A PPS composition and its preparation method

Abstract

The present invention discloses a PPS composition and a preparation method thereof, belonging to the technical field of polymer materials. In this product, a specific type of siloxane is introduced into the PPS matrix for compounding. Meanwhile, under the action of a nucleating agent, the toughness and elongation at break of the PPS matrix are achieved without introducing a toughening agent. Moreover, the product can maintain a high tensile strength, has a high crystallization temperature, and can be applied to scenarios at relatively high temperatures.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and particularly relates to a PPS composition and a preparation method thereof. Background Art

[0002] PPS is a common engineering thermoplastic polyether plastic, but the initial toughness performance of this plastic is not sufficient to match the application field. Therefore, a toughening agent is introduced into the product to improve the toughness, impact resistance strength, and elongation at break of the product.

[0003] However, the introduction of the existing toughening agent will cause the tensile strength of the prepared PPS composite material to decrease, and the crystallization temperature will also decrease, resulting in a significant decrease in the processing performance and molding performance of the product at high temperatures, and the application scenarios are greatly limited. Summary of the Invention

[0004] Based on the defects existing in the prior art, the purpose of the present invention is to provide a PPS composition. In this product, a specific type of siloxane is introduced into the PPS matrix for compounding. At the same time, under the action of a nucleating agent, the toughness and elongation at break of the PPS matrix are achieved without introducing a toughening agent. Moreover, the product can maintain a high tensile strength and a high crystallization temperature, and can be applied to scenarios at relatively high temperatures.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A PPS composition, comprising the following components in parts by weight:

[0007] 95 - 99 parts of PPS resin, 0.5 - 2 parts of nucleating agent, and 0.5 - 2 parts of siloxane;

[0008] The PPS resin is a linear polyphenylene sulfide resin, and the melt flow rate at 316°C and 5 kg load is ≤250 g / 10 min;

[0009] The siloxane is a linear siloxane containing terminal epoxy groups and / or terminal amino groups.

[0010] Preferably, the melt flow rate of the PPS resin is obtained by testing according to ISO1133:2011.

[0011] Preferably, the melt flow rate of the PPS resin at 316°C and 5 kg load is 70 - 250 g / 10 min;

[0012] More preferably, the melt flow rate of the PPS resin at 316 °C and a load of 5 kg is in the range of one or both of 70 g / 10 min, 100 g / 10 min, 120 g / 10 min, 150 g / 10 min, 180 g / 10 min, 200 g / 10 min, 220 g / 10 min, and 250 g / 10 min.

[0013] More preferably, the melt flow rate of the PPS resin at 316 °C and a load of 5 kg is 100 - 180 g / 10 min.

[0014] In the prior art, in order to ensure that the product has sufficient toughness, people have introduced toughening agents such as hyperbranched polyester, nylon, or terpolymers into the PPS composition. However, the introduction of these substances will disrupt the crystallization behavior of the PPS resin, resulting in fewer and smaller crystal numbers. Therefore, the toughness of the product is improved, the crystallization temperature is reduced, the molding time is prolonged, and at the same time, the demolding difficulty during product processing increases, and flash is likely to occur. Therefore, in the PPS composition of the present invention, the inventor uses a linear PPS resin with specific fluidity as the matrix resin, and at the same time compound a nucleating agent and a linear siloxane with specific end groups. The epoxy group / amine group on the end of the siloxane will react with the linear PPS resin, increasing the molecular weight of the PPS resin and disturbing the molecular structure. The nucleating agent will further refine the crystal grains under this modification, promoting the lamellar drift during the stretching process, and finally achieving a toughening function similar to that of the toughening agent. However, due to the different modification paths, the crystallization behavior of the PPS resin in the PPS composition still proceeds normally, so the product has sufficient tensile strength and crystallization temperature.

[0015] In the product of the present invention, the melt flow rate of the PPS resin cannot be too high. In addition to being related to the intrinsic toughness and rigidity of the product, the reaction degree of PPS resins with different melt flow rates and the siloxane is also different. The rigidity and toughness of the product may not be ideal after the introduction of the siloxane and the nucleating agent for modification with inappropriate PPS resins. On the other hand, since only the use of linear siloxane and linear PPS resin can achieve the modification of the PPS resin with the special mechanism described in the present invention, if siloxanes and PPS resins with other structures are used, the same modification effect cannot be achieved.

[0016] Preferably, the PPS composition comprises the following components in parts by weight:

[0017] 97 - 99 parts of PPS resin, 0.8 - 1 part of nucleating agent, and 0.8 - 1.5 parts of siloxane.

[0018] Preferably, the dynamic viscosity of the siloxane at 25 °C is 100 - 900 mPa*s.

[0019] More preferably, the dynamic viscosity of the siloxane at 25 °C is one of 100 mPa·s, 200 mPa·s, 300 mPa·s, 400 mPa·s, 500 mPa·s, 600 mPa·s, 700 mPa·s, 800 mPa·s, 900 mPa·s or a range value of any two of them.

[0020] More preferably, the dynamic viscosity of the siloxane at 25 °C is 145 to 500 Pa·s.

[0021] Preferably, the test method for the dynamic viscosity of the siloxane is HG / T 2363:1992.

[0022] Different from conventional siloxanes, the viscosity change of linear siloxanes may be related to the degree of modification of PPS resin in the present invention. Siloxanes with viscosities in the preferred above ranges have more sufficient end groups and structural stability, resulting in a better degree of modification of PPS resin.

[0023] Preferably, the molecular structure of the siloxane is:

[0024]

[0025] Among them, R is an amino group and / or an epoxy group, and n = 1 to 1000;

[0026] More preferably, the weight-average molecular weight of the siloxane is 3500 to 25000;

[0027] The weight-average molecular weight of the siloxane is directly measured by gel permeation chromatography.

[0028] Preferably, the siloxane is bis(3-aminopropyl) terminated polydimethylsiloxane.

[0029] Preferably, the nucleating agent is at least one of an inorganic nucleating agent and an organic nucleating agent.

[0030] More preferably, the inorganic nucleating agent is at least one of zinc oxide, boron nitride, talc, kaolin, aluminum oxide, silicon dioxide, calcium oxide, and titanium dioxide.

[0031] More preferably, the organic nucleating agent is a liquid crystal polymer.

[0032] More preferably, the liquid crystal polymer is an aromatic polyester.

[0033] More preferably, the aromatic polyester is a liquid crystal polymer. Preferably, the melting point of the liquid crystal polymer is 280-320 °C. For example, the liquid crystal polymer can be the thermotropic liquid crystal polymer containing a sulfone group structure described in CN109777105B. The molecular structure is as follows, the ratio of n:m is (6:1)-(3:1), and the melting point is 280-320 °C;

[0034]

[0035] Wherein R1 is a meta-phenyl group or a combination of a meta-phenyl group and a para-phenyl group, and R2 and R3 are at least one of a phenyl group and a biphenyl group.

[0036] Preferably, the nucleating agent is a compound of an inorganic nucleating agent and an organic nucleating agent, and the mass ratio of the two is (9:1)-(1:9).

[0037] More preferably, the nucleating agent is a compound of an inorganic nucleating agent and an organic nucleating agent, and the mass ratio of the two is (8:2)-(6:4).

[0038] The function of the nucleating agent in the PPS composition of the present invention is to further refine the crystal grains after the molecular chain of the silicone-modified PPS resin is assisted. If this substance is not introduced, the product cannot achieve the effective toughening purpose, and the impact strength and elongation at break cannot reach the use standard. Under the above-preferred compounding of the nucleating agent, the organic nucleating agent can improve the dispersibility of the overall nucleating agent and promote nucleation by forming hydrogen bonds with the PPS resin, while the inorganic nucleating agent promotes nucleation as a heterogeneous nucleation point. The two nucleating agents can supplement sufficient crystal nuclei in the molten state of the resin and accelerate the crystallization rate, and the product can exhibit more excellent comprehensive performance.

[0039] More preferably, the particle size D50 of the inorganic nucleating agent is 0.1-3 μm.

[0040] The particle size D50 of the inorganic nucleating agent of the present invention can be directly detected by a laser particle size analyzer.

[0041] Preferably, the components of the PPS composition further include 0.1-2 parts of a processing aid;

[0042] More preferably, the processing aid includes at least one of an antioxidant, a lubricant, and a colorant.

[0043] More preferably, the components of the PPS composition further include at least one of 0.01-1 part of an antioxidant, 0.01-1 part of a lubricant, and 0.01-1 part of a colorant.

[0044] Based on the needs of the actual product, those skilled in the art can appropriately introduce some components commonly introduced in PPS composition products without affecting the product performance, such as antioxidants to improve the aging resistance of the product, lubricants to improve the processing performance of the product, and colorants to endow the product with various color systems, etc.

[0045] Preferably, in the PPS composition of the present invention, the mass content of the PPS resin is not less than 70 wt%.

[0046] Another object of the present invention is to provide a preparation method of the PPS composition, comprising the following steps:

[0047] After mixing each component evenly, melt-extrude and granulate in a screw extruder to obtain the PPS composition.

[0048] The preparation method of the PPS composition of the present invention has simple operation steps and can realize industrial-scale production.

[0049] Preferably, the temperature range of the screw extruder is set as: 150 - 280 °C, the screw speed is 300 - 400 r / min, and the screw length-diameter ratio is (38 - 42):1.

[0050] Another object of the present invention is to provide the application of the PPS composition in the preparation of electronic and electrical components.

[0051] Preferably, the electronic device is at least one of a connector buckle and a notebook fan.

[0052] The PPS composition of the present invention can achieve high toughness without introducing a toughening agent, specifically showing excellent impact strength and elongation at break. At the same time, the product has a high crystallization temperature, good processing performance, a short molding cycle, and also has sufficient tensile strength, and is very suitable for the preparation of electronic devices.

[0053] The beneficial effect of the present invention is that the present invention provides a PPS composition. In this product, a specific type of silicone is introduced into the PPS matrix for compounding. At the same time, under the action of a nucleating agent, the toughness and elongation at break of the PPS matrix are achieved without introducing a toughening agent, and the product can maintain a high tensile strength, a high crystallization temperature, and can be applied to the preparation of electronic devices operating at a relatively high working temperature. Detailed implementation mode

[0054] To better illustrate the objectives, technical solutions, and advantages of the present invention, the present invention will be further described below in conjunction with specific examples and comparative examples. The purpose is to understand the content of the present invention in detail, rather than to limit the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention. The experimental reagents and instruments involved in the implementation of the present invention are all common ordinary reagents and instruments unless otherwise specified.

[0055] Examples 1 - 21

[0056] An embodiment of the PPS composition and its preparation method according to the present invention, the composition components of the PPS composition are shown in Table 1.

[0057] The preparation method of the PPS composition includes the following steps:

[0058] After all components in the formula are mixed evenly by a high - speed mixer, they are fed into a twin - screw extruder from the main feeding port for melt - blending extrusion and pelletizing to obtain the PPS composition.

[0059] When the components are melt - blended and extruded, the temperature zones of the screw extruder are set as follows: zone 1 at 150 °C, zone 2 at 260 °C, zone 3 at 270 °C, zone 4 at 280 °C, zone 5 at 270 °C, zone 6 at 260 °C, zone 7 at 260 °C, zone 8 at 260 °C, zone 9 at 260 °C, zone 10 at 250 °C, the screw speed is 300 rpm, and the screw length - to - diameter ratio is 40:1.

[0060] Comparative Examples 1 - 10

[0061] The difference between each comparative example and the example lies only in the types and ratios of the components, as shown in Table 2.

[0062] Among the components of each example and comparative example,

[0063] The PPS resin 1 is PPS 3418 produced by Shin - Etsu, a linear polyphenylene sulfide resin, with a melt flow rate of 180 g / 10 min at 316 °C and 5 kg;

[0064] The PPS resin 2 is PPS1130C produced by Shin - Etsu, a linear polyphenylene sulfide resin, with a melt flow rate of 250 g / 10 min at 316 °C and 5 kg;

[0065] The PPS resin 3 is PPS 3450 produced by Shin - Etsu, a linear polyphenylene sulfide resin, with a melt flow rate of 500 g / 10 min at 316 °C and 5 kg;

[0066] The PPS resin 4 is PPS 3407 produced by Xinhecheng, a linear polyphenylene sulfide resin, and has a melt flow rate of 70 g / 10 min at 316° C. and 5 kg;

[0067] The PPS resin 5 is PPS21330CF produced by Xinhecheng, a non-linear polyphenylene sulfide resin, and has a melt flow rate of 250 g / 10 min at 316° C. and 5 kg;

[0068] The nucleating agent 1 is talcum powder produced by Aihaiyimi, HTP ultra5, with a particle size D50 of 0.65 μm;

[0069] The nucleating agent 2 is kaolin provided by Hua Zhongrong, 211E, with a particle size D50 of 2.82 μm;

[0070] The nucleating agent 3 is a thermotropic liquid crystal polymer as described in CN109777105B, with a melting point of 280°C, an m:n ratio of 3:1 in the molecular structure, and an aromatic polyester;

[0071] The nucleating agent 4 is a thermotropic liquid crystal polymer as described in CN109777105B, with a melting point of 320°C, an m:n ratio of 6:1 in the molecular structure, and an aromatic polyester;

[0072] The siloxane 1 is EF-6K produced by Shandong Dongyue Silicone Materials, and has the following molecular structure: a linear siloxane containing double-terminal epoxy groups, and a dynamic viscosity of 145 mPa*s at 25°C;

[0073]

[0074] Wherein R is an epoxy group;

[0075] The siloxane 2 is EF-15K produced by Shandong Dongyue Silicone Materials, has the same molecular structure as siloxane 1, is a linear siloxane containing double-terminal epoxy groups, and has a dynamic viscosity of 500 mPa*s at 25°C;

[0076] The siloxane 3 is EF-3.5K produced by Shandong Dongyue Silicone Materials, has the same molecular structure as siloxane 1, is a linear siloxane containing double-terminal epoxy groups, and has a dynamic viscosity of 100 mPa*s at 25°C;

[0077] The siloxane 4 is EF-20K produced by Shandong Dongyue Silicone Materials, has the same molecular structure as siloxane 1, is a linear siloxane containing double-terminal epoxy groups, and has a dynamic viscosity of 850 mPa*s at 25°C;

[0078] The siloxane 5 is AFS-81100 produced by Suzhou Qitian, a bis(3-aminopropyl)-terminated polydimethylsiloxane, a linear siloxane containing double-terminated amino groups, and has a dynamic viscosity of 196 mPa*s at 25°C;

[0079] The silicone 6 is dimethyl silicone oil 201-500 produced by Shandong Dongyue Organic Silicon Materials, a dimethyl silicone oil with no terminal epoxy groups or amino groups, and its kinematic viscosity at 25 °C is 480 mPa*s;

[0080] The silicone 7 is MP200 produced by Momentive, a branched silicone with terminal epoxy functional groups, and its kinematic viscosity at 25 °C is 35 mPa*s;

[0081] The toughening agent 1 is a terpolymer of ethylene-methyl acrylate-glycidyl methacrylate produced by Arkema, LOTADER AX8840; the mass fraction of the glycidyl methacrylate chain segment is 7%;

[0082] The toughening agent 2 is a copolymer of glycidyl methacrylate-ethylene octene produced by Jia Yirong, SOG-03, and the mass fraction of the glycidyl methacrylate chain segment is 3%;

[0083] Unless otherwise specified, the component raw materials used in each example and comparative example of the present invention are all commercially available raw materials, and the component raw materials used in each parallel experiment are of the same kind.

[0084] Table 1

[0085]

[0086]

[0087] Table 2

[0088]

[0089] In order to verify the performance of the PPS composition described in the present invention, the products prepared in each example and comparative example were subjected to the following performance tests, and the specific steps are as follows:

[0090] (1) Room temperature notchless impact strength test: Test according to the GB / T 1843:2008 standard, and the thickness of the specimen is 4 mm;

[0091] (2) Tensile strength test: Test according to the GB / T 1040:2006 standard, and the tensile rate is 10 mm / min;

[0092] (3) Elongation at break test: Test according to the GB / T 1040:2006 standard, and the tensile rate is 10 mm / min;

[0093] (4) Crystallization temperature test: Test according to the GB / T 13464:2008 standard.

[0094] The test results are shown in Tables 3 and 4.

[0095] Table 3

[0096]

[0097] Table 4

[0098]

[0099] As can be seen from Table 3 and Table 4, the PPS composition of the product described in the present invention has a relatively high notched impact strength, which can reach 45 kJ / m 2 and above (45 - 65 kJ / m 2 range), and the tensile strength can reach 74 or above (74 - 77 kJ / m 2Within a certain range), the elongation at break reaches more than 10% (within the range of 10 - 14%), and the crystallization temperature reaches more than 242°C (within the range of 242 - 244.2°C). In contrast, the products of Comparative Examples 9 and 10 are existing conventional toughener-modified products. Although the toughness properties of the products are comparable to those of the products of the examples of the present invention, the tensile strength of the products cannot be guaranteed, and the crystallization temperature is significantly reduced, greatly limiting the application fields of the products. In the products of the present invention, the key substances involved in the toughening modification of PPS resin are siloxane and nucleating agent. As shown in Comparative Examples 1 and 2, compared with Example 2, if one of them is missing, the improvement in the toughness of the product is not ideal, and the crystallization temperature of the product decreases to some extent, indicating that in the products of the present invention, the roles of siloxane and nucleating agent in the crystallization temperature are not only to maintain the basic level of the PPS composition, but also to improve it. From the products of Example 2, Example 4, Example 20 and Comparative Example 4, it can be seen that not any linear PPS resin composition can achieve ideal comprehensive performance after being modified with the siloxane and nucleating agent of the present invention. If the fluidity of the PPS resin itself is too large or too small, even after modification, the rigidity and toughness of the product cannot be balanced, and there is not much practical application significance. The non-linear PPS resin used in the product of Comparative Example 5 cannot react with the linear siloxane, so the toughness of this product does not meet the requirements, and thus it is similar in performance to the control product of Comparative Example 6 without the introduction of siloxane. On the other hand, from Comparative Examples 7 and 8, it can be seen that in the products of the present invention, not any kind of siloxane can achieve a similar modification path. Siloxanes without specific end groups or non-linear structures cannot match the product system of the present invention. From the comparison of the products of Example 2 and Examples 5 - 7, it can be seen that with the change in the viscosity of the siloxane, the performance of the product also changes to a certain extent. When the viscosity of the siloxane is maintained within the range of 145 - 500 Pa*s, the comprehensive performance of the product is better. At the same time, from Example 2, Examples 9 - 11 and Comparative Example 3, it can be seen that the addition amount of siloxane has a certain influence on the performance of the product. As the addition amount of siloxane increases, the reaction degree with the PPS resin is more thorough, and the degree of product modification improvement is higher. However, if too much is added, as shown in Comparative Example 3, it will lead to a decrease in the crystallization temperature and does not improve the toughness of the system. The types of nucleating agents selected in the products of Example 2 and Examples 12 - 19 are different. It can be seen that when an inorganic nucleating agent and an organic nucleating agent are compounded, and the mass ratio of the inorganic nucleating agent to the organic nucleating agent is (8:2) - (6:4), the grain refinement effect of the product is better, making the degree of product modification improvement higher than that in other ratios or when using a single nucleating agent.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A PPS composition, characterized in that, Comprising the following components in parts by weight: 95 - 99 parts of PPS resin, 0.5 - 2 parts of nucleating agent, 0.5 - 2 parts of silicone; The PPS resin is a linear polyphenylene sulfide resin, and its melt flow rate at 316 °C and 5 kg load is 70 - 250 g / 10 min; The silicone is a linear silicone containing terminal epoxy groups and / or terminal amino groups.

2. The PPS composition according to claim 1, characterized in that, The dynamic viscosity of the silicone at 25 °C is 100 - 900 Pa*s.

3. The PPS composition according to claim 1, wherein, The nucleating agent is at least one of an inorganic nucleating agent and an organic nucleating agent.

4. The PPS composition according to claim 3, wherein The inorganic nucleating agent is at least one of zinc oxide, boron nitride, talcum powder, kaolin, aluminum oxide, silicon dioxide, calcium oxide, titanium dioxide; the organic nucleating agent is a liquid crystal polymer.

5. The PPS composition according to claim 1, wherein The nucleating agent is a compound of an inorganic nucleating agent and an organic nucleating agent, and the mass ratio of the two is (1:9) - (9:1).

6. The preparation method of the PPS composition according to any one of claims 1 to 5, characterized in that, Comprising the following steps: After mixing the components evenly, melt - extrude and pelletize in a screw extruder to obtain the PPS composition.

7. The application of the PPS composition according to any one of claims 1 - 5 in the preparation of electronic devices.

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