Optical cable secondary coating material based on thermoplastic elastomer and preparation method

Abstract

The invention discloses an optical cable secondary coating material based on a thermoplastic elastomer and a preparation method thereof, the optical cable secondary coating material comprises the following components by weight: 65-75 parts of a TPEE base material, 10-15 parts of a special low temperature resistant plasticizer, and 9-13 parts of an auxiliary agent; wherein the freezing point of the special low-temperature-resistant plasticizer is less than or equal to-60 DEG C; the volatilization decrement at the temperature of 25 DEG C for 24 hours is less than or equal to 0.5 wt%; the solubility parameter difference delta delta with the TPEE base material is less than or equal to 1.0 (J / cm) 1 / 2; the special low temperature resistant plasticizer is dioctyl oxalate or dioctyl sebacate or diisononyl oxalate; the invention further discloses a preparation method of the optical cable secondary coating material based on the thermoplastic elastomer. The low-temperature flexibility of the TPEE base material can be improved on the premise that the mechanical strength is not sacrificed; meanwhile, through the flexible structure of plasticizer molecules, the elasticity and flexibility of the material in a low-temperature environment are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of communication materials, and particularly relates to a secondary coating material for optical cables based on thermoplastic elastomers and a preparation method thereof. BACKGROUND

[0002] With the development of the 5G market, the development of the optical communication industry is also increasingly rapid, and different optical cable product structures and demands emerge in endlessly, especially the most core optical fiber protection material of the optical cable, the performance of the loose sleeve of the optical cable also has multiple requirements, especially in extremely cold regions, the ordinary loose sleeve is prone to pre-cooling brittle cracking or rupture.

[0003] The material used in cold regions must be selected to adapt to the cold environment, and the yield strength of the material increases sharply at low temperature, and is equal to the breaking strength at a certain temperature. The traditional secondary coating material of the optical cable is prone to hardening and embrittlement in a low-temperature environment, which leads to the decrease of the flexibility and mechanical strength of the optical cable, and affects the stability of signal transmission and the service life of the optical cable. Therefore, it is of great significance to develop an optical cable coating material capable of maintaining good performance in a low-temperature environment. SUMMARY

[0004] The application aims to overcome the deficiencies of the prior art and provide a secondary coating material for optical cables based on thermoplastic elastomers and a preparation method thereof, which has excellent low-temperature resistance and good mechanical strength, chemical corrosion resistance and environmental stability.

[0005] To achieve the above-mentioned purpose, the technical scheme adopted by the application is as follows: a secondary coating material for optical cables based on thermoplastic elastomers, which comprises, by weight: 65-75 parts of TPEE base material, 10-15 parts of special low-temperature resistant plasticizer, and 9-13 parts of auxiliary agent; wherein the freezing point of the special low-temperature resistant plasticizer is ≤-60℃, the volatile reduction amount at 25℃ for 24 hours is ≤0.5 wt%, and the solubility parameter difference |Δδ| with the TPEE base material is ≤1.0 (J / cm³)¹ / ².

[0006] Preferably, the special low-temperature resistant plasticizer is dioctyl adipate or dioctyl sebacate or diisononyl adipate.

[0007] Preferably, the auxiliary agent comprises a high-efficiency anti-aging agent, a thermal stabilizer and a functional auxiliary agent.

[0008] Preferably, the high-efficiency anti-aging agent is 4010NA, 4020 or BMC.

[0009] Preferably, the thermal stabilizer is zinc benzoate or an organic tin stannic acid salt.

[0010] Preferably, the functional additives include one or both of a flame retardant and an antistatic agent.

[0011] A preparation method of a thermoplastic elastomer-based secondary coating material for optical cables, comprising the following steps:

[0012] S1, uniformly mixing a TPEE base material and a special low-temperature-resistant plasticizer in a high-temperature mixer, to form a mixture after ensuring that the two are fully compatible;

[0013] S2, sequentially adding high-efficiency anti-aging agents, thermal stabilizers and functional additives into the mixture, and continuing to mix until completely uniform;

[0014] S3, melt-extruding the mixture in step S2 to form a uniform secondary coating material for optical cables;

[0015] S4, obtaining a product with stable performance after cooling, solidifying and post-processing the material in S3.

[0016] Preferably, the temperature of the high temperature in step S1 is between 100° and 180°, and the mixing time is 15-35 minutes.

[0017] Preferably, in step 3, the extrusion temperature is controlled at 170-190℃, the screw rotation speed is 280-320 rpm, and the extrusion pressure is 12-18 MPa.

[0018] Preferably, the cooling water temperature in step S4 is 18-22℃.

[0019] Thanks to the use of the above technical solutions, the present application has the following advantages compared with the prior art:

[0020] The thermoplastic elastomer-based secondary coating material for optical cables of the present application, wherein the special low-temperature-resistant plasticizer used is one of dioctyl adipate or dioctyl sebacate or diisononyl adipate, and these plasticizers have polar groups such as ether bonds and ester bonds, which can enhance the compatibility of the plasticizer with the TPEE base material, thereby improving the low-temperature softness of the TPEE base material without sacrificing the mechanical strength; at the same time, through the flexible structure of the plasticizer molecules, longer alkyl chains or branched structures can be introduced, increasing the flexibility of the molecular chain, thereby reducing the glass transition temperature (Tg) and improving the elasticity and flexibility of the TPEE base material in a low-temperature environment. BRIEF DESCRIPTION OF DRAWINGS The technical solutions of the present application will be further described below in conjunction with the drawings: Figure 1 The flowchart of the preparation method of the thermoplastic elastomer-based secondary coating material for optical cables in an embodiment of the present application; DETAILED DESCRIPTION

[0021] In order to make the person skilled in the art better understand the scheme of the present application, the technical scheme in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the protection scope of the present application.

[0022] The application provides a thermoplastic elastomer-based secondary coating material for optical cables and a preparation method thereof, to solve the problem that the secondary coating material for optical cables in the prior art is prone to hardening and embrittlement in a low-temperature environment, resulting in a decrease in the flexibility and mechanical strength of the optical cable and affecting the stability of signal transmission and the service life of the optical cable.

[0023] The application provides a thermoplastic elastomer-based secondary coating material for optical cables, which comprises 65-75 parts of TPEE base material, 10-15 parts of special low-temperature-resistant plasticizer and 9-13 parts of auxiliary agent by weight. / The solidification point of the special low-temperature-resistant plasticizer is ≤-60℃, the volatile reduction amount at 25℃ for 24 hours is ≤0.5 wt%, and the solubility parameter difference |Δδ| with the TPEE base material is ≤1.0 (J / cm³)¹

[0024] Specifically, the special low-temperature-resistant plasticizer is dioctyl adipate, dioctyl sebacate or diisononyl adipate, but is not limited to the three kinds.

[0025] The auxiliary agent comprises a high-efficiency anti-aging agent, a thermal stabilizer and a functional auxiliary agent.

[0026] Further, the high-efficiency anti-aging agent is 4010NA, 4020 or BMC.

[0027] Further, the thermal stabilizer is zinc benzoate or an organic tin alkane acid salt.

[0028] Further, the functional auxiliary agent comprises one or both of a flame retardant and an antistatic agent.

[0029] The thermoplastic elastomer-based optical cable secondary coating material of the present application uses a special low-temperature-resistant plasticizer, namely, one of dioctyl adipate or dioctyl succinate or diisononyl adipate, which has a polar group, such as an ether bond or an ester bond, so as to enhance the compatibility of the plasticizer with the TPEE base material, thereby improving the low-temperature softness of the TPEE base material without sacrificing the mechanical strength; meanwhile, the flexible structure of the plasticizer molecule itself can introduce a longer alkyl chain or a branched structure, thereby increasing the flexibility of the molecular chain, reducing the glass transition temperature (Tg), and improving the elasticity and flexibility of the TPEE base material in a low-temperature environment.

[0030] The present application also provides a preparation method of the thermoplastic elastomer-based optical cable secondary coating material, which is described below by means of multiple method embodiments.

[0031] Embodiment 1

[0032] The formula in the present embodiment is as follows (calculated by weight parts): TPEE base material: 70 parts, special low-temperature-resistant plasticizer (dioctyl adipate): 12 parts, high-efficiency anti-aging agent (4010NA): 3 parts, thermal stabilizer (zinc benzoate): 4 parts, and functional additives (flame retardant): 3 parts.

[0033] A preparation method of a thermoplastic elastomer-based optical cable secondary coating material, the steps of which are as follows:

[0034] S1, mix the TPEE base material and the dioctyl adipate in a high-temperature mixer, control the temperature at 120°C, and mix for 30 minutes to ensure that the two are fully compatible and form a uniform mixture.

[0035] S2, sequentially add the high-efficiency anti-aging agent (4010NA), the thermal stabilizer (zinc benzoate), and the flame retardant, and continue to mix in the high-temperature mixer, keep the temperature at 100°C, and mix for 20 minutes until completely uniform.

[0036] S3, melt-extrude the mixed material in a twin-screw extruder, control the extrusion temperature at 180°C, the screw rotation speed at 300 rpm, and the extrusion pressure at 15 MPa, to form a uniform optical cable secondary coating material.

[0037] S4, cool the extruded material through a water cooling device, control the cooling water temperature at 20°C, and the cooling time at 3 minutes, and then perform solidification treatment, control the solidification temperature at 60°C, and the solidification time at 2 hours, to ensure the stability of the material performance.

[0038] The prepared material has the following properties:

[0039] 1. Low temperature resistance: at -70℃, flexibility retention rate is 85%, mechanical strength retention rate is 90%; at -40℃, flexibility retention rate is 92%, mechanical strength retention rate is 93%.

[0040] 2. Tensile strength: 28 MPa, elongation at break 450%.

[0041] 3. UV aging resistance: after 1000 hours of UV irradiation, tensile strength retention rate is 82%, elongation at break retention rate is 78%.

[0042] Example 2

[0043] The formulation in this embodiment is as follows (calculated by weight parts): TPEE base material: 75 parts, special low-temperature plasticizer (dicaprylyl carbonate): 10 parts, high-efficiency anti-aging agent (4020): 4 parts, thermal stabilizer (organic tin stannate): 3 parts, and functional additives (antistatic agent): 2 parts.

[0044] A preparation method of a secondary coating material for optical cables based on thermoplastic elastomers, the steps of which are as follows:

[0045] S1, mix the TPEE base material and dicaprylyl carbonate in a high-temperature mixer, control the temperature at 110℃, and mix for 25 minutes to ensure that the two are fully compatible and form a uniform mixture.

[0046] S2, add high-efficiency anti-aging agent (4020), thermal stabilizer (organic tin stannate), and antistatic agent in sequence, continue to mix in the high-temperature mixer, keep the temperature at 90℃, and mix for 15 minutes until completely uniform.

[0047] S3, melt-extrude the mixed material in a twin-screw extruder, control the extrusion temperature at 170℃, the screw speed at 280 rpm, and the extrusion pressure at 12 MPa, to form a uniform secondary coating material for optical cables.

[0048] S4, cool the extruded material through a water cooling device, the cooling water temperature is 18℃, the cooling time is 2 minutes, then perform solidification treatment, the solidification temperature is 55℃, and the solidification time is 1.5 hours, to ensure the stability of the material properties.

[0049] The properties of the prepared material are as follows:

[0050] 1. Low temperature resistance: at -70℃, flexibility retention rate is 82%, mechanical strength retention rate is 88%; at -40℃, flexibility retention rate is 90%, mechanical strength retention rate is 92%.

[0051] 2. Tensile strength: 27 MPa, elongation at break 420%.

[0052] 3. UV aging resistance: after 1000 hours of UV irradiation, the tensile strength retention rate is 80%, and the elongation at break retention rate is 76%.

[0053] Example 3

[0054] The formulation in this embodiment is as follows (calculated by weight parts): TPEE base material: 65 parts, special low-temperature plasticizer (diisononyl adipate): 15 parts, high-efficiency anti-aging agent (BCMC): 5 parts, thermal stabilizer (zinc benzoate): 5 parts, and functional additives (flame retardant and antistatic agent each 1 part): 2 parts.

[0055] A preparation method of a thermoplastic elastomer-based optical cable secondary coating material, the steps of which are as follows:

[0056] S1, mix the TPEE base material and diisononyl adipate in a high-temperature mixer, control the temperature at 130°C, and mix for 35 minutes to ensure that the two are fully compatible and form a uniform mixture.

[0057] S2, add high-efficiency anti-aging agent (BCMC), thermal stabilizer (zinc benzoate), and functional additives (flame retardant and antistatic agent) in sequence, continue to mix in the high-temperature mixer, maintain the temperature at 110°C, and mix for 25 minutes until completely uniform.

[0058] S3, melt-extrude the mixed material in a twin-screw extruder, control the extrusion temperature at 190°C, the screw speed at 320 rpm, and the extrusion pressure at 18 MPa to form a uniform optical cable secondary coating material.

[0059] S4, cool the extruded material through a water cooling device, control the cooling water temperature at 22°C, and cool for 4 minutes, then perform solidification treatment, control the solidification temperature at 65°C, and solidify for 2.5 hours to ensure the stability of the material properties.

[0060] The prepared material properties are as follows:

[0061] 1. Low-temperature resistance: at -70°C, the flexibility retention rate is 88%, and the mechanical strength retention rate is 92%; at -40°C, the flexibility retention rate is 95%, and the mechanical strength retention rate is 94%.

[0062] 2. Tensile strength: 29 MPa, elongation at break 480%.

[0063] 3. Anti-UV aging performance: After 1000 hours of UV irradiation, the tensile strength retention rate is 84%, and the elongation at break retention rate is 80%.

[0064] Through the comparison of the above three examples, it can be seen that:

[0065] 1. The effect of plasticizer type on performance: Diisononyl adipate (Example 3) performs best in low temperature resistance, with both flexibility retention and mechanical strength retention higher than the other two plasticizers.

[0066] 2. The effect of anti-aging agent type on performance: BCMCA (Example 3) performs slightly better than 4010NA and 4020 in anti-UV aging performance.

[0067] 3. The effect of functional additives: The material with the addition of flame retardant and antistatic agent (Example 3) performs better in comprehensive performance, meeting the needs of more application scenarios.

[0068] In addition, in the above three examples:

[0069] Examples TPEE / wt% Plasticizer type and amount / wt% -70 °C flexibility retention -70 °C strength retention Description 2 75 DOA 10 83% 88% Cost-oriented formulation 1 70 DOA 12 87% 92% Balanced recommendation 3 65 DINCH 15 92% 95% Extremely cold high-end formulation

[0070] The results of the low temperature resistance test of the optical cable coating material are as follows:

[0071] Temperature Flexibility retention Mechanical strength retention -70℃ Optical cable covering material: 80-90% Optical cable covering material: 85-95% -70℃ Prior art: 70-80% Prior art: 75-85% -40℃ Optical cable covering material: 90-95% Optical cable covering material: 90-95% -40℃ Prior art: 85-90% Prior art: 85-90%

[0072] The results of the tensile strength test of the optical cable coating material are as follows:

[0073] Tensile strength Breaking elongation rate Optical cable covering material 25-30 MPa 400%~500% Prior art 20-25 MPa 300%~400%

[0074] The results of the chemical corrosion resistance test of the optical cable coating material are as follows:

[0075] Tensile strength retention Breaking elongation rate retention Immersion in acidic medium for 720 hours Optical cable covering material: 80-90% Optical cable covering material: 85-95% Immersion in acidic medium for 720 hours Prior art: 70-80% Prior art: 75-85% Immersion in basic medium for 720 hours Optical cable covering material: 90-95% Optical cable covering material: 90-95% Immersion in basic medium for 720 hours Prior art: 85-90% Prior art: 85-90%

[0076] In addition, after being placed in a salt spray environment for 1000 hours, the optical cable coating material did not show obvious corrosion phenomena, and there were no cracks, peeling, and other abnormal conditions on the surface. However, the existing technology generally starts to show slight corrosion phenomena around 800 hours.

[0077] The results of the anti-UV aging performance test of the optical cable coating material are as follows:

[0078] Tensile strength retention Breaking elongation rate retention 1000 hours of UV radiation Optical cable covering material: 80-85% Optical cable covering material: 75-80% 1000 hours of UV radiation Prior art: 75-80% Prior art: 70-75%

[0079] The results of the mechanical strength test of the optical cable coating material are as follows:

[0080] In the tensile test, the tensile strength of the optical cable coating material can reach 1200-1500 N (the existing technology is generally 1000-1200 N); in the compression test, the compression strength of the optical cable coating material can reach 800-1000 N / cm2 (the existing technology is generally 700-800 N / cm2); in the bending test, the bending radius of the optical cable coating material can be less than or equal to 10 mm (the existing technology is generally about 15 mm), and the bending frequency can reach more than 10,000 times (the existing technology is generally about 8,000 times), thereby showing that the material has excellent mechanical strength and durability.

[0081] In summary, the optical cable secondary coating material based on thermoplastic elastomer has the characteristics of low temperature resistance and high strength, and is suitable for optical communication lines in extremely cold areas.

[0082] The above-described and above-mentioned examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A secondary coating material for optical cables based on thermoplastic elastomers, characterized in that, The product comprises, by weight, 65-75 parts of TPEE base material, 10-15 parts of a special low-temperature resistant plasticizer, and 9-13 parts of auxiliary additives; wherein the special low-temperature resistant plasticizer has a freezing point ≤ -60℃; a volatilization loss ≤ 0.5 wt% after 24 hours at 25℃; and a solubility parameter difference |Δδ| between the plasticizer and the TPEE base material ≤ 1.0 (J / cm³)¹ / ².

2. The optical cable secondary coating material based on thermoplastic elastomer as described in claim 1, characterized in that: The special low-temperature resistant plasticizer is dioctyl oxalate, dioctyl sebate, or diisononyl oxalate.

3. The optical cable secondary coating material based on thermoplastic elastomer as described in claim 1, characterized in that: The auxiliary agents include high-performance anti-aging agents, heat stabilizers, and functional additives.

4. The optical cable secondary coating material based on thermoplastic elastomer as described in claim 1, characterized in that: The high-performance anti-aging agents are 4010NA, 4020, and BCMC.

5. The optical cable secondary coating material based on thermoplastic elastomer as described in claim 1, characterized in that: The heat stabilizer is zinc benzoate or organotin alkylate.

6. The optical cable secondary coating material based on thermoplastic elastomer as described in claim 1, characterized in that: The functional additives include one or both of flame retardants and antistatic agents.

7. A method for preparing a secondary coating material for optical cables based on thermoplastic elastomers, characterized in that, Includes the following steps: S1. Mix the TPEE base material and the special low-temperature resistant plasticizer evenly in a high-temperature mixer to ensure that the two are fully compatible and form a mixture. S2. Gradually add the high-performance anti-aging agent, heat stabilizer and functional additives to the mixture in sequence, and continue mixing until completely homogeneous; S3. The mixture in step S2 is melt-extruded to form a uniform secondary coating material for optical cables; S4. After cooling, curing and post-processing the material in step S3, a product with stable performance is obtained.

8. The method for preparing the secondary coating material for optical cables based on thermoplastic elastomers as described in claim 7, characterized in that: In step S1, the high temperature is between 100° and 180°, and the mixing time is 15 min to 35 min.

9. The method for preparing the secondary coating material for optical cables based on thermoplastic elastomers as described in claim 7, characterized in that: In step 3, the extrusion temperature is controlled at 170℃-190℃, the screw speed is 280-320 rpm, and the extrusion pressure is 12-18 MPa.

10. The method for preparing the secondary coating material for optical cables based on thermoplastic elastomers as described in claim 7, characterized in that: The cooling water temperature in step S4 is between 18℃ and 22℃.

Images