main point of the present application is that when the ultra-high molecular weight solid silicone and polypropylene are used as the base material, the blend shows a typical incompatible two-phase structure. It is found that after adding a specific proportion of amino silicone oil and maleic anhydride grafted polypropylene as an additive, a silicone masterbatch with a distinctive double-continuous phase structure is prepared by melt extrusion and granulation.

[0055] It should be noted that based on the common knowledge in the art, it is known that the polarity difference between the silicone chain and the carbon chain of polyolefin is large, and the mixing enthalpy is positive, resulting in a thermodynamically incompatible two-phase structure of silicone and polyolefin. In the past existing technology, due to the fact that the silicone and polyolefin system cannot form a double-continuous phase structure, the agglomeration caused by poor dispersibility greatly affects the product lubrication and the effect of improving processability.

[0056] However, the inventors of the present application accidentally found that by adding amino silicone oil and maleic anhydride grafted polypropylene as an additive, a silicone masterbatch prepared by melt extrusion and granulation has a distinctive double-continuous phase structure when its morphology is observed by scanning electron microscopy.

[0057] Based on this experimental phenomenon, through comparative test analysis, it is determined that only the simultaneous addition of amino silicone oil and maleic anhydride grafted polypropylene can prepare a silicone masterbatch with a double-continuous phase structure. Therefore, the inventors believe that the mechanism of forming a double-continuous phase structure is as follows: Figure 1As shown, in the extrusion process, the polypropylene segments of the maleic anhydride grafted polypropylene and the base polypropylene are thermodynamically compatible, the segments are intertwined with each other, the silicon chains in the amino silicone oil and the base ultrahigh molecular weight solid silicone are thermodynamically compatible, the segments are intertwined with each other, and the maleic anhydride groups in the maleic anhydride grafted polypropylene and the amino groups in the amino silicone oil react, which greatly improves the compatibility of the silicone and the polypropylene, and causes the phase structure of the blend to change, i.e., from a typical two-phase structure to a bicontinuous phase structure.

[0058] However, it should be emphasized that based on the theoretical research of the current prior art, the person skilled in the art cannot directly infer whether the melt blending extrusion composite has the characteristics of a bicontinuous phase structure based on the specific selection of the two-phase base or the modification selection, but can only determine whether it has a bicontinuous phase structure through objective experimental evidence. Therefore, the above mechanism speculation is based on the objective experimental evidence. This also explains why the bicontinuous phase structure is rarely reported in the functional composite materials in the technical field despite its significant advantages.

[0059] And on the basis of the above-mentioned accidental discovery, through further variable comparison test analysis, it is confirmed that the characteristics of the bicontinuous phase structure appear only when the amino silicone oil and the maleic anhydride grafted polypropylene are added at the same time, and the ratio of the two needs to be further limited, otherwise the prepared silicone master batch product appears the characteristics in the process of changing from a non-bicontinuous phase structure to a bicontinuous phase structure in the micro-morphology, but in a strict sense, it still belongs to a non-bicontinuous phase.

[0060] In this paper, the ultrahigh molecular weight solid silicone is a solid polydimethylsiloxane with a molecular weight of at least 800,000, which can be obtained directly from the market; it should be noted that in this invention, solid polydimethylsiloxane is used, on the one hand, because its density is similar to that of conventional polypropylene industrial raw materials, which is beneficial to the formation of a bicontinuous phase structure; on the other hand, when liquid polydimethylsiloxane (silicone oil) is used, it is difficult to avoid the migration and precipitation of silicone oil in polyolefin.

[0061] In this paper, the polypropylene is a conventional polypropylene industrial raw material, and the person skilled in the art can select the appropriate polypropylene raw material according to the actual product demand or process requirements.

[0062] In one preferred embodiment, in order to enhance the melt flowability of the prepared silicone master batch, so as to facilitate the dispersion of the silicone master batch product in use, the polypropylene used in the following examples is a spinning grade polypropylene with a melt index of 36 g / 10 min.

[0063] In the present application, the amino silicone oil is aminopropyl bis-terminated polydimethylsiloxane, CAS: 106214-84-0, which is a common industrial additive and can be directly obtained from the market.

[0064] In the present application, the maleic anhydride grafted polypropylene is a common industrial additive and can be directly obtained from the market.

[0065] In one preferred embodiment, the prepared raw materials in step (1) are mixed uniformly in step (2). In order to improve the mixing efficiency of the raw materials, the prepared raw materials are preferably pre-mixed, then frozen (for example, immersed in liquid nitrogen for freezing treatment under laboratory conditions), and then mixed in a high-speed mixer for at least 40 seconds.

[0066] Generally, the process parameters of the twin-screw extrusion platform in step (2) include the process conditions / steps for conventional melt extrusion granulation, in addition to the extrusion temperature and rotation speed defined in the present application. Those skilled in the art can directly refer to the conventional preparation method of existing silicone masterbatch.

[0067] In the present application, the mixing, water cooling, and strand cutting all follow the conventional principles in chemical processes, and those skilled in the art can perform specific operations according to common knowledge.

[0068] The present application will be further explained in detail with reference to the following examples. However, those skilled in the art will understand that these examples are provided only for illustrative purposes, and are not intended to limit the scope of the present application.

[0069] Example

[0070] The embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are provided only for illustrative purposes, and should not be considered as limiting the scope of the present application. If no specific conditions are specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. If no manufacturer of the reagent or instrument is specified, it is a conventional product that can be obtained from the market. The present application should not be interpreted as being limited to the specific examples described.

[0071] 1. Raw materials

[0072] Ultra-high molecular weight polydimethylsiloxane (Ultra-high molecular weight polydimethylsiloxane), RGB-0802, molecular weight about one million, Dow Corning Company;

[0073] Polypropylene (Polypropylene), PP3155E3, Exxon Mobil Corporation;

[0074] Aminopropyl terminated polydimethylsiloxane, Shanghai Maikelin Biochemical Technology Co., Ltd.

[0075] Maleic anhydride grafted polypropylene, Dongguan Dinghai Plastic Chemical Co., Ltd.

[0076] 2. Preparation method

[0077] (1) The raw materials mainly including the following components are prepared by weight fraction:

[0078] Ultra-high molecular weight polydimethylsiloxane 47-48 parts,

[0079] Polypropylene 47-48 parts,

[0080] Amino silicone oil 2-3 parts,

[0081] Maleic anhydride grafted polypropylene 2-3 parts,

[0082] The total amount of the ultra-high molecular weight solid silicone, polypropylene, amino silicone oil and maleic anhydride grafted polypropylene is 100 parts;

[0083] (2) The raw materials prepared are first premixed, then soaked in liquid nitrogen for freezing treatment for 10 seconds, then added to a high-speed mixer and mixed for 40 seconds, then added to a twin-screw extrusion platform, and then subjected to melt extrusion, water cooling, and strand cutting to obtain the silicone master batch;

[0084] The process parameters of the twin-screw extrusion platform are: extrusion temperature 180℃, rotation speed 30r / min.

[0085] 3. Test method

[0086] Infrared spectrum is measured by using a Nicolet is50 Fourier transform infrared spectrometer of Thermo Scientific Company.

[0087] Morphology structure is observed by using an Apreo S HiVoc scanning electron microscope of Thermo Scientific Company.

[0088] Torque rheological property is measured by using an RM-200C torque rheometer of Haap Company, and the rotor torque of different samples is tested at a speed of 30r / min.

[0089] Melt index is determined by using an XNR-400 melt index instrument.

[0090] Notched impact performance was determined using a Zwick GmbH impact testing machine according to ISO 179 standard.

[0091] Examples 1-2, Comparative Examples 1-5

[0092] Examples 1-2 and Comparative Examples 1-5 used organosilicon masterbatches prepared according to the steps in "2. Preparation Method" above as samples, and used the raw materials of each component in step (1) as variables, as shown in Table 1 below. The morphology and structure of the samples were observed by scanning electron microscopy to determine whether they had a bicontinuous phase structure. Figure 3 As shown.

[0093] Table 1 shows the raw materials of different components in Examples 1-2 and Comparative Examples 1-5 as variables.

[0094]

[0095] pass Figure 3 It is evident that Example 1 exhibits a bicontinuous phase structure with a tight interfacial bond between the two phases. Comparative Example 1, lacking both amino silicone oil and maleic anhydride-grafted polypropylene, displays a non-bicontinuous phase structure with numerous defects and voids. Comparative Example 2, containing only amino silicone oil, and Comparative Example 3, containing only maleic anhydride-grafted polypropylene, also exhibit non-bicontinuous phase structures. In Comparative Examples 4 and 5, the ratios of amino silicone oil to maleic anhydride-grafted polypropylene are 3:1 and 1:3, respectively. These ratios indicate phase structures intermediate between those of Example 1 and Comparative Examples 2 and 3, but still show non-bicontinuous phase characteristics.

[0096] Application Example 1

[0097] Application Example 1 uses the organosilicon masterbatch prepared in Example 1 as a lubricating masterbatch to prepare polypropylene / 70wt% boron carbide blend particles as a sample. The main steps include:

[0098] (1) Prepare the raw materials, which mainly include the following components, by weight:

[0099]

[0100] (2) After the raw materials prepared in step (1) are mixed evenly, they are added to the twin-screw extrusion platform, melt extrusion, water cooling, and strip cutting to obtain polypropylene / 70wt% boron carbide blend particles.

[0101] The process parameters for the twin-screw extrusion platform are: extrusion temperature 190℃, rotation speed 30r / min.

[0102] Application Example 2

[0103] Application Example 2 is to use the silicone masterbatch prepared in Example 2 as lubricating masterbatch to prepare polypropylene / 70wt% boron carbide blend particles as sample, which mainly includes the following steps:

[0104] (1) The raw materials mainly including the following components are prepared by weight fraction:

[0105]

[0106] (2) After the raw materials prepared in step (1) are uniformly mixed, they are added to a twin-screw extrusion platform, and after melt extrusion, water cooling, and strand cutting, polypropylene / 70wt% boron carbide blend particles are obtained;

[0107] The process parameters of the twin-screw extrusion platform are: extrusion temperature 190℃, rotation speed 30r / min.

[0108] Application Comparative Example 1

[0109] Application Comparative Example 1 is to prepare polypropylene / 70wt% boron carbide blend particles without adding the silicone masterbatch prepared in Examples 1 and 2, which mainly includes the following steps:

[0110] (1) The raw materials mainly including the following components are prepared by weight fraction:

[0111] Polypropylene 30 parts,

[0112] Boron carbide 70 parts,

[0113] (2) After the raw materials prepared in step (1) are uniformly mixed, they are added to a twin-screw extrusion platform, and after melt extrusion, water cooling, and strand cutting, polypropylene / 70wt% boron carbide blend particles are obtained;

[0114] The process parameters of the twin-screw extrusion platform are: extrusion temperature 190℃, rotation speed 30r / min.

[0115] In order to facilitate the notched impact performance test, the polypropylene / 70wt% boron carbide blend particles prepared in Application Examples 1-2 and Application Comparative Example 1 are hot-pressed into sample bars conforming to ISO 179 standard. The specific hot-pressing process parameters are: hot-pressed at 180℃, pressure 10MPa, pressure holding time 10min, and after cooling, cold-pressed for 3min to obtain the sample bars.

[0116] For example, Figure 4Comparing the polypropylene / 70wt% boron carbide blend particles prepared by application example 1 and application comparative example 1 with Table 2, it can be seen from the rheological properties that the rotor torque of application comparative example 1 without adding the silicone masterbatch prepared in example 1 is 7.7Nm, while the rotor torque of application example 1 with adding the silicone masterbatch prepared in example 1 is 6.3Nm; similarly, the rotor torque of application example 2 with adding the silicone masterbatch prepared in example 2 is 6.5Nm, which shows that the silicone masterbatch prepared in the application reduces the viscosity of the blend and achieves the lubricating effect when used as a lubricating masterbatch.

[0117] Further comparing the impact properties of the samples prepared in application examples 1-2 and application comparative example 1, it can be seen that the notched impact strength of the blend of the sample prepared in application comparative example 1 is 1.6KJ / m 2 , while the notched impact strength of the sample prepared in application example 1 is 1.9KJ / m 2 , and the notched impact strength of the sample prepared in application example 2 is 2.2KJ / m 2 , which shows that adding the product improves the impact resistance of the polypropylene / boron carbide filler blend.

[0118] Table 2 Comparison of rotor torque and notched impact strength of the samples prepared in application examples 1-2 and application comparative example 1

[0119]

[0120] The above examples are the preferred embodiments of the application, but the embodiments of the application are not limited by the above examples, and any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the application are equivalent replacement methods and are included in the protection scope of the application.

Claims

1. A silicone masterbatch having a bicontinuous phase structure with improved processability, characterized in that The raw materials mainly include the following components by weight: The total amount of the super high molecular weight solid silicone, polypropylene, amino silicone oil and maleic anhydride grafted polypropylene is 100 parts. The super high molecular weight solid silicone is solid polydimethylsiloxane with a molecular weight of at least 800,000.

2. The silicone masterbatch of claim 1, wherein: The polypropylene is a spinning grade polypropylene with a melt index of 36 g / 10 min.

3. A process for the preparation of an organosilicon masterbatch having a bicontinuous phase structure with improved processability, characterized in that The method mainly includes the following steps: (1) The raw materials mainly including the following components by weight are prepared: The total amount of the super high molecular weight solid silicone, polypropylene, amino silicone oil and maleic anhydride grafted polypropylene is 100 parts. The super high molecular weight solid silicone is solid polydimethylsiloxane with a molecular weight of at least 800,000. (2) After the raw materials prepared in step (1) are uniformly mixed, they are added to a twin-screw extrusion platform, and then melt extruded, water cooled and strand cut to obtain the silicone master batch. The process parameters of the twin-screw extrusion platform are: extrusion temperature 170-180℃, and rotation speed 30-50 r / min.

4. The method of claim 3, wherein: In step (2), the raw materials prepared in step (1) are first premixed, then frozen, and then mixed in a high-speed mixer for at least 40 seconds.

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