Siloxane-based polymer material with specific polymerization degree and preparation method thereof

Abstract

The invention relates to the technical field of polymer materials, and discloses a siloxane-based polymer material with a specific polymerization degree, which is composed of the following components: 20-30 parts of a siloxane-based polymer material, 15-25 parts of polysulfide rubber, 10-20 parts of epoxy resin, 5-10 parts of a curing agent, 10-20 parts of a solvent, and 1-5 parts of an auxiliary agent. Wherein the polymerization degree of a Q-type related part corresponding to the siloxane-based polymer material is 1.3-2.7, the polymerization degree of a D-type related part corresponding to the siloxane-based polymer material is 1.0-1.9, and the polymerization degree of a T-type related part corresponding to the siloxane-based polymer material is 1.1-2.7. According to the siloxane-based polymer material with the specific polymerization degree and the preparation method, the polymerization degrees of Q-type, D-type and T-type related parts of the siloxane-based polymer material are respectively controlled in narrow ranges of 1.3-2.7, 1.0-1.9 and 1.1-2.7; the problem of batch difference (for example, the tensile strength deviation is reduced from more than or equal to 15% to a controllable range) caused by large fluctuation of the polymerization degree (Q type 3.0-5.0, D type 2.0-4.0 and T type 2.5-4.5) of a traditional material is solved, the performance consistency of the material is ensured, and the requirements of high-end scenes such as precision equipment protection and the like can be met.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a siloxane polymer material with a specific degree of polymerization and its preparation method. Background Technology

[0002] In the field of coatings and polymer materials, polysulfide epoxy materials are widely used in anti-corrosion and sealing applications because they combine the flexibility of polysulfide rubber with the adhesiveness of epoxy resin. However, the performance of existing polysulfide epoxy materials is limited by core components and preparation processes, resulting in many technical shortcomings that make it difficult to meet the needs of high-end applications.

[0003] From the perspective of material properties, traditional polysulfide epoxy materials have insufficient precision in controlling the degree of polymerization. The degree of polymerization of the Q-type, D-type, and T-type components of its core polymer components fluctuates significantly (typically 3.0-5.0 for the Q-type component, 2.0-4.0 for the D-type component, and 2.5-4.5 for the T-type component), resulting in significant performance differences between batches of materials. For example, materials produced with the same formula can have tensile strength deviations of more than 15%, making them unsuitable for use in precision equipment protection scenarios with stringent requirements for performance stability. At the same time, residual moisture and impurities in the material can further exacerbate performance fluctuations, affecting the uniformity and durability of the coating.

[0004] In terms of preparation process, existing methods have problems such as lack of raw material pretreatment and unreasonable feeding methods. If the siloxane polymer material in the raw material is not dried, it will introduce moisture, which will reduce the compatibility with epoxy resin and cause coating blistering. If the solvent is not dehydrated, it is easy to cause the curing agent to react prematurely, shortening the material's pot life. In addition, most processes adopt a one-time feeding method, and the siloxane polymer material is prone to form agglomerates when mixed with epoxy resin. It is necessary to extend the stirring time to achieve uniform dispersion, which not only reduces production efficiency but may also lead to material degradation due to excessive stirring.

[0005] Storage stability is also a prominent issue for existing materials. Traditional polysulfide epoxy materials are greatly affected by temperature and humidity during storage, and are prone to premature curing or delamination under high temperature and high humidity conditions. Data shows that the viscosity of conventional materials stored at 30°C and 70% relative humidity for one month will increase by more than 30%, directly affecting construction performance. Moreover, most storage containers do not consider the need for light protection, and materials exposed to light for a long time are prone to oxidation, leading to performance degradation.

[0006] Therefore, it is necessary to propose a siloxane polymer material with a specific degree of polymerization and a preparation method to solve the problems mentioned above. Summary of the Invention

[0007] (a) Technical problems to be solved

[0008] To address the shortcomings of existing technologies, this invention provides a siloxane alkyl polymer material with a specific degree of polymerization and its preparation method. This material possesses advantages such as strong performance stability and efficient preparation process, solving the problem of significant batch-to-batch performance differences (tensile strength deviation can reach more than 15%) caused by large fluctuations in the degree of polymerization and unstable composition of traditional polysulfide epoxy materials. This technical solution significantly reduces performance fluctuations by precisely controlling the degree of polymerization and clearly defining the raw material ratio, thus meeting the needs of scenarios with high requirements for performance stability, such as the protection of precision equipment.

[0009] (II) Technical Solution

[0010] To achieve the aforementioned goals of high performance stability and efficient preparation process, this invention provides the following technical solution: a siloxane-alkyl polymer material with a specific degree of polymerization, comprising the following components: 20-30 parts of siloxane-alkyl polymer material, 15-25 parts of polysulfide rubber, 10-20 parts of epoxy resin, 5-10 parts of curing agent, 10-20 parts of solvent, and 1-5 parts of additives; wherein the degree of polymerization of the siloxane-alkyl polymer material corresponding to the Q-type related part is 1.3-2.7, the degree of polymerization of the D-type related part is 1.0-1.9, and the degree of polymerization of the T-type related part is 1.1-2.7.

[0011] Preferably, the curing agent is an amine curing agent, the solvent is xylene, and the additive is a plasticizer.

[0012] Preferably, the polysulfide rubber is liquid polysulfide rubber, and the epoxy resin is bisphenol A type epoxy resin.

[0013] A method for preparing a siloxane polymer material with a specific degree of polymerization includes the following steps:

[0014] Step 1: Weigh out the siloxane polymer material, polysulfide rubber, epoxy resin, curing agent, solvent, and additives according to the specified proportions, and set aside.

[0015] Step 2: Add epoxy resin to the mixing equipment, turn on the mixer, and stir at a speed of 200-300 rpm. Add solvent and stir for 5-10 minutes.

[0016] Step 3: Add the siloxane polymer material and polysulfide rubber to the mixing equipment in sequence, and continue mixing for 10-15 minutes;

[0017] Step 4: Add curing agent and additives, stir for 20-30 minutes until evenly mixed;

[0018] Step 5: Filter the mixed material with a mesh size of 100-200 to obtain the siloxane polymer material with a specific degree of polymerization.

[0019] Preferably, the siloxane polymer material in step one needs to be vacuum dried at 60-80°C for 2-3 hours before weighing, and then placed in a desiccator to cool to room temperature.

[0020] Preferably, the solvent added in step two needs to be dehydrated by molecular sieve, the molecular sieve is 4A molecular sieve, and the treatment time is 24-48 hours.

[0021] Preferably, in step three, the siloxane polymer material is added in two parts. The first part adds 60%-70% of the total amount, and the remaining amount is added after stirring for 5 minutes.

[0022] Preferably, in step four, the curing agent is added by dripping at a rate of 1-2 drops / second, and stirring is continued for 15-20 minutes after the dripping is completed.

[0023] Preferably, the material filtered in step five needs to be stored in a sealed container, which is a brown glass bottle, at a storage temperature of 15-25℃ and a relative humidity of ≤60%.

[0024] (III) Beneficial Effects

[0025] Compared with the prior art, the present invention provides a siloxane polymer material with a specific degree of polymerization and a method for its preparation, which has the following beneficial effects:

[0026] 1. This siloxane polymer material with a specific degree of polymerization and its preparation method solve the batch variation problem caused by the large fluctuation of the degree of polymerization of traditional materials (Q type 3.0-5.0, D type 2.0-4.0, T type 2.5-4.5) by controlling the degree of polymerization of the relevant parts of the siloxane polymer material within a narrow range of 1.3-2.7, 1.0-1.9, and 1.1-2.7, respectively). (For example, the tensile strength deviation is reduced from ≥15% to a controllable range). This ensures the consistency of material performance and can meet the needs of high-end scenarios such as the protection of precision equipment.

[0027] 2. This invention relates to a siloxane-alkyl polymer material with a specific degree of polymerization and its preparation method. The material exhibits significant improvements in several key properties: a purer appearance (no particles, transparent), improved viscosity stability (the fluctuation range at 25°C narrows from 40-120 cP to 50-90 cP); extended pot life (from 5-6 hours to ≥7 hours); improved curing efficiency (curing time at 25°C shortens from 24-30 hours to 18-24 hours); enhanced mechanical properties (tensile strength increases from 2.5-3.5 MPa to 3.5-4.5 MPa, and elongation at break increases from 150-200% to 200-300%); and improved salt spray resistance (extended from 300-400 hours to ≥450 hours).

[0028] 3. This siloxane polymer material with a specific degree of polymerization and its preparation method solve the problems of coating blistering and premature reaction of curing agent caused by water in raw materials in traditional processes by pretreatment steps such as vacuum drying of siloxane materials (60-80℃) and dehydration of solvent molecular sieves (24-48 hours); the batch feeding and curing agent dripping (1-2 drops / second) mixing method avoids agglomeration and improves mixing uniformity; the clear storage conditions (15-25℃, relative humidity ≤60%, sealed brown glass bottle) solve the problems of premature curing and delamination of existing materials and extend storage stability.

[0029] 4. The siloxane polymer material with a specific degree of polymerization and its preparation method have stable and controllable material properties, reducing the risk of performance fluctuations during construction; the shortened curing time and extended service life improve construction flexibility; and the improved salt spray resistance and mechanical properties expand its application scenarios in harsh environments such as high humidity and strong corrosion (e.g., marine engineering and chemical equipment corrosion protection). Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the siloxane-alkyl polymer material with a specific degree of polymerization and its preparation method according to the present invention. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1

[0033] This invention relates to a siloxane alkyl polymer material with a specific degree of polymerization and its preparation method, comprising the following:

[0034] I. Raw Material Preparation

[0035] Siloxane-based polymer materials: Q-type related part degree of polymerization 1.5, D-type related part degree of polymerization 1.2, T-type related part degree of polymerization 1.3;

[0036] Polysulfide rubber: Liquid polysulfide rubber;

[0037] Epoxy resin: Bisphenol A type epoxy resin;

[0038] Curing agent: Amine curing agent;

[0039] Solvent: Xylene;

[0040] Additives: Plasticizers.

[0041] II. Raw Material Pretreatment

[0042] Pretreatment of siloxane polymer materials: Place them in a vacuum drying oven, set the temperature to 60℃ and the vacuum degree to 0.07MPa, and dry for 3 hours. After drying, place them in a desiccator to cool to room temperature.

[0043] Solvent dehydration: Add 4A molecular sieve to xylene, treat for 24 hours, then filter for later use.

[0044] III. Material Preparation

[0045] Weigh the raw materials: 20 parts of siloxane polymer material, 15 parts of liquid polysulfide rubber, 10 parts of bisphenol A epoxy resin, 5 parts of amine curing agent, 10 parts of dehydrated xylene, and 1 part of plasticizer.

[0046] Add epoxy resin to the mixing tank and stir at 200 rpm. Add xylene and stir for 10 minutes.

[0047] The siloxane polymer material is added in two batches: first, add 60% (12 parts), stir for 5 minutes, then add the remaining 40% (8 parts), then add the polysulfide rubber, and continue stirring for 15 minutes.

[0048] Add the curing agent dropwise (1 drop / second), then add the plasticizer and stir for 30 minutes until the mixture is homogeneous.

[0049] The target material was obtained by filtering with a 100-mesh filter cloth.

[0050] IV. Storage

[0051] Seal the material in brown glass bottles and store it in an environment with 15°C and 50% relative humidity.

[0052] Example 2

[0053] This invention relates to a siloxane alkyl polymer material with a specific degree of polymerization and its preparation method, comprising the following:

[0054] I. Raw Material Preparation

[0055] Siloxane-based polymer materials: Q-type related part degree of polymerization 2.0, D-type related part degree of polymerization 1.5, T-type related part degree of polymerization 2.0;

[0056] Polysulfide rubber: Liquid polysulfide rubber;

[0057] Epoxy resin: Bisphenol A type epoxy resin;

[0058] Curing agent: Amine curing agent;

[0059] Solvent: Xylene;

[0060] Additives: Plasticizers.

[0061] II. Raw Material Pretreatment

[0062] Pretreatment of siloxane polymer materials: vacuum drying oven temperature 70℃, vacuum degree 0.08MPa, drying for 2.5 hours, and then cooling to room temperature.

[0063] Solvent dehydration: Xylene was treated with 4A molecular sieve for 36 hours and then filtered.

[0064] III. Material Preparation

[0065] Weigh the raw materials: 25 parts of siloxane polymer material, 20 parts of liquid polysulfide rubber, 15 parts of bisphenol A epoxy resin, 8 parts of amine curing agent, 15 parts of dehydrated xylene, and 3 parts of plasticizer.

[0066] Add epoxy resin to the mixing tank and stir at 250 rpm. Add xylene and stir for 7 minutes.

[0067] The siloxane polymer material was added in two batches: first, 65% (16.25 parts) was added and stirred for 5 minutes, then the remaining 35% (8.75 parts) was added, followed by polysulfide rubber and stirring for another 12 minutes.

[0068] Add curing agent (1.5 drops / second), add plasticizer and stir for 25 minutes until homogeneous.

[0069] The target material was obtained by filtering with a 150-mesh filter cloth.

[0070] IV. Storage

[0071] Seal in brown glass bottles and store at 20°C and 55% relative humidity.

[0072] Example 3

[0073] This invention relates to a siloxane alkyl polymer material with a specific degree of polymerization and its preparation method, comprising the following:

[0074] I. Raw Material Preparation

[0075] Siloxane-based polymer materials: Q-type related part degree of polymerization 2.7, D-type related part degree of polymerization 1.9, T-type related part degree of polymerization 2.7;

[0076] Polysulfide rubber: Liquid polysulfide rubber;

[0077] Epoxy resin: Bisphenol A type epoxy resin;

[0078] Curing agent: Amine curing agent;

[0079] Solvent: Xylene;

[0080] Additives: Plasticizers.

[0081] II. Raw Material Pretreatment

[0082] Pretreatment of siloxane polymer materials: vacuum drying oven temperature 80℃, vacuum degree 0.09MPa, dry for 2 hours, and cool to room temperature.

[0083] Solvent dehydration: Xylene was treated with 4A molecular sieve for 48 hours and then filtered.

[0084] III. Material Preparation

[0085] Weigh the raw materials: 30 parts of siloxane polymer material, 25 parts of liquid polysulfide rubber, 20 parts of bisphenol A epoxy resin, 10 parts of amine curing agent, 20 parts of dehydrated xylene, and 5 parts of plasticizer.

[0086] Add epoxy resin to the mixing tank and stir at 300 rpm. Add xylene and stir for 5 minutes.

[0087] The siloxane polymer material is added in two stages: first, add 70% (21 parts), stir for 5 minutes, then add the remaining 30% (9 parts), add polysulfide rubber and continue stirring for 10 minutes.

[0088] Add curing agent (2 drops / second), then add plasticizer and stir for 20 minutes until homogeneous.

[0089] The target material was obtained by filtering with a 200-mesh filter cloth.

[0090] IV. Storage

[0091] Seal in brown glass bottles and store at 25°C and 60% relative humidity.

[0092] The experiment was repeated three times for Example 2, and the test results are as follows: tensile strength 3.8±0.1MPa, 3.9±0.1MPa, 4.0±0.1MPa (relative standard deviation ≤2.6%); viscosity 75±2cP (relative standard deviation ≤2.7%), proving that the technical solution of the present invention can be stably repeated.

[0093] Example 4

[0094] Performance testing standards and methods

[0095] 1. Method for determining the degree of polymerization

[0096] The determination of the degree of polymerization of the relevant parts of the Q-type, D-type, and T-type siloxane polymer materials was based on gel permeation chromatography (GPC), with tetrahydrofuran as the mobile phase, polystyrene as the standard, a test temperature of 30℃, a flow rate of 1.0 mL / min, and the degree of polymerization was calculated from the molecular weight distribution.

[0097] 2. Key Performance Testing Standards

[0098] Tensile strength and elongation at break: According to GB / T1040.1-2018 "Determination of tensile properties of plastics - Part 1: General", the test rate is 50 mm / min, and the specimen type is type I dumbbell shape.

[0099] Salt spray resistance: According to GB / T1771-2007 "Determination of resistance to neutral salt spray of paints and varnishes", the salt spray chamber temperature is 35℃, the sodium chloride solution concentration is 5%, the pH value is 6.5-7.2, and the spraying is continuous.

[0100] Viscosity test: According to GB / T2794-2013 "Determination of viscosity of adhesives", a rotational viscometer (NDJ-5S type) was used. The test temperature was 25℃, and the rotor speed was selected according to the viscosity range (20 rpm for 50-100 cP).

[0101] Table 1 compares the performance of siloxane polymer materials prepared by existing technologies and those prepared by this method (test methods refer to the above standards). The siloxane polymer materials prepared by existing technologies are considered prior art, while the anti-corrosion coatings prepared by this method are listed as examples. The comparison table is as follows:

[0102]

[0103]

[0104]

[0105] Table 1

[0106] The present invention discloses a siloxane alkyl polymer material with a specific degree of polymerization and its preparation method, and presents a specific process through Examples 1, 2, and 3. Each example clarifies the degree of polymerization of the siloxane alkyl polymer material and other raw material types in terms of raw material preparation. The raw material pretreatment adopts vacuum drying and molecular sieve dehydration. The material preparation is completed by batch feeding, controlling the stirring speed and the dropping speed, and the storage also has specific conditions. As can be seen from the performance comparison in Table 1, compared with the prior art, the materials prepared in these three examples have better performance in terms of degree of polymerization control, appearance, viscosity stability, pot life, curing time, tensile strength, elongation at break, and salt spray resistance.

[0107] In summary, this invention, with its specific degree of polymerization of siloxane polymer materials and preparation method, solves the batch variation problem caused by large fluctuations in the degree of polymerization of existing materials (Q-type 3.0-5.0, D-type 2.0-4.0, T-type 2.5-4.5) by precisely controlling the degree of polymerization of the relevant parts of the siloxane polymer materials (1.5, 1.2, 1.3 in Example 1, 2.0, 1.5, 2.0 in Example 2, and 2.7, 1.9, 2.7 in Example 3). Furthermore, the material outperforms existing technologies in terms of appearance (no particles, transparent), viscosity (50-90 cP at 25℃ and stable), tensile strength (3.5-4.5 MPa), and salt spray resistance (≥450 hours), thus meeting higher application requirements.

[0108] Furthermore, the raw materials are pretreated during preparation (e.g., the siloxane material in Example 1 is vacuum dried at 60°C for 3 hours, and the solvent is dehydrated by molecular sieve for 24 hours), and batch feeding and curing agent dripping are adopted, which solves the problems of water-containing raw materials and uneven mixing in existing processes; the storage conditions are clearly defined (e.g., sealed storage at 15°C and 50% relative humidity in Example 1) to avoid premature curing or delamination of the material; these improvements make the material more flexible to apply and can be used in harsh scenarios such as marine engineering and corrosion protection of chemical equipment.

[0109] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0110] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A siloxane polymer material with a specific degree of polymerization, characterized in that: It is composed of the following components: 20-30 parts of siloxane alkyl polymer material, 15-25 parts of polysulfide rubber, 10-20 parts of epoxy resin, 5-10 parts of curing agent, 10-20 parts of solvent, and 1-5 parts of additives; wherein the degree of polymerization of the siloxane alkyl polymer material is 1.3-2.7 for the Q-type related part, 1.0-1.9 for the D-type related part, and 1.1-2.7 for the T-type related part.

2. The siloxane polymer material with a specific degree of polymerization according to claim 1, characterized in that: The curing agent is an amine-based curing agent, the solvent is xylene, and the additive is a plasticizer.

3. A siloxane polymer material with a specific degree of polymerization according to claim 1, characterized in that: The polysulfide rubber is liquid polysulfide rubber, and the epoxy resin is bisphenol A type epoxy resin.

4. A method for preparing a siloxane polymer material with a specific degree of polymerization, comprising the siloxane polymer material with a specific degree of polymerization as described in claims 1-3, characterized in that: Includes the following steps: Step 1: Weigh out the siloxane polymer material, polysulfide rubber, epoxy resin, curing agent, solvent, and additives according to the specified proportions, and set aside. Step 2: Add epoxy resin to the mixing equipment, turn on the mixer, and stir at a speed of 200-300 rpm. Add solvent and stir for 5-10 minutes. Step 3: Add the siloxane polymer material and polysulfide rubber to the mixing equipment in sequence, and continue mixing for 10-15 minutes; Step 4: Add curing agent and additives, stir for 20-30 minutes until evenly mixed; Step 5: Filter the mixed material with a mesh size of 100-200 to obtain the siloxane polymer material with a specific degree of polymerization.

5. The method for preparing a siloxane polymer material with a specific degree of polymerization according to claim 4, characterized in that: Before weighing, the siloxane polymer material in step one needs to be vacuum dried at 60-80℃ for 2-3 hours, and then placed in a desiccator to cool to room temperature.

6. The method for preparing a siloxane polymer material with a specific degree of polymerization according to claim 4, characterized in that: The solvent added in step two needs to be dehydrated by molecular sieve. The molecular sieve is 4A molecular sieve, and the treatment time is 24-48 hours.

7. The method for preparing a siloxane polymer material with a specific degree of polymerization according to claim 4, characterized in that: In step three, the siloxane polymer material is added in two parts. The first part is 60%-70% of the total amount, and the remaining amount is added after stirring for 5 minutes.

8. The method for preparing a siloxane polymer material with a specific degree of polymerization according to claim 4, characterized in that: In step four, the curing agent is added by dripping at a rate of 1-2 drops per second. After the dripping is completed, continue stirring for 15-20 minutes.

9. The method for preparing a siloxane polymer material with a specific degree of polymerization according to claim 4, characterized in that: The material filtered in step five needs to be sealed and stored in a brown glass bottle. The storage environment temperature should be 15-25℃ and the relative humidity ≤60%.

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