A fast-spreading high-temperature-resistant fluorine-free anti-wicking agent, a preparation method and application thereof

Abstract

This invention discloses a fast-spreading, high-temperature resistant, fluorine-free antiwicking agent, its preparation method, and its applications. The antiwicking agent integrates fast-spreading, high-temperature resistant, and crosslinking capabilities through different side chains branched onto the polysiloxane backbone, rather than directly embedding them into the backbone. The polydimethylsiloxane backbone maintains flexibility, the polyether side chains enable rapid anchoring and spreading of polyester fibers, the phenyl side chains provide high-temperature stability, and residual Si-H groups or terminal hydroxyl groups of the polyether provide crosslinking anchoring. This invention's "three-side-chain synergistic" design effectively solves the three major problems of existing fluorine-free antiwicking agents: slow spreading, poor heat resistance, and insufficient durability.

Description

Technical Field

[0001] This invention belongs to the field of anti-wicking agent material preparation, specifically relating to a fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent, its preparation method, and its application. Background Technology

[0002] Polyester industrial yarn is a crucial raw material for industrial textiles, widely used in products such as tire cord, conveyor belts, light box advertising fabrics, tarpaulin materials, and airbags. In these applications, preventing moisture from penetrating the fiber bundles through capillary action (i.e., wicking) is a key indicator of product performance. Significant wicking can lead to interfacial delamination of composite materials, corrosion of metal components, and a decline in the mechanical properties of the material, severely impacting the lifespan and reliability of the final product.

[0003] Traditionally, achieving highly efficient antiwicking relies primarily on fluorinated compounds, such as fluorocarbon resins. These substances, with their extremely low surface energy, impart excellent water and oil repellency to fiber surfaces. However, perfluorinated and polyfluoroalkyl substances (PFAS) are facing increasingly stringent restrictions and phase-out globally due to their difficulty in degradation, easy bioaccumulation, and potential ecological risks. Against this backdrop, developing environmentally friendly, highly efficient, and fluorine-free antiwicking agents has become a critical technological bottleneck that the polyester industrial yarn industry chain urgently needs to overcome.

[0004] Currently, the technical solutions for fluorine-free antiwicking finishing of polyester industrial yarn mainly focus on the following two categories.

[0005] The first category consists of hydrophobic polyacrylate polymers, such as polymers prepared from long-chain alkyl monomers like octadecyl acrylate. The second category consists of modified organosilicon antiwicking agents, typically amino- or epoxy-modified polysiloxanes. These agents utilize their active groups to interact with the fiber surface and are compounded in spinning oils to form a hydrophobic film on the fiber surface, thereby replacing fluorinated chemicals.

[0006] However, the existing solutions mentioned above still have significant shortcomings in practical applications.

[0007] Firstly, the spreading speed is insufficient. Conventional silicone polymers or hydrophobic polyacrylates spread dynamically on the surface of polyester fibers at a relatively slow rate. On high-speed spinning production lines, it is difficult to form a uniform and complete film in a very short time, which can easily lead to problems such as fiber fuzz and breakage, thus restricting production efficiency.

[0008] Secondly, it has poor high-temperature resistance. The spinning process of polyester industrial yarn requires stretching and heat setting (180–250°C), and end applications such as tire vulcanization also involve high-temperature environments. Under such conditions, ordinary organosilicon segments may undergo oxidative cross-linking or thermal degradation under long-term high-temperature conditions, resulting in a decline in film performance.

[0009] Third, it has poor durability. The silicone film that adheres to the fiber surface by physical adsorption has weak bonding with the substrate and is prone to migration or detachment under high temperature, high humidity or mechanical friction conditions, making it difficult to provide long-lasting and stable anti-wicking protection.

[0010] Fourth, poor hand feel and processing adaptability. Long-chain alkyl acrylate polymers have limited compatibility with polyester fiber surfaces in some systems, easily forming discontinuous, island-like, non-uniform films. More importantly, these polymers often impart a noticeable waxy or sticky feel to the fibers rather than a smooth feel, severely affecting fiber bundleability and smoothness, leading to excessively high friction coefficients during high-speed spinning, resulting in fuzzing and breakage problems.

[0011] In summary, there is an urgent need for a fluorine-free antiwicking agent that simultaneously possesses rapid spreading ability, excellent high-temperature resistance, long-lasting adhesion, and a good hand feel. In particular, how to achieve the construction of a controllable cross-linking structure within the film layer to improve abrasion resistance and durability is a key issue that needs to be addressed in order to promote the green and high-performance development of polyester industrial yarn. Summary of the Invention

[0012] To address the problem that existing anti-wicking agents often fail to simultaneously possess rapid spreading ability, excellent high-temperature resistance, durable adhesion, and a pleasant feel, this invention provides a fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent, its preparation method, and its applications. This invention introduces the three functions of rapid spreading, high-temperature resistance, and crosslinkability into the polysiloxane backbone via side chains, rather than directly embedding them into the backbone. Specifically, by controlling the total addition number of ethylene oxide and propylene oxide in the polyether segments, the steric hindrance and segment flexibility of the side chains are synergistically controlled, thereby indirectly affecting the accessibility of residual Si-H groups and the density of crosslinking points. The polydimethylsiloxane backbone retains its flexibility, the polyether side chains impart rapid anchoring and spreading ability to polyester fibers, and the phenyl side chains enhance high-temperature stability. In some embodiments, unreacted Si-H groups are retained in the polymer or reactive groups such as hydroxyl groups are introduced, which can further improve the film durability. This "three-side-chain synergistic" design effectively solves the main shortcomings of existing fluorine-free anti-wicking agents in terms of spreading speed, high-temperature resistance, and durability.

[0013] This invention designs and synthesizes a polysiloxane-polyether-thermo-hydrophobic copolymer, which forms a good fit with the surface of polyester fibers. The hydrophilic / lipophilic segment ratio (EO / PO ratio) of the allyl-terminated polyether macromonomer exhibits a favorable match with the density of polar sites on the polyester fiber surface, and based on this, the optimal molecular design parameter range (EO / PO = 1.5:1-2:1, Mn = 1000-2000) is determined. By controlling the degree of polymerization of the EO / PO segments (x+y), the length of the polyether side chains is precisely controlled, thereby adjusting the steric hindrance and reaction accessibility of the molecular segments, and thus controlling the probability of Si-H / hydroxyl groups participating in the crosslinking reaction, achieving a controllable design of the crosslinking network density. Furthermore, this invention discovers that the chain length of the polyether side chains (characterized by the total addition number x+y of ethylene oxide and propylene oxide) not only affects the spreading properties of the material but also influences the reaction accessibility of residual Si-H groups by controlling the steric hindrance of the chain segments, significantly regulating the crosslinking behavior of the system. As x+y increases, the density of allyl end groups per unit mass decreases, thereby reducing the density of hydrosilylation grafting points and further affecting the density of the crosslinked network structure after film formation. This increases the film's flexibility but decreases its wear resistance. Conversely, decreasing x+y increases the crosslinking density and enhances the film's compactness. By adjusting x+y, the crosslinking density and the film's wear resistance and thermal stability can be synergistically controlled.

[0014] Furthermore, the introduction of phenyl or other large-volume aromatic / alicyclic groups can improve the thermal stability of the polymer. Their rigid structure helps to slow down the degradation of the Si-O backbone under high-temperature conditions, inhibiting its thermal oxidative crosslinking and cracking. Simultaneously, these hydrophobic groups enhance the overall heat resistance and hydrophobicity. In addition, this invention can introduce hydrolyzable crosslinking groups (e.g., ethoxy, hydroxyl) into the polymer molecule while retaining unreacted Si-H groups, allowing them to slowly hydrolyze and condense under film formation or high-temperature conditions, forming a three-dimensional crosslinked network structure on the fiber surface. Simultaneously, the residual Si-H groups in the polysiloxane backbone can undergo silanol condensation or further oxidation with the terminal hydroxyl groups of the polyether under platinum catalysis or hot / humid conditions to form Si–O–Si bonds, thereby constructing a three-dimensional crosslinked network structure. This structure can firmly "anchor" the polymer to the fiber surface, significantly improving the wear resistance and durability of the oil film and effectively reducing performance degradation caused by physical shedding. Meanwhile, the cross-linked structure can constrain the movement of polymer chains, keeping the molecular arrangement of the fiber surface film layer stable. During secondary heating or heat setting, the arrangement and aggregation state of the molecular chains are not easily changed, which helps to maintain the anti-wicking performance for a long time.

[0015] One of the technical solutions of this invention is to provide a fast-spreading, high-temperature resistant, and fluorine-free antiwicking agent. The antiwicking agent is a side-chain functionalized polysiloxane, with a main chain of polysiloxane and side chains including fast-spreading functional segments and high-temperature resistant hydrophobic functional segments. The high-temperature resistant hydrophobic functional segments are phenyl or cyclohexyl. The polysiloxane main chain retains 5–30 mol% of Si-H groups, and the polyether segments contain hydroxyl or methoxy groups at their ends, which can undergo a condensation reaction under heat treatment or catalytic conditions to form a Si–O–Si crosslinked structure.

[0016] The rapidly spreading functional segments are introduced through an organosilicon monomer containing a vinyl group at one end and a polyether group at the other end, and are connected by an addition reaction between the vinyl group and the silicon atoms on the polysiloxane backbone. The end of the polyether group can be a hydroxyl or a methoxy group. The high-temperature resistant hydrophobic functional segments are phenyl or cyclohexyl groups, connected by silicon atoms on the main chain. The polysiloxane main chain contains unreacted or partially unreacted Si-H groups and / or the polyether side chain ends contain crosslinkable groups (hydroxyl or methoxy).

[0017] Furthermore, the polyether segment is a poly(ethylene oxide)-propylene oxide copolymer (EO / PO segment).

[0018] Furthermore, the rapidly spreading functional segment can be represented as an allyl-terminated polyether CH2=CH-CH2-(EO). x -(PO) y -R, where R is a hydroxyl group (providing crosslinking reactivity) or an alkoxy group (providing inert end-capping), and the EO / PO ratio is 1.5:1~2:1. The number-average molecular weight of the polyether segments is preferably 1000~2000; where 10≤x+y≤45, and the crosslinking point density can be controlled by adjusting this value.

[0019] The residual Si-H bonds on the main chain or the hydroxyl groups at the ends of the polyether side chains can undergo cross-linking reactions on the fiber surface or under high temperature conditions to form a stable three-dimensional network film, thereby improving the durability of the antiwicking agent.

[0020] The second technical solution of the present invention is to provide a method for preparing the above-mentioned fast-spreading, high-temperature resistant, fluorine-free antiwicking agent, comprising the following steps: (1) Mix octamethylcyclotetrasiloxane (D4), tetramethylcyclotetrasiloxane (D4H), tetramethyltetraphenylcyclotetrasiloxane, hydrogen-containing end-capping agent and catalyst evenly, and react at 80-100℃ for 4-8 hours to obtain hydrogen-containing phenyl polysiloxane. (2) Neutralize the catalyst and filter to remove solid byproducts; (3) Add allyl polyether with an EO / PO ratio of 1.5:1 to 2:1, and carry out a hydrosilylation reaction at 80-120℃ for 2-4 hours until the C=C reaction is complete. Remove low-boiling substances by vacuum distillation to obtain the fast-spreading, high-temperature resistant, and fluorine-free antiwicking agent. The polyether segments in the allyl polyether help improve the interaction between the antiwicking agent and the surface of polyester fibers. At the same time, the siloxane backbone has low surface energy and good flexibility, which is beneficial to the spreading and film formation of the antiwicking agent on the fiber surface. During the subsequent heat treatment, the residual Si-H reacts with the terminal hydroxyl groups of the polyether to form a Si–O–Si crosslinked network structure.

[0021] Furthermore, the mass ratio of the octamethylcyclotetrasiloxane to the tetramethyltetraphenylcyclotetrasiloxane is (80-100):(8-18).

[0022] The third technical solution of the present invention provides another method for preparing a fast-spreading, high-temperature resistant, fluorine-free antiwicking agent, comprising the following steps: (1) Mix octamethylcyclotetrasiloxane (D4), tetramethylcyclotetrasiloxane (D4H), hydrogen-containing end-capping agent and catalyst evenly, and react at 80-100℃ for 4-8 hours to synthesize hydrogen-containing polysiloxane. (2) Neutralize the catalyst and filter to remove solid acid; (3) Add allyl polyether with an EO / PO molar ratio of 1.5:1~2:1 and a number average molecular weight (Mn) of 1000~2000, and carry out the first step of hydrosilylation reaction at 80-120℃ for 2-4 hours.

[0023] (4) Add styrene or allylbenzene to carry out a second hydrosilylation reaction for 2-4 hours; after the reaction, remove low-boiling substances by vacuum distillation to obtain the fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent. The molar ratio of styrene or allylbenzene to the remaining Si-H is changed to 0.6-1.0:1, preferably 0.8-1.0:1, and more preferably 0.9-1.0:1.

[0024] Further, the mass ratio of the octamethylcyclotetrasiloxane to styrene or allylbenzene is (100):(2-15).

[0025] Furthermore, the mass ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, and hydrogen-containing end-capping agent is (80-100):(5-20):(1-3); the allyl polyether has an equivalent of 1.0-1.2 times that of Si-H.

[0026] To improve the spreading performance of antiwicking agents on the surface of polyester fibers, this invention uses allyl-terminated polyether as a functional side chain, and optimizes its interfacial properties by adjusting the ratio of ethylene oxide (EO) units to propylene oxide (PO) units in the polyether chain segment.

[0027] Among them, the EO segment contains an ether oxygen structure, which can enhance the interaction between the polymer and the surface of polyester fibers, and is beneficial to improving the wetting and spreading ability of the material on the fiber surface; the PO segment has a certain degree of hydrophobicity, which helps to maintain the hydrophobic properties after film formation and reduce the water absorption tendency caused by the excessive hydrophilicity of the polyether segment.

[0028] Furthermore, the number-average molecular weight of the allyl polyether is preferably 1000–2000. Within this molecular weight range, the polymer's spreading properties, film-forming properties, and processing adaptability can be better balanced, thereby achieving a superior anti-wicking effect.

[0029] The fourth technical solution of the present invention is to provide the application of the above-mentioned fast-spreading, high-temperature resistant, fluorine-free antiwicking agent.

[0030] Specifically, it includes the following steps: (1) The fast-spreading, high-temperature resistant, fluorine-free antiwicking agent is mixed with emulsifier and water and then emulsified under high-speed shearing to obtain an emulsion with a solid content of 30%-50%. The graft copolymer of the present invention is used as the core antiwicking component, and the amount added to the spinning oil is generally 5%-20%. It needs to be used in combination with smoothing agents (such as polyol esters, mineral oil), antistatic agents (such as phosphate salts, quaternary ammonium salts), emulsifiers (such as fatty alcohol polyoxyethylene ethers), etc.

[0031] (2) Dilute the emulsion to 0.5%-2.0wt% as working solution, apply it to polyester industrial yarn by roller coating or spraying, dry it at 100-120℃, and then heat set it at 180-220℃ to complete cross-linking and curing.

[0032] The advantages of this invention are: (1) Excellent spreading performance: The fluorine-free antiwicking agent prepared by the present invention has a fast spreading speed on the surface of polyester fiber, and the dynamic spreading time can be controlled within 5 seconds, which is conducive to the rapid formation of a uniform film layer during high-speed spinning and improves processing adaptability.

[0033] (2) Good heat resistance stability: The antiwicking agent prepared by this invention can still maintain high hydrophobicity after high-temperature treatment, and the film layer does not show obvious stickiness, charring or other phenomena, which can meet the use requirements of high-temperature processing processes such as heat setting of polyester industrial yarn.

[0034] (3) Excellent anti-wicking durability: The polyester industrial yarn treated with the anti-wicking agent of the present invention has a low wicking height and can still maintain good anti-wicking performance after high temperature treatment and friction, showing good durability.

[0035] (4) Adjustable cross-linking network structure: By adjusting the length of polyether segments, the cross-linking density can be precisely controlled, so that the material can achieve a designable balance between wear resistance, flexibility and spreadability.

[0036] (5) Environmental friendliness: The preparation process of this invention does not contain any intentionally added fluorine-containing water-repellent components, which helps to reduce environmental risks and is in line with the development direction of green chemicals. Detailed Implementation

[0037] The following examples are provided to further illustrate the present invention and are intended to explain the invention, not to limit its scope. Unless otherwise specified, all figures are expressed in parts by weight and weight percentages.

[0038] Unless otherwise specified, the raw materials used in this invention are all conventional commercially available products; unless otherwise specified, the methods used in this invention are all conventional methods in the field.

[0039] In this invention, the ring-opening equilibrium polymerization catalyst can be trifluoromethanesulfonic acid, acid clay, sulfonic acid resin, or other acidic catalysts capable of catalyzing the equilibrium polymerization reaction of organosilicon.

[0040] In this invention, the wicking height is determined as follows: the fiber bundle is suspended vertically, its lower end is immersed in deionized water, and after standing at (25±2)℃ for 16 hours, the height of the liquid rising along the fiber bundle direction is measured. The lower the wicking height, the better the anti-wicking performance.

[0041] In this invention, the dynamic spreading time is determined as follows: At (25±2)℃, 1 μL of oil emulsion is dropped onto the surface of a polyester film. Using a video contact angle meter, the time required for the droplet contact angle to drop below 10° is recorded as the dynamic spreading time. A shorter dynamic spreading time indicates better spreading performance.

[0042] The embodiments of the present invention will be further described below with reference to several examples.

[0043] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0044] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0045] Example 1 (1) Add 100 parts by mass of octamethylcyclotetrasiloxane (D4), 8 parts by mass of tetramethylcyclotetrasiloxane (D4H), 10 parts by mass of tetramethyltetraphenylcyclotetrasiloxane, 2 parts by mass of end-capping agent hexamethyldisiloxane, and 100 parts by mass of toluene to a reactor equipped with a condenser, a stirrer, and a nitrogen inlet pipe, and stir to dissolve.

[0046] (2) Purge nitrogen to replace the air in the reactor and turn on the heating to 60°C.

[0047] (3) Slowly add 0.5 parts by mass of trifluoromethanesulfonic acid catalyst, and after the addition is complete, react at 80°C for 6 hours.

[0048] (4) After the reaction is complete, cool down to 40°C, add sodium bicarbonate to neutralize to neutral, and filter to remove solid salt.

[0049] (5) Remove toluene and unreacted monomers by vacuum distillation to obtain hydrogen-containing / phenyl-containing polysiloxane (colorless to pale yellow transparent liquid).

[0050] Step 2: Hydrosilylation Grafting (1) Add 100 parts by mass of the product from the previous step to the reactor, add 50 parts by mass of isopropanol to dilute, and heat to 90°C under nitrogen protection.

[0051] (2) Add 0.1 parts by mass of chloroplatinic acid catalyst and stir until homogeneous.

[0052] (3) Slowly add 35 parts by mass of allyl polyether (Mn=1500, EO / PO=1.8:1, terminal -OCH3, total addition number of ethylene oxide and propylene oxide (x+y)=29) diluted to 50% concentration with isopropanol, and add it over about 1 hour.

[0053] (4) After reacting at 100°C for 3 hours, samples were taken and infrared spectroscopy was used to detect the characteristic absorption peak of C=C (1600-1680 cm⁻¹). -1 The reaction ends when the characteristic absorption peak of C=C basically disappears and the Si-H peak (2100 cm⁻¹) weakens significantly.

[0054] (5) Remove isopropanol and low-boiling substances by vacuum distillation to obtain a pale yellow transparent viscous liquid.

[0055] (6) Dilute to 0.5% to obtain working solution, apply to polyester industrial yarn by roller coating, dry at 100°C, and form a stable hydrophobic film layer during subsequent heat setting at 180°C.

[0056] The resulting pale yellow, transparent, viscous liquid has a solid content ≥98%, a viscosity of 1650 mPa·s (25°C), a dynamic spreading time of 4.8s, an initial water contact angle of 136°, a contact angle of 129° after heat treatment at 250°C / 2h, an initial wicking height of 1.9cm, a wicking height of 2.2cm after heat treatment, and a wicking height of 2.4cm after 50 cycles of friction.

[0057] The total number of additions (x+y) of ethylene oxide and propylene oxide in the polyether segment not only affects the spreading performance, but also has a significant impact on the spatial accessibility of the crosslinking reaction.

[0058] As (x+y) increases, the length of the polyether side chain increases and the flexibility of the molecular chain segment is enhanced. However, the steric hindrance effect reduces the effective collision probability of Si-H groups or terminal hydroxyl groups, resulting in a decrease in the crosslinking network density. When (x+y) decreases, the side chains become too short, leading to enhanced intermolecular interactions and increased crosslinking density, but this may cause film embrittlement or insufficient spreading.

[0059] Therefore, by adjusting (x+y), the density of the crosslinked network can be designed in an adjustable manner, thereby achieving synergistic optimization of anti-wicking performance and wear resistance.

[0060] Example 2 (1) Add 100 parts by mass of octamethylcyclotetrasiloxane (D4), 5 parts by mass of tetramethylcyclotetrasiloxane (D4H), 18 parts by mass of tetramethyltetraphenylcyclotetrasiloxane, 1.5 parts by mass of end-capping agent hexamethyldisiloxane, and 100 parts by mass of toluene to a reactor equipped with a condenser, a stirrer, and a nitrogen inlet pipe, and stir to dissolve.

[0061] (2) Purge nitrogen to replace the air in the reactor and turn on the heating to 60°C.

[0062] (3) Slowly add 0.5 parts by mass of trifluoromethanesulfonic acid catalyst, and after the addition is complete, react at 80°C for 8 hours.

[0063] (4) After the reaction is complete, cool down to 40°C, add sodium bicarbonate to neutralize to neutral, and filter to remove solid salt.

[0064] (5) Remove toluene and unreacted monomers by vacuum distillation to obtain hydrogen-containing / phenyl-containing polysiloxane (colorless to pale yellow transparent liquid).

[0065] Step 2: Hydrosilylation Grafting (1) Add 100 parts by mass of the product from the previous step to the reactor, add 50 parts by mass of isopropanol to dilute, and heat to 90°C under nitrogen protection.

[0066] (2) Add 0.08 parts by weight of chloroplatinic acid catalyst and stir until homogeneous.

[0067] (3) Slowly add 25 parts by mass of allyl polyether (Mn=1200, EO / PO=2:1, terminal -OCH3, total addition number of ethylene oxide and propylene oxide (x+y)=23) diluted to 50% concentration with isopropanol (corresponding to the medium chain length control region), and add it over about 1 hour.

[0068] (4) After reacting at 100°C for 3 hours, samples were taken and infrared spectroscopy was used to detect the characteristic absorption peak of C=C (1600-1680 cm⁻¹). -1 The reaction ends when the characteristic absorption peak of C=C basically disappears and the Si-H peak (2100 cm⁻¹) weakens significantly.

[0069] (5) Remove isopropanol and low-boiling substances by vacuum distillation to obtain a pale yellow transparent viscous liquid.

[0070] (6) Dilute to 2% to obtain working solution, apply to polyester industrial yarn by roller coating, dry at 100°C, and complete cross-linking and curing in subsequent heat setting at 180°C. The resulting pale yellow, transparent, viscous liquid had a solid content ≥98%, a viscosity of 2100 mPa·s (25°C), a dynamic spreading time of 4.9 s, an initial water contact angle of 143°, a contact angle of 137° after heat treatment at 250°C / 2h, an initial wicking height of 1.3 cm, a wicking height of 1.6 cm after heat treatment, and a wicking height of 1.8 cm after 50 cycles of friction. Compared to Example 1, the heat resistance and hydrophobic properties of the material improved with increasing phenyl unit content. The spreading time decreased slightly but remained significantly higher than that of the prior art.

[0071] Example 3 (1) Add 100 parts by mass of octamethylcyclotetrasiloxane (D4), 20 parts by mass of tetramethylcyclotetrasiloxane (D4H), 8 parts by mass of tetramethyltetraphenylcyclotetrasiloxane, 2.5 parts by mass of end-capping agent hexamethyldisiloxane, and 100 parts by mass of toluene to a reactor equipped with a condenser, a stirrer, and a nitrogen inlet pipe, and stir to dissolve.

[0072] (2) Purge nitrogen to replace the air in the reactor and turn on the heating to 60°C.

[0073] (3) Slowly add 0.5 parts by mass of trifluoromethanesulfonic acid catalyst, and after the addition is complete, react at 80°C for 6 hours.

[0074] (4) After the reaction is complete, cool down to 40°C, add sodium bicarbonate to neutralize to neutral, and filter to remove solid salt.

[0075] (5) Remove toluene and unreacted monomers by vacuum distillation to obtain hydrogen-containing / phenyl-containing polysiloxane (colorless to pale yellow transparent liquid).

[0076] Step 2: Hydrosilylation Grafting (1) Add 100 parts by mass of the product from the previous step to the reactor, add 60 parts by mass of isopropanol to dilute, and heat to 90°C under nitrogen protection.

[0077] (2) Add 0.15 parts by weight of chloroplatinic acid catalyst and stir until homogeneous.

[0078] (3) Slowly add 55 parts by mass of allyl polyether (Mn=1000, EO / PO=1.5:1, terminal -OH, total addition number of ethylene oxide and propylene oxide (x+y)=19) diluted to 50% concentration with isopropanol, and add it over about 1 hour.

[0079] (4) After reacting at 110°C for 4 hours, samples were taken and infrared spectroscopy was used to detect the characteristic absorption peak of C=C (1600-1680 cm⁻¹). -1 The reaction ends when the characteristic absorption peak of C=C basically disappears and the Si-H peak (2100 cm⁻¹) weakens significantly.

[0080] (5) Remove isopropanol and low-boiling substances by vacuum distillation to obtain a pale yellow transparent viscous liquid.

[0081] (6) Dilute to 0.5% to obtain working solution, apply to polyester industrial yarn by roller coating, dry at 120°C, and complete cross-linking and curing in subsequent heat setting at 220°C.

[0082] The resulting pale yellow, transparent, viscous liquid has a solid content of ≥98%, a viscosity of 1350 mPa·s (25°C), a dynamic spreading time of 2.9s, an initial water contact angle of 131°, a contact angle of 127° after heat treatment at 250°C / 2h, an initial wicking height of 2.3cm, a wicking height of 2.5cm after heat treatment, and a wicking height of 2cm after 50 rubs. It still maintains good anti-wicking performance after the friction test.

[0083] Example 4 (1) Add 80 parts by mass of octamethylcyclotetrasiloxane (D4), 5 parts by mass of tetramethylcyclotetrasiloxane (D4H), 12 parts by mass of tetramethyltetraphenylcyclotetrasiloxane, 2 parts by mass of end-capping agent hexamethyldisiloxane, and 100 parts by mass of toluene to a reactor equipped with a condenser, a stirrer, and a nitrogen inlet pipe, and stir to dissolve.

[0084] (2) Purge nitrogen to replace the air in the reactor and turn on the heating to 60°C.

[0085] (3) Slowly add 0.5 parts by mass of trifluoromethanesulfonic acid catalyst, and after the addition is complete, react at 80°C for 6 hours.

[0086] (4) After the reaction is complete, cool down to 40°C, add sodium bicarbonate to neutralize to neutral, and filter to remove solid salt.

[0087] (5) Remove toluene and unreacted monomers by vacuum distillation to obtain hydrogen-containing / phenyl-containing polysiloxane (colorless to pale yellow transparent liquid).

[0088] Step 2: Hydrosilylation Grafting (1) Add 100 parts by mass of the product from the previous step to the reactor, add 50 parts by mass of isopropanol to dilute, and heat to 90°C under nitrogen protection.

[0089] (2) Add 0.12 parts by weight of chloroplatinic acid catalyst and stir until homogeneous.

[0090] (3) Slowly add 45 parts by mass of allyl polyether (Mn=1500, EO / PO=1.8:1, terminal -OH, total addition number of ethylene oxide and propylene oxide (x+y)=29) diluted to 50% concentration with isopropanol, and add it over about 1 hour.

[0091] (4) After reacting at 95°C for 3 hours, samples were taken and infrared spectroscopy was used to detect the characteristic absorption peak of C=C (1600-1680 cm⁻¹). -1 The reaction ends when the characteristic absorption peak of C=C basically disappears and the Si-H peak (2100 cm⁻¹) weakens significantly.

[0092] (5) Remove isopropanol and low-boiling substances under reduced pressure to obtain a pale yellow, transparent, viscous liquid.

[0093] The resulting pale yellow, transparent, viscous liquid had a viscosity of 1900 mPa·s (25°C), a dynamic spreading time of 4.2 s, an initial water contact angle of 138°, a contact angle of 134° after heat treatment at 250°C for 2 h, an initial wicking height of 1.7 cm, a wicking height of 1.8 cm after heat treatment, and a wicking height of 1.9 cm after 50 cycles of friction. The terminal hydroxyl groups may enhance the interaction between the polymer and the fiber surface, thus maintaining good anti-wicking properties after heat treatment and friction tests.

[0094] Example 5 (1) Add 100 parts by mass of octamethylcyclotetrasiloxane (D4), 7 parts by mass of tetramethylcyclotetrasiloxane (D4H), 10 parts by mass of tetramethyltetraphenylcyclotetrasiloxane, 4 parts by mass of end-capping agent hexamethyldisiloxane, and 100 parts by mass of toluene to a reactor equipped with a condenser, a stirrer, and a nitrogen inlet pipe, and stir to dissolve.

[0095] (2) Purge nitrogen to replace the air in the reactor and turn on the heating to 60°C.

[0096] (3) Slowly add 0.5 parts by mass of trifluoromethanesulfonic acid catalyst, and after the addition is complete, react at 90°C for 5 hours.

[0097] (4) After the reaction is complete, cool down to 40°C, add sodium bicarbonate to neutralize to neutral, and filter to remove solid salt.

[0098] (5) Remove toluene and unreacted monomers by vacuum distillation to obtain hydrogen-containing / phenyl-containing polysiloxane (colorless to pale yellow transparent liquid).

[0099] Step 2: Hydrosilylation Grafting (1) Add 100 parts by mass of the product from the previous step to the reactor, add 50 parts by mass of isopropanol to dilute, and heat to 90°C under nitrogen protection.

[0100] (2) Add 0.1 parts by mass of chloroplatinic acid catalyst and stir until homogeneous.

[0101] (3) Slowly add 30 parts by mass of allyl polyether (Mn=1800, EO / PO=1.7:1, terminal -OCH3, total addition number of ethylene oxide and propylene oxide (x+y)=35) diluted to 50% concentration with isopropanol, and add it over about 1 hour.

[0102] (4) After reacting at 100°C for 3 hours, samples were taken and infrared spectroscopy was used to detect the characteristic absorption peak of C=C (1600-1680 cm⁻¹). -1 The reaction ends when the characteristic absorption peak of C=C basically disappears and the Si-H peak (2100 cm⁻¹) weakens significantly.

[0103] (5) Remove isopropanol and low-boiling substances by vacuum distillation to obtain a pale yellow transparent viscous liquid.

[0104] (6) Dilute to 0.5% to obtain working solution, apply to polyester industrial yarn by roller coating, dry at 120°C, and complete cross-linking and curing in subsequent heat setting at 220°C.

[0105] The resulting pale yellow, transparent, viscous liquid has a viscosity of 850 mPa·s (25°C), a dynamic spreading time of 5s, an initial water contact angle of 137°, a contact angle of 131° after heat treatment at 250°C for 2h, an initial wicking height of 1.8cm, a wicking height of 2.0cm after heat treatment, and a wicking height of 2.1cm after 50 cycles of friction. This embodiment is easy to emulsify or spray and has good overall performance.

[0106] Example 6 Post-grafted phenyl olefins (two-step method) (1) After the second step of the hydrosilylation in Example 1 is completed, the hydrogen-containing polysiloxane containing polyether side chains is added to the reactor and isopropanol is added to dilute to a concentration of 50%. The temperature is raised to 90°C under nitrogen protection.

[0107] (2) Add 0.1 parts by weight of chloroplatinic acid catalyst and stir until homogeneous.

[0108] (3) Slowly add 10 parts by mass of styrene diluted to 50% concentration with isopropanol, and add it over about 1 hour to make the molar ratio of phenyl olefin to the remaining Si-H in the main chain close to 1:1.

[0109] (4) After reacting at 100℃ for 4 hours, samples were taken and infrared spectroscopy was used to detect the characteristic absorption peak of C=C (1600-1680 cm⁻¹). -1 The reaction ends when the characteristic absorption peak of C=C basically disappears and the Si-H peak (2100 cm⁻¹) weakens significantly.

[0110] (5) Remove isopropanol and low-boiling substances by vacuum distillation to obtain a pale yellow transparent viscous liquid.

[0111] (6) Dilute to 0.5% to prepare a working solution, apply it to polyester industrial yarn by roller coating, dry at 100°C, and form a hydrophobic film layer in subsequent heat setting at 180°C.

[0112] Results and performance: Dynamic spreading time: 3.6 s; Initial water contact angle: 135°; Contact angle after heat treatment at 250℃ / 2h: 131°; Initial wicking height: 1.5 cm; Wicking height after heat treatment: 1.7 cm; Wicking height after 50 cycles of friction: 1.8 cm; Grafting of phenyl side chains helps to improve the high-temperature stability and hydrophobic properties of the polymer, while maintaining a fast spreading speed.

[0113] The excessively long chain segments lead to a significant increase in steric hindrance, a decrease in Si-H accessibility, a reduction in hydrosilylation conversion rate, and a significant decrease in film crosslinking density, resulting in decreased hydrophobicity and reduced wear resistance.

[0114] Example 7 The difference from Example 1 is that the allyl-terminated polyether used has an EO / PO ratio of 2:1, an end of -OH, and x+y=45.

[0115] The resulting pale yellow, transparent, viscous liquid has a solid content of ≥98%, a viscosity of approximately 1700 mPa·s (25°C), a dynamic spreading time of 4.0 s, an initial water contact angle of 137°, a contact angle of 133° after heat treatment at 250°C for 2 hours, an initial wicking height of 1.6 cm, a wicking height of 1.8 cm after heat treatment, and a wicking height of 1.9 cm after 50 cycles of friction.

[0116] Compared with Example 1, due to the increase of the total addition number (x+y) of EO / PO side chains to 45, the degree of molecular chain extension is improved, the density of effective reaction sites in the system decreases, resulting in a relatively loose cross-linking network, but it can still maintain good hydrophobicity and heat resistance stability. The spreading performance is slightly reduced but still within an acceptable range.

[0117] Example 8 The difference from Example 1 is that the allyl-terminated polyether used has an EO / PO ratio of 2:1, an end of -OH, and x+y=10.

[0118] The resulting pale yellow, transparent, viscous liquid has a solid content of ≥98%, a viscosity of approximately 1200 mPa·s (25°C), a dynamic spreading time of 2.6 s, an initial water contact angle of 132°, a contact angle of 126° after heat treatment at 250°C for 2 hours, an initial wicking height of 2.4 cm, a wicking height of 2.7 cm after heat treatment, and a wicking height of 2.6 cm after 50 cycles of friction.

[0119] Compared with Example 1, the total addition number (x+y) of EO / PO side chains is reduced to 10, the molecular chain is significantly shortened, and the polyether side chain spreading speed is significantly accelerated. However, the interfacial anchoring ability and crosslinking density are insufficient, resulting in a decrease in heat resistance and friction resistance.

[0120] The experimental results show that as x+y increases from 10 to 70, the density of allyl end groups per unit mass in the system gradually decreases, and the density of hydrosilylation grafting points decreases accordingly. This leads to a gradual shift in the crosslinked network structure from dense to loose, resulting in a decrease in the heat resistance and wear resistance of the film, while the spreading performance shows a pattern of first improving and then decreasing.

[0121] Comparative Example 1 The difference from Example 1 is that the EO / PO ratio in the allyl-terminated polyether used is 4:1. The results showed that the initial wicking height was >5 cm. This is because the molecules are too hydrophilic and their own water absorption may increase the hydrophilicity of the material, thereby reducing the anti-wicking performance.

[0122] Comparative Example 2 The difference from Example 1 lies in the EO / PO ratio used in the allyl-terminated polyether, which was 0.2:1. The results showed a spreading time >20 seconds, due to insufficient polarity of the polyether segments, leading to decreased spreading performance. When the EO / PO molar ratio is controlled within the range of 1.5:1 to 2:1, the resulting antiwicking agent balances spreading and hydrophobic properties, exhibiting superior overall performance. Excessive EO content increases polymer hydrophilicity, potentially reducing antiwicking performance; conversely, insufficient EO content may weaken its spreading ability on the fiber surface.

[0123] Comparative Example 3 This comparative example uses a commercially available amino-modified polydimethylsiloxane emulsion with a solid content of 30%, a viscosity of 2000 mPa·s, a dynamic spreading time >25 s, an initial water contact angle of 125°, and a contact angle of 98° after heat treatment at 250°C for 2 hours. After heat treatment, it becomes noticeably sticky and yellows. The initial wicking height is 4.2 cm, and after heat treatment at 250°C, the wicking height is >7.0 cm. After 50 cycles of friction, the wicking height is 6.3 cm. This anti-wicking agent has a slow spreading speed and is unsuitable for high-speed spinning. It has poor high-temperature resistance, and its performance is severely degraded after heat treatment. Furthermore, the amino group itself is hydrophilic, weakening the anti-wicking effect, resulting in insufficient durability and a significant decrease in performance after friction.

[0124] Comparative Example 4 This comparative example prepares a long-chain hydrophobic polyacrylate emulsion.

[0125] (1) Mix 80 parts by weight of octadecyl acrylate, 15 parts by weight of methyl methacrylate and 5 parts by weight of acrylic acid evenly to form the oil phase.

[0126] (2) Dissolve 2 parts by mass of sodium dodecyl sulfate (SDS) and 2 parts by mass of nonylphenol polyoxyethylene ether (NP-10) in 200 parts by mass of deionized water as the aqueous phase.

[0127] (3) The oil phase was slowly added to the water phase under high-speed shear (10000 rpm) and pre-emulsified for 30 minutes to obtain a milky white pre-emulsion.

[0128] (4) Transfer the pre-emulsion to the reactor and heat it to 75°C under nitrogen protection.

[0129] (5) Add 0.5 parts by weight of ammonium persulfate aqueous solution (dissolved in 10 parts of water), and the addition will be completed in about 1 hour.

[0130] (6) Keep the reaction at 75°C for 5 hours.

[0131] (7) Cool to room temperature, adjust pH to 7.0 with ammonia, filter to obtain milky white emulsion, and let stand to form slight stratification.

[0132] The milky white emulsion has a solid content of approximately 35%, with a particle size of 250-280 nm. Its dynamic spreading time is >15 seconds, indicating slow spreading and indistinct droplet edges. The initial water contact angle is 118°, decreasing to 95° after heat treatment at 250°C for 2 hours. The film exhibits significant yellowing, brittleness, and powdering. The initial wicking height is 5.5 cm, increasing to >8.0 cm after 250°C heat treatment, and decreasing to 7.2 cm after 50 cycles of friction. This anti-wicking agent suffers from emulsification difficulties, large emulsion particle size, and poor stability; insufficient hydrophobicity (contact angle <120°), resulting in unsatisfactory anti-wicking effects; extremely poor high-temperature resistance, with significant yellowing and embrittlement observed after treatment at 250°C. It also exhibits weak fiber bonding and poor durability.

[0133] Comparative Example 5 The difference from Example 1 is that hydrosilylation grafting is not performed.

[0134] The resulting colorless, transparent, viscous liquid had a solid content ≥98%, a viscosity of 580 mPa·s, a dynamic spreading time >30s (extremely slow, almost no spreading), an initial water contact angle of 105°, which decreased to 95° after heat treatment at 250°C for 2 hours, an initial wicking height of 4.5 cm, a wicking height of 5.8 cm after heat treatment at 250°C, and a wicking height of 5.2 cm after 50 cycles of friction. This indicates that polyether side-linking plays a crucial role in improving the spreading and anti-wicking properties of the material.

[0135] Comparative Example 6 The difference from Example 1 is that the total number of additions (x+y) between ethylene oxide and propylene oxide is 70, the molecular chain length is significantly increased, and the double bond density per unit mass is reduced.

[0136] Experimental results show that the dynamic spreading time of the comparative sample was significantly prolonged (>10 s), indicating a decreasing spreading rate; the initial water contact angle was approximately 128°, lower than that of Example 1; after heat treatment at 250℃ for 2 h, the contact angle decreased to approximately 120°, indicating a weakening of heat resistance stability; the initial wicking height was approximately 3.0 cm, which increased to approximately 3.6 cm after heat treatment, and further increased to approximately 4.0 cm after 50 cycles of friction, indicating a significant decrease in wicking durability.

[0137] Analysis suggests that the longer polyether segments lead to an increase in molecular weight, which reduces the density of allyl groups per unit mass that can participate in hydrosilylation reactions. At the same time, the increased steric hindrance results in a decrease in grafting efficiency. In addition, excessively long hydrophilic / flexible segments are prone to local rearrangement or migration under high temperature conditions, which reduces the stability of the film layer and weakens the overall anti-wicking and wear resistance.

[0138] The above embodiments detail the structure, features, and effects of the present invention. The above descriptions are merely preferred embodiments of the present invention. Any changes made in accordance with the concept of the present invention, or equivalent embodiments modified to have equivalent variations, shall still fall within the scope of protection of the present invention if they do not exceed the scope covered by the specification.

Claims

1. A fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent, characterized in that, The anti-wicking agent is a side-chain functionalized polysiloxane, with a main chain of polysiloxane and side chains including fast-spreading functional segments and high-temperature resistant hydrophobic functional segments. The fast-spreading functional segments are obtained by grafting organosilicon monomers with an alkenyl group at one end and a polyether segment at the other end onto the polysiloxane main chain via a hydrosilylation reaction. The polyether segment ends with a hydroxyl or methoxy group. The high-temperature resistant hydrophobic functional segments are phenyl or cyclohexyl groups.

2. The fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent according to claim 1, characterized in that, The main chain of the antiwicking agent contains unreacted or partially unreacted Si-H groups.

3. The fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent according to claim 1, characterized in that, The rapidly spreading functional segment is an allyl-terminated polyether; the polyether segment is a polyethylene oxide-propylene oxide copolymer, specifically: CH2=CH-CH2-(EO) x -(PO) y -R, Where R is a hydroxyl or methoxy group, and the EO / PO ratio is 1.5:1 to 2:1; where 10 ≤ x + y ≤ 45.

4. A method for preparing the fast-spreading, high-temperature resistant, fluorine-free antiwicking agent as described in claim 1, characterized in that, It includes the following steps: (1) Mix octamethylcyclotetrasiloxane (D4), tetramethylcyclotetrasiloxane (D4H), tetramethyltetraphenylcyclotetrasiloxane, hydrogen-containing end-capping agent and catalyst evenly, and react at 80-100 °C for 4-8 hours to synthesize hydrogen-containing phenyl polysiloxane. (2) Neutralize the catalyst and filter to remove solid impurities; (3) Add allyl polyether with an EO / PO ratio of 1.5:1~2:1 and react at 80-120℃ for 2-4 hours to carry out hydrosilylation until the C=C reaction is complete. Remove low-boiling substances by vacuum distillation to obtain a fast-spreading, high-temperature resistant, fluorine-free antiwicking agent.

5. The method according to claim 4, characterized in that, The mass ratio of octamethylcyclotetrasiloxane to tetramethyltetraphenylcyclotetrasiloxane is (80-100):(8-18).

6. A method for preparing the fast-spreading, high-temperature resistant, fluorine-free antiwicking agent as described in claim 1, characterized in that, It includes the following steps: (1) Mix octamethylcyclotetrasiloxane (D4), tetramethylcyclotetrasiloxane (D4H), hydrogen-containing end-capping agent and catalyst evenly, and react at 80-100℃ for 4-8 hours to obtain hydrogen-containing polysiloxane. (2) Neutralize the catalyst and filter to remove solid impurities; (3) Add allyl polyether with an EO / PO ratio of 1.5:1 to 2:1 and react at 80-120°C for 2-4 hours; (4) Add styrene or allylbenzene and react at 80-120℃ for 2-4 hours; (5) Low-boiling substances are removed by vacuum distillation to obtain a fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent.

7. The method according to claim 6, characterized in that, The mass ratio of the octamethylcyclotetrasiloxane to styrene or allylbenzene is (100):(5-15).

8. The method according to any one of claims 4-7, characterized in that, The mass ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, and hydrogen-containing end-capping agent is (80-100):(5-20):(1-3); the allyl polyether is 1.0-1.2 times equivalent to Si-H.

9. The application of a fast-spreading, high-temperature resistant, fluorine-free antiwicking agent as described in any one of claims 1-3 in the antiwicking finishing of polyester industrial yarn.

10. The application according to claim 9, characterized in that, It includes the following steps: (1) Mix and emulsify the fast-spreading, high-temperature resistant, fluorine-free anti-wicking agent with emulsifier and water to obtain an emulsion with a solid content of 30%-50%; (2) Dilute the emulsion to 0.5%-2.0wt% as working solution, apply it to polyester industrial yarn by roller coating or spraying, dry it at 100-120℃, and then heat set it at 180-220℃.