Chlorinated butyl rubber calendered adhesive tape and preparation method thereof

Abstract

The invention discloses a chlorinated butyl rubber calendered adhesive tape and a preparation method thereof, and relates to the technical field of protective material preparation, the calendered adhesive tape comprises a fabric skeleton layer, and rubber protective layers are compounded on the two sides of the fabric skeleton layer; the rubber protection layer is prepared by vulcanizing a rubber compound, and the rubber compound comprises the following components in parts by weight: chlorinated butyl rubber, natural rubber, montmorillonite, a vulcanization system and a compounding agent. The preparation method comprises the steps of rubber compound preparation, calendering compounding and vulcanization. Through cooperative use of the chlorinated butyl rubber, the natural rubber and the montmorillonite, the calendering manufacturability of the rubber material is effectively improved, the protection performance is improved while high production efficiency, low cost and no solvent pollution are guaranteed, and the rubber material is suitable for manufacturing high-performance wearable protection equipment.

Description

Technical Field

[0001] This invention relates to the field of protective material preparation technology, and in particular to a chemically protective calendered sheet, specifically a chlorinated butyl rubber calendered sheet and its preparation method. Background Technology

[0002] Chlorinated butyl rubber is a polymer compound produced by passing chlorine gas through a butyl rubber solution. It retains the inherent properties of butyl rubber, such as excellent acid and alkali resistance, resistance to toxic agent solubility, low permeability and diffusion, and high storage stability, safety, and heat resistance. Therefore, the product can protect personnel's skin from harm in environments containing radioactive dust, chemical agents, biological warfare agents, and toxic and hazardous industrial chemicals, enabling safe and effective rescue and disaster relief operations. Consequently, chlorinated butyl rubber has become the preferred material for respiratory and skin protection in the current market.

[0003] Currently, skin protective tapes based on chlorinated butyl rubber are mainly prepared using a coating process. However, the coating process has a long production cycle, low efficiency, and the organic solvents used in the coating process are flammable and explosive. The volatilization of these organic solvents not only poses a threat to the health of operators but also causes environmental pollution.

[0004] Compared to coating processes, calendering has a shorter production cycle and lower cost, and it eliminates the problems of solvent evaporation and environmental pollution. Currently, calendering has become a core technology in rubber sheet manufacturing. However, in the preparation of chlorinated butyl rubber calendered sheets, due to the high density of side methyl groups in the chlorinated butyl rubber molecular chain, its compact structure, and high cohesive energy give it excellent vibration and impact energy absorption properties. During calendering, under the same pressure, chlorinated butyl rubber absorbs more pressure energy, reducing the force acting between the chlorinated butyl rubber and the skeleton material, resulting in insufficient bonding strength and poor ductility of the rubber compound. This makes calendering single-component chlorinated butyl rubber difficult. Figure 3 As shown.

[0005] In the prior art, in order to reduce the cohesive energy of chlorinated butyl rubber, flexible monomers or plasticizers are usually added to chlorinated butyl rubber during the calendering process. Although this method can improve the performance problems of chlorinated butyl rubber in the calendering process of a single rubber type, the protective performance of the blended rubber is significantly reduced as the content of flexible monomers and plasticizers increases, and it is impossible to achieve good calenderability while maintaining protective performance.

[0006] Therefore, there is an urgent need to develop a novel calendering sheet that can maintain the excellent protective properties of chlorinated butyl rubber while also possessing good calendering process performance. Based on this, this application proposes a chlorinated butyl rubber calendering sheet and its preparation method. Summary of the Invention

[0007] To address the problems of current skin protective tapes based on chlorinated butyl rubber, which suffer from long production cycles, low efficiency, and harmful substance generation during coating processes, as well as poor rubber extensibility and difficulty in calendering chlorinated butyl rubber alone, and reduced protective performance when adding flexible monomers or plasticizers, this invention provides a chlorinated butyl rubber calendered tape and its preparation method.

[0008] This invention is achieved using the following techniques: This invention provides a chlorinated butyl rubber calendered fabric, comprising a fabric skeleton layer, with rubber protective layers laminated on both sides of the fabric skeleton layer; the rubber protective layers are made by vulcanizing a compound, the compound components, by weight, comprising: 50-90 parts chlorinated butyl rubber, 10-50 parts natural rubber, 2-6 parts montmorillonite, a vulcanization system, and compounding agents.

[0009] In practice, the fabric skeleton layer serves as the mechanical skeleton of the entire chlorinated butyl rubber calendered fabric, providing the main tensile strength, tear resistance, and dimensional stability. Rubber protective layers are laminated on both sides of the fabric skeleton layer, providing airtightness and a protective barrier against toxic and hazardous chemicals. The thickness of the fabric skeleton layer is 0.15~0.20mm, and the thickness of the chlorinated butyl rubber calendered fabric is 0.4±0.05mm. The rubber protective layer is made by vulcanizing a compound rubber, the components of which, by weight, include: 50~90 parts chlorinated butyl rubber, 10~50 parts natural rubber, 2~6 parts montmorillonite, a vulcanization system, and compounding agents.

[0010] Natural rubber, through its flexible molecular chains, embeds itself into the gaps between the molecular chains of chlorinated butyl rubber, effectively reducing the cohesive energy of the rubber compound and greatly improving its ductility and calendering processability. Montmorillonite, selected at the nanoscale, forms intercalation or exfoliation structures within the rubber matrix, constituting a dense physical barrier layer that effectively slows down the diffusion and penetration paths of gases and small-molecule liquids. The vulcanization system includes zinc oxide, industrial sulfur, and an accelerator; specifically, the vulcanization system, by weight, includes: Zinc oxide: 6-10 parts; Accelerator TMTD: 0.5~1.5 parts; Accelerator DM: 0.5~1.0 parts; Industrial sulfur: 0.1~0.5; Compounding agents include one or more of the following: vulcanization activators, scorch inhibitors, fillers, colorants, antioxidants, and tackifiers. Specifically, the compounding agents, by weight, include: Industrial stearic acid, 1.0~3.0 parts; Magnesium oxide: 0.3~1.0 parts; CTP (Cytochlor) anti-scorching agent: 0.1~0.5 parts; Lidex powder: 10-18 parts; Phthalocyanine green: 0.5~1.5 parts; Anti-aging agent 264: 0.5~1.5 parts; Anti-aging agent D: 0.1~0.5 parts; Gum rosin: 0.5~2.0 parts.

[0011] This invention provides a method for preparing chlorinated butyl rubber calendered fabric, comprising the following steps: a. Preparation of compound rubber Chlorinated butyl rubber, natural rubber, montmorillonite, vulcanization system, and compounding agents are mixed to prepare a homogeneous compound. Mixing includes the following steps: Adjust the roller gap to 1.5mm~2mm, and plasticize the natural rubber into three segments for 10min~15min. This breaks down the molecular chains of the natural rubber, reduces its elasticity, and achieves the necessary plasticity. ab, adjust the roller gap to 1.5mm~2mm, plasticize the chlorinated butyl rubber for 7min~8min, preheat and soften it evenly. Adjust the roller gap to 8mm~10mm, mix the plasticized chlorinated butyl rubber with the three-stage natural rubber, and press for 5min~6min to ensure that the chlorinated butyl rubber and the three-stage natural rubber are fully dispersed and integrated to form a uniform continuous phase. ad. Adjust the roller gap to 8mm~10mm, add industrial stearic acid, magnesium oxide, scorch inhibitor CTP, lithopone, phthalocyanine green, antioxidant 264, antioxidant D, and rosin, and mix for 15min~20min to fully disperse them into the rubber matrix. Adjust the roller gap to 8mm~10mm, add montmorillonite and the vulcanization system, and mix for 10min~15min. The vulcanization system includes zinc oxide, industrial sulfur, accelerator TMTD, and accelerator DM. After thinning and passing through the film, the following steps are taken: adjust the roller gap to 0.5mm~1mm, pass through the film for 10min~15min, adjust the roller gap to 8mm~10mm, and mix and pass the film for 10min~15min to form a dense film that is easy for subsequent processing.

[0012] b, Calendering composite Before calendering and compounding, the compound is hot-refined for 20-30 minutes to achieve a plasticity of 0.35-0.55 Vickers, thereby restoring the thermoplasticity and softness of the rubber compound to meet the requirements of the calendering process. The compound obtained in step a is calendered and laminated with the fabric skeleton layer on both sides using a calender. After cooling and talc separation, it is wound up to form a calendered rubber sheet; specifically: Open the main steam valve of the calender equipment, adjust the temperature of the three rolls of the calender to 92~118℃ for the upper roll, 80~100℃ for the middle roll, and 60~80℃ for the lower roll, and preheat it; Wrap the base fabric around the wooden stick of the front traction device; After the equipment is preheated, start the calendering equipment and the linked winding device, adjust the distance between the three rollers and the roller speed, and perform double-sided calendering. The thickness of the calendered fabric is 0.4±0.05mm.

[0013] After calendering, the rubber sheet passes through a cooling device and a talc powder isolation device, and is then wound up by a winding device.

[0014] c, sulfidation The calendered rubber sheet is vulcanized in a vulcanizing tank at a temperature of 130±5℃ for 78~90 min and a pressure of 0.38~0.4 MPa.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The chlorinated butyl rubber calendering fabric and its preparation method provided by this invention utilize natural rubber with good compatibility and complementary properties. During the mixing process, the natural rubber is dispersed in the continuous phase of the chlorinated butyl rubber in the form of micro-regions, or the two form an interpenetrating network structure. This effectively increases the spatial distance between the molecular chains of the chlorinated butyl rubber, dilutes the chain segment density, and reduces the cohesive energy of the chlorinated butyl rubber. This makes the rubber compound easier to stretch and shape during calendering, solves the agglomeration phenomenon of the chlorinated butyl rubber itself during calendering, and solves the problem that chlorinated butyl rubber alone is difficult to calender.

[0016] Furthermore, the addition of nano-sized montmorillonite to the mixed rubber matrix of natural rubber and chlorinated butyl rubber results in a relatively uniform intercalation or exfoliation structure in the rubber matrix, with small interlayer spacing. The montmorillonite sheets form a dense barrier in the rubber matrix, effectively blocking the diffusion of toxic gas or liquid molecules through the synergistic effect of chlorinated butyl rubber, natural rubber, and nano-montmorillonite.

[0017] This application utilizes the shearing force of the calender roller gap to penetrate the rubber compound into the internal gaps of the textile structure and cover the fabric surface, completely avoiding the use of organic solvents and eliminating their hazards to operators and the environment. The production process is safer and more environmentally friendly. The calendering process itself has the advantages of short production cycle, high efficiency, and low cost, forming a rubberized fabric with specific strength, flexibility, protection, and waterproof properties, suitable for use as the main material of wearable protective equipment. The fabric has a smooth surface, uniform thickness, low shrinkage, and good internal density, giving it market value. Tests have shown that the resulting chlorinated butyl rubber calendered fabric provides extremely long protection against highly toxic chemicals such as mustard gas, nitrogen tetroxide, and unsymmetrical dimethylhydrazine, as well as strong corrosive oxidants. Under the premise of short production cycle, low cost, and no harmful substances generated by the calendering process, the protective function is ensured not to be diminished by process improvements, making it more competitive in the market. Attached Figure Description

[0018] Figure 1 This is a schematic diagram showing the structure of the high-bonding-strength hot-melt rubber-based composite material of the present invention. The diagram only shows the layer structure and does not show the layer thickness.

[0019] Figure 2 This refers to the chlorinated butyl rubber calendered fabric prepared according to the present invention.

[0020] Figure 3 This indicates that the product is obtained by calendering a single chlorinated butyl rubber in the existing technology.

[0021] In the diagram: 1-rubber protective layer, 2-fabric skeleton layer. Detailed Implementation

[0022] The specific embodiments of the present invention will be described in detail below. Example 1

[0023] A method for preparing chlorinated butyl rubber calendered sheet, such as... Figure 1 , 2 As shown, the steps are as follows: a. Preparation of compound rubber Weigh the raw materials according to the weight ratio as follows: 75 parts chlorinated butyl rubber, 25 parts natural rubber, 5 parts montmorillonite, 8.9 parts zinc oxide, 0.99 parts accelerator TMTD, 0.6 parts accelerator DM, 0.3 parts industrial sulfur, 1.5 parts industrial stearic acid, 0.3 parts magnesium oxide, 0.2 parts scorch inhibitor CTP, 14.85 parts lithopone, 1.0 part phthalocyanine green, 1.0 part antioxidant 264, 0.5 parts antioxidant D, 1.0 part rosin.

[0024] Adjust the roller gap to 1.5mm~2mm, and plasticize the natural rubber into three sections of natural rubber for 10min~15min. Adjust the roller gap to 1.5mm~2mm, and plasticize the chlorinated butyl rubber for 7min~8min. Adjust the roller gap to 8mm~10mm, mix the plasticized chlorinated butyl rubber with the three-stage natural rubber, and press for 5min~6min. Adjust the roller gap to 8mm~10mm, add industrial stearic acid, magnesium oxide, scorch inhibitor CTP, lithopone, phthalocyanine green, antioxidant 264, antioxidant D, and rosin, and mix for 15min~20min. Adjust the roller gap to 8mm~10mm, add montmorillonite, zinc oxide, industrial sulfur, accelerator TMTD, and accelerator DM, and mix for 10min~15min. Adjust the roller gap to 0.5mm~1mm, pass through the thin film for 10min~15min, adjust the roller gap to 8mm~10mm, and mix and unload the film for 10min~15min; A uniform compound was prepared. b, Calendering composite Before calendering and compounding, the compound is hot-melted for 20-30 minutes to achieve a plasticity of 0.35-0.55 Vickers. The compound obtained in step a is calendered and laminated with the fabric skeleton layer 2 on both sides using a calender. After cooling and talc separation, it is wound up to form a calendered rubber sheet; specifically: Open the main steam valve of the calender equipment, adjust the temperature of the three rolls of the calender to 92~118℃ for the upper roll, 80~100℃ for the middle roll, and 60~80℃ for the lower roll, and preheat it; Wrap the base fabric around the wooden stick of the front traction device; After the equipment is preheated, start the calendering equipment and the linked winding device, adjust the distance between the three rollers and the roller speed, and perform double-sided calendering. The thickness of the calendered fabric is 0.4±0.05mm.

[0025] After calendering, the rubber sheet passes through a cooling device and a talc powder isolation device, and is then wound up by a winding device.

[0026] c, sulfidation The calendered rubber sheet is vulcanized in a vulcanizing tank at a vulcanization temperature of 130±5℃ for 78~90min and a pressure of 0.38~0.4Mpa to obtain the calendered rubber sheet. The calendered rubber sheet is a multi-layer rubber composite material, with a strong textile skeleton material in the middle and composite rubber material on both the inner and outer layers. Example 2

[0027] A method for preparing chlorinated butyl rubber calendered sheet, such as... Figure 1 As shown, Weigh the raw materials according to the weight ratio as follows: 80 parts chlorinated butyl rubber, 20 parts natural rubber, 3 parts montmorillonite, 8.9 parts zinc oxide, 0.99 parts accelerator TMTD, 0.6 parts accelerator DM, 0.3 parts industrial sulfur, 1.5 parts industrial stearic acid, 0.3 parts magnesium oxide, 0.2 parts scorch inhibitor CTP, 14.85 parts lithopone, 1.0 part phthalocyanine green, 0.8 parts antioxidant 264, 0.4 parts antioxidant D, 1.0 part rosin.

[0028] Except for the above proportions, everything else is the same as in Example 1.

[0029] Observation of the calendered sheets obtained in Examples 1 and 2 shows that the calendered sheets all have smooth surfaces and uniform thickness. The calendered fabrics prepared in Examples 1 and 2 were tested for mustard gas protection time, nitrogen tetroxide protection time, and unsymmetrical dimethylhydrazine protection time. The results are shown in the table below.

[0030]

[0031] The results showed that the prepared calendered fabric could effectively defend against the penetration, diffusion, and corrosion damage of mustard gas, nitrogen tetroxide, and unsymmetrical dimethylhydrazine.

[0032] The scope of protection claimed by this invention is not limited to the specific embodiments described above. Moreover, for those skilled in the art, this invention can have various modifications and alterations. Any modifications, improvements, and equivalent substitutions made within the concept and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A chlorinated butyl rubber calendered sheet, characterized in that: It includes a fabric skeleton layer (2), and rubber protective layers (1) are laminated on both sides of the fabric skeleton layer (2); the rubber protective layer (1) is made by vulcanizing a compound rubber, and the compound rubber components, by weight, include: 50-90 parts of chlorinated butyl rubber, 10-50 parts of natural rubber, 2-6 parts of montmorillonite, vulcanization system and compounding agents.

2. The chlorinated butyl rubber calendered sheet according to claim 1, characterized in that: The vulcanization system includes zinc oxide, industrial sulfur, and an accelerator.

3. The chlorinated butyl rubber calendered sheet according to claim 2, characterized in that: The vulcanization system comprises, by weight, parts of: Zinc oxide: 6-10 parts; Accelerator TMTD: 0.5~1.5 parts; Accelerator DM: 0.5~1.0 parts; Industrial sulfur: 0.1~0.

5.

4. The chlorinated butyl rubber calendered sheet according to claim 1, characterized in that: The compounding agent includes one or more of the following: vulcanization activator, scorch inhibitor, filler, colorant, antioxidant, and thickener.

5. The chlorinated butyl rubber calendered sheet according to claim 4, characterized in that: The compounding agent comprises, by weight, the following: Industrial stearic acid, 1.0~3.0 parts; Magnesium oxide: 0.3~1.0 parts; CTP (Cytochlor) anti-scorching agent: 0.1~0.5 parts; Lidex powder: 10-18 parts; Phthalocyanine green: 0.5~1.5 parts; Anti-aging agent 264: 0.5~1.5 parts; Anti-aging agent D: 0.1~0.5 parts; Gum rosin: 0.5~2.0 parts.

6. The chlorinated butyl rubber calendered sheet according to claim 1, characterized in that: The thickness of the fabric skeleton layer (2) is 0.15~0.20mm, and the thickness of the chlorinated butyl rubber calendered cloth is 0.4±0.05mm.

7. A method for preparing chlorinated butyl rubber calendering sheet as described in any one of claims 1 to 6, characterized in that, Includes the following steps: a. Preparation of compound rubber Chlorinated butyl rubber, natural rubber, montmorillonite, vulcanization system, and compounding agents are mixed to prepare a homogeneous compound. b, Calendering composite The compound obtained in step a is calendered and laminated with the fabric skeleton layer (2) on both sides by a calender. The temperature of the upper roller of the calender is 92~118℃, the temperature of the middle roller is 80~100℃, and the temperature of the lower roller is 60~80℃. After cooling and talc powder isolation, it is wound up to form the calendered rubber sheet. c, sulfidation The calendered rubber sheet is vulcanized in a vulcanizing tank at a temperature of 130±5℃ for 78~90 min and a pressure of 0.38~0.4 MPa.

8. The method for preparing a chlorinated butyl rubber calendered sheet according to claim 7, characterized in that: In step a, mixing Includes the following steps: aa, plasticize natural rubber into three sections of natural rubber, plasticizing for 10-15 minutes. ab, plasticize the chlorinated butyl rubber for 7-8 minutes. ac, mix the plasticized chlorinated butyl rubber with three sections of natural rubber, and press for 5-6 minutes. Add industrial stearic acid, magnesium oxide, scorch inhibitor CTP, lithopone, phthalocyanine green, antioxidant 264, antioxidant D, and rosin, and mix for 15-20 minutes. Add montmorillonite and the vulcanization system (including zinc oxide, industrial sulfur, accelerator TMTD, and accelerator DM) and mix for 10-15 minutes. af, thin pass, mixed and loaded.

9. The method for preparing a chlorinated butyl rubber calendered sheet according to claim 7, characterized in that: Before calendering and compounding, the compound is hot-melted to achieve a plasticity of 0.35~0.55 Vickers.

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