Elastomer reinforcing agent, preparation method thereof and paper
By preparing and applying a nanoscale dispersed elastomer reinforcing agent to paper, the problems of poor folding endurance and bursting strength of traditional paper are solved, the folding endurance and ring crush performance of paper are improved, and its mechanical properties are enhanced.
Patent Information
- Application Number
- CN202510975133.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-15
- Publication Date
- 2025-12-02
AI Technical Summary
Traditional paper does not perform well in terms of folding endurance and bursting strength, which limits its application in applications that bear weight or pressure, and frequent folding can lead to fiber breakage and surface cracking.
An elastomer reinforcing agent containing monomers such as styrene and tert-butyl acrylate is used to form a prepolymer through a stepwise polymerization reaction. Combined with an initiator and a terminator, a nanoscale dispersed elastomer reinforcing agent is prepared and applied to paper fibers for chemical crosslinking.
It improves the folding endurance and ring crush resistance of paper, reduces damage during folding, and enhances the mechanical properties of paper.
Smart Images
Figure CN121045443A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of papermaking additives technology, specifically to elastomer reinforcing agents, their preparation methods, and paper. Background Technology
[0002] Paper, as an important carrier of information and culture, has a wide range of applications and a long history. Traditional paper is mainly composed of natural fibers linked by hexose sugars (see reference). Figure 1 Because of the relatively weak bonding between fibers, paper is easily damaged and creases when subjected to external impacts or folding. In other words, traditional paper performs poorly in terms of burst strength and folding resistance. This poor burst strength limits its application in situations requiring the paper to withstand weight or pressure, such as packaging and transportation. Furthermore, frequent folding can cause paper fibers to break, resulting in surface cracks or even complete rupture, severely impacting its usability and aesthetics.
[0003] Traditional paper strengthening agents that improve folding and bursting resistance are mainly classified into three categories: dry strength agents, ring crush strengthening agents, and stiffening agents. However, these strengthening agents have problems such as high cost, heavy production burden, or certain impacts on the environment and human health.
[0004] In view of this, the purpose of the present invention is to provide a new technical solution to solve the existing technical problems. Summary of the Invention
[0005] This application discloses an elastomer reinforcing agent, its preparation method, and paper, in order to solve the problems of poor folding endurance and bursting strength of existing paper, which limit its application.
[0006] The objective of this invention is achieved through the following technical solution:
[0007] The primary objective of this application is to provide an elastomer reinforcing agent comprising, by weight, the following raw materials: 70-80 parts of pure water, 11.5-14.5 parts of styrene, 3.0-4.0 parts of tert-butyl acrylate, 1.0-3.0 parts of isooctyl acrylate, 1.8-2.2 parts of glycidyl methacrylate, 1.0-1.5 parts of methyl methacrylate, 2.0-3.0 parts of ethyl acrylate, 0.03 parts of initiator, 0.18 parts by weight of terminator, and 1.3-1.5 parts of emulsifier.
[0008] In some specific embodiments, the following conditions are met: viscosity is 2-10 mPas.
[0009] and / or solids content of 24±2%,
[0010] and / or with a particle size of 50-80 nm,
[0011] And / or pH value of 1.7-2.6.
[0012] In some specific embodiments, the emulsifier is at least one of sodium dodecyl sulfate and nonylphenol polyoxyethylene ether.
[0013] In some specific embodiments, the emulsifier comprises, by weight, 0.4-0.5 parts sodium dodecyl sulfate and 0.9-1.0 parts nonylphenol polyoxyethylene ether.
[0014] In some specific embodiments, the initiator is ammonium persulfate.
[0015] In some specific embodiments, the terminator is tert-butyl hydroperoxide.
[0016] The second objective of this application is to provide a method for preparing an elastomer reinforcing agent, comprising the following steps:
[0017] S1. Mix the following raw materials in the reaction vessel according to the following parts by weight: 70-80 parts pure water, 11.5-14.5 parts styrene, 3.0-4.0 parts tert-butyl acrylate, 1.0-1.5 parts methyl methacrylate, 1.0-3.0 parts isooctyl acrylate, 1.8-2.2 parts glycidyl methacrylate, 2.0-3.0 parts ethyl acrylate, and 1.3-1.5 parts emulsifier;
[0018] S2. Stir the mixture of S1 thoroughly until dissolved, and then heat it in a water bath.
[0019] S3. Slowly add the initiator aqueous solution to the system obtained in S2 over a period of 2.0-2.5 hours, and then keep the reaction at the temperature for 2-3 hours.
[0020] S4. After the heat preservation is completed, 0.18 parts by weight of tert-butyl hydrogen peroxide is added to the system to terminate the reaction, and then the material is filtered out to obtain the elastomer reinforcing agent.
[0021] In some specific embodiments, the stirring rate in step S2 is 200 rpm, the water bath temperature is raised to 80-90°C, and the heating time is ≥30 min.
[0022] In some specific embodiments, the initiator aqueous solution comprises 0.03 parts by weight of ammonium persulfate and 5.0 parts by weight of pure water.
[0023] A third objective of this application is to provide a paper comprising the above-described elastomer reinforcing agent or an elastomer reinforcing agent prepared by the above-described preparation method.
[0024] The beneficial effects of this invention are:
[0025] The elastomer reinforcing agent described in this application has good mechanical properties and can be stretched and rebounded well. The viscosity of the elastomer reinforcing agent at room temperature is 2-10 mPas. Its solid content (24±2%) and particle size (50-80nm) work synergistically to achieve high penetration, uniform film formation and stable performance. When applied to paper, it can penetrate into the paper fiber gaps, disperse stress, reduce surface cracks in the paper, and improve the folding endurance and ring crush resistance of the paper.
[0026] The preparation method described in this application uses stepwise polymerization to control the polymerization reaction, construct a functional framework, and improve the conversion rate. Styrene and tert-butyl acrylate are used to form a prepolymer under the action of an initiator. The prepolymer serves as the matrix for the polymerization reaction, allowing other functional monomers to continue their polymerization reaction. The reaction temperature and time are controlled by the half-life of the initiator, and a terminator is used. This eliminates the need for complex purification processes and simplifies the process flow.
[0027] The paper described in this application uses an elastomer reinforcing agent, which is dispersed in the paper sample at the nanoscale and chemically cross-linked with its natural fiber structure, effectively ensuring long-term reinforcement and improving the paper's folding endurance and ring crush index. Attached Figure Description
[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0029] Figure 1 This is a schematic diagram of the natural fiber structure of traditional paper;
[0030] Figure 2 This is a schematic diagram of the synthesis principle of the present invention;
[0031] Figure 3 This is a schematic diagram illustrating the application principle of the elastomer reinforcing agent of this invention in paper;
[0032] Figure 4 This is a schematic diagram of the infrared spectrum after low-temperature drying in Embodiment 1 of the present invention. Detailed Implementation
[0033] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.
[0034] As used herein, “and / or” includes all combinations of any and one or more of the associated listed items. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a,” “an,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. Further understanding is needed; when used in this specification, “comprising” designates the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.
[0035] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Further understanding is that terms, such as those defined in common dictionaries, are interpreted in accordance with their meaning in the context of the relevant field and are not idealized or overly formal, unless expressly defined herein.
[0036] The exemplary invention described herein may suitably omit any one or more limiting elements, which are not specifically disclosed herein. Therefore, terms such as “comprising,” “including,” “containing,” etc., should be interpreted broadly and non-limitingly. Furthermore, the terminology used herein is for descriptive purposes without limitation, and it is unintentional to use terms that do not include any equivalent characteristics, but only to describe a portion of their characteristics; however, various modifications are possible within the scope of the invention according to the claims. Therefore, while the invention has been specifically disclosed through preferred embodiments and optional features, variations of the invention embodied by the modifications disclosed herein may be noted by those skilled in the art, and such modifications and variations are considered to be within the scope of the invention.
[0037] All raw materials or reagents used in the embodiments and comparative examples of this invention were purchased from mainstream manufacturers on the market. Those without specified manufacturers or concentrations are all analytical grade raw materials or reagents that are routinely available. There are no particular restrictions as long as they achieve the expected effect. The instruments and equipment used in this embodiment were all purchased from major manufacturers on the market. There are no particular limitations as long as they achieve the expected effect. Where specific techniques or conditions are not specified in this embodiment, they shall be performed in accordance with the techniques or conditions described in the literature in this field or according to the product instructions.
[0038] Terminology Explanation:
[0039] Folding endurance: This refers to the ability of paper to resist breaking after repeated folding. It is usually quantified by the number of times the paper is folded under standard test conditions.
[0040] Ring crush index: The ring crush index represents the compressive strength of paper or paperboard under ring compression, reflecting its ability to withstand vertical pressure.
[0041] Traditional paper is primarily composed of natural fibers linked by hexose sugars, resulting in relatively weak inter-fiber bonding. This makes the paper prone to breakage and creases when subjected to external impacts or folding. To address this, this invention provides an elastomer reinforcing agent. When applied in the papermaking process, it effectively improves the paper's folding endurance and ring crush index. The elastomer reinforcing agent of this invention comprises the following raw materials in parts by weight:
[0042] 70-80 parts pure water, 11.5-14.5 parts styrene, 3.0-4.0 parts tert-butyl acrylate, 1.0-3.0 parts isooctyl acrylate, 1.8-2.2 parts glycidyl methacrylate, 1.0-1.5 parts methyl methacrylate, 2.0-3.0 parts ethyl acrylate, 0.03 parts initiator, 0.18 parts by weight of terminator, and 1.3-1.5 parts emulsifier.
[0043] Styrene, as the main hard monomer, provides the rigid skeleton structure of the polymer, enhancing the mechanical strength and heat resistance of the elastomer; tert-butyl acrylate, as a soft monomer, imparts flexibility and elasticity to the polymer, which can balance the rigidity of styrene and form a copolymer network that combines rigidity and flexibility.
[0044] In some specific implementations, the initiator is ammonium persulfate (APS).
[0045] Ammonium persulfate ionizes in water to release ammonium ions (NH4+). + ) and persulfate ions (S2O8) 2- During the addition of persulfate, styrene (St) and tert-butyl acrylate (BA) emulsion copolymerization is initiated first to form a prepolymer. Then, it continues copolymerization with isooctyl acrylate (EHA), glycidyl methacrylate (GMA), methyl methacrylate, etc., to form an elastomer polymer. The reaction rates of St (hard monomer) and BA (soft monomer) are similar. Under the action of ammonium persulfate, preferential copolymerization can form uniform prepolymer segments, providing a stable reaction platform for the introduction of subsequent functional monomers (such as glycidyl methacrylate, isooctyl acrylate, etc.). If all monomers react simultaneously, differences in polarity and steric hindrance between different monomers may lead to uneven segment distribution or side reactions. Distributed polymerization can reduce such problems and ensure the regularity of the molecular chain structure. The synthesis principle is described in [reference needed]. Figure 2 .
[0046] As an exemplary implementation, based on the weight parts of the elastomer reinforcing agent, pure water accounts for 70-80 parts, such as 70, 71, 72, 73, 74, 75, 76, 77, 78, 79 or 80 parts.
[0047] In some specific implementations, the total solids content in the entire system is 25% of the pure water content.
[0048] In a specific embodiment, the elastomer reinforcing agent comprises the following raw materials in parts by weight:
[0049] 70-80 parts pure water, 11.5 parts styrene, 3.0 parts tert-butyl acrylate, 1 part isooctyl acrylate, 1.8 parts glycidyl methacrylate, 1.0 part methyl methacrylate, 2.0 parts ethyl acrylate, 0.03 parts initiator, 0.18 parts by weight of terminator, and 1.3 parts emulsifier.
[0050] Alternatively, an elastomer reinforcing agent comprising the following raw materials in parts by weight:
[0051] 70-80 parts pure water, 14.5 parts styrene, 4.0 parts tert-butyl acrylate, 3.0 parts isooctyl acrylate, 2.2 parts glycidyl methacrylate, 1.5 parts methyl methacrylate, 3.0 parts ethyl acrylate, 0.03 parts initiator, 0.18 parts by weight of terminator, and 1.5 parts emulsifier.
[0052] Alternatively, an elastomer reinforcing agent comprising the following raw materials in parts by weight:
[0053] 70-80 parts pure water, 13.0 parts styrene, 3.5 parts tert-butyl acrylate, 2.0 parts isooctyl acrylate, 2.0 parts glycidyl methacrylate, 1.2 parts methyl methacrylate, 2.5 parts ethyl acrylate, 0.03 parts initiator, 0.18 parts by weight of terminator, and 1.4 parts emulsifier.
[0054] In some specific embodiments, the emulsifier is at least one of sodium dodecyl sulfate and nonylphenol polyoxyethylene ether. Nonylphenol polyoxyethylene ether can be replaced with an environmentally friendly emulsifier.
[0055] In some specific embodiments, the emulsifier comprises, by weight, 0.4-0.5 parts sodium dodecyl sulfate and 0.9-1.0 parts nonylphenol polyoxyethylene ether.
[0056] In one specific embodiment, the product contains 0.4 parts sodium dodecyl sulfate and 0.9 parts nonylphenol polyoxyethylene ether by weight.
[0057] Alternatively, by weight, it contains 0.5 parts sodium dodecyl sulfate and 1.0 part nonylphenol polyoxyethylene ether.
[0058] Alternatively, by weight, it contains 0.45 parts sodium dodecyl sulfate and 0.95 parts nonylphenol polyoxyethylene ether.
[0059] In some specific implementations, the terminator is tert-butyl hydroperoxide.
[0060] Furthermore, the amount of initiator added is 0.12% of the total monomer content in the system, and the amount of terminator added is 0.73% of the total monomer content in the system.
[0061] In some specific embodiments, the elastomer reinforcing agent satisfies the following condition: viscosity of 2-10 mPas.
[0062] and / or solids content of 24±2%,
[0063] and / or with a particle size of 50-80 nm,
[0064] And / or pH value of 1.7-2.6.
[0065] Specifically, the elastomer reinforcing agent should meet the following requirements: viscosity of 2-10 mPas and solid content of 24±2%.
[0066] Alternatively, the elastomer reinforcing agent must meet the following requirements: viscosity of 2-10 mPas and particle size of 50-80 nm.
[0067] Alternatively, the elastomer reinforcing agent must meet the following requirements: viscosity of 2-10 mPas, solid content of 24±2%, and particle size of 50-80 nm.
[0068] Alternatively, the elastomer reinforcing agent must meet the following requirements: viscosity of 2-10 mPas and pH value of 1.7-2.6.
[0069] Alternatively, the elastomer reinforcing agent must meet the following requirements: solid content of 24±2%, viscosity of 2-10 mPas, particle size of 50-80 nm, and pH value of 1.7-2.6.
[0070] A second objective of this application is to provide a method for preparing an elastic reinforcing agent, comprising the following steps:
[0071] S1. Mix the following raw materials in the reaction vessel according to the following parts by weight: 70-80 parts pure water, 11.5-14.5 parts styrene, 3.0-4.0 parts tert-butyl acrylate, 1.0-1.5 parts methyl methacrylate, 1.0-3.0 parts isooctyl acrylate, 1.8-2.2 parts glycidyl methacrylate, 2.0-3.0 parts ethyl acrylate, 0.4-0.5 parts sodium dodecyl sulfate, and 0.9-1.0 parts nonylphenol polyoxyethylene ether;
[0072] S2. Stir the mixture from S1 thoroughly until dissolved, and then heat it in a water bath;
[0073] S3. Slowly add the initiator aqueous solution to the system obtained in S2 over a period of 2.0-2.5 hours, and then keep the reaction at the temperature for 2-3 hours.
[0074] S4. After the heat preservation is completed, 0.18 parts by weight of tert-butyl hydrogen peroxide is added to the system to terminate the reaction, and then the material is filtered out to obtain the elastomer reinforcing agent.
[0075] In this embodiment, the reaction vessel for S1 is a four-necked flask.
[0076] Furthermore, in S2, the stirring speed is 200 rpm, and the water bath is heated to 80-90℃, with a heating time of not less than 30 minutes.
[0077] In step S3, the initiator aqueous solution is prepared by dissolving 0.03 parts by weight of ammonium persulfate in 5.0 parts by weight of pure water and slowly added dropwise using a peristaltic pump. The dropwise addition of the initiator aqueous solution takes 2.0-2.5 hours, and after the addition is complete, the system is kept at a constant temperature for 2-3 hours.
[0078] Ammonium persulfate (APS) is used as an initiator. During the initial dropwise addition of the initiator, St and BA rapidly polymerize to form a prepolymer. Afterward, the remaining free radicals continue to initiate the copolymerization of functional monomers, reducing the residue of unreacted monomers. APS has a half-life of 2.1 h at 80-90℃. By slowly adding APS over 2-2.5 h and maintaining the reaction temperature for 2-3 h, continuous free radical generation can be ensured. Furthermore, the residual amount of APS after the reaction is almost negligible, eliminating the need for complex purification processes.
[0079] The elastomer reinforcing agents prepared according to the above method were subjected to various physical property tests, and the relevant test results are summarized in Table 1:
[0080] Table 1
[0081] Color milky white state liquid Solid content 24±2％ Viscosity (at room temperature) 2-10 mPas Particle size 50-80nm pH 1.7-2.6 PCD -30 to -70 μC / g stability It has been stable at room temperature for 10 days
[0082] As shown in Table 1, the elastomer product is a milky white liquid with a solid content of 24±2%, a viscosity (at room temperature) of 2-10 mPas, a particle size of 50-80 nm, a pH value of 1.7-2.6, and a PCD of -30 to -70 μC / g, indicating that the polymer is an anionic polymer and can remain stable at room temperature for more than 10 days.
[0083] Reference Figure 4 The elastomer reinforcing agent prepared according to the above method was dried at low temperature and then subjected to infrared detection. Its value was at 3458.58 cm⁻¹. -1 2926.65cm -1 1726.65cm -1 1603.17cm -1 1499.51cm -1 1178.89cm -1Characteristic peaks were observed in all samples, with the peak at 3458.58 cm⁻¹. -1 The peak at 2926.65 cm⁻¹ is a broad peak stretched from the -OH group, indicating separation from methyl methacrylate by the carboxylic acid group; -1 The location is an aliphatic CH stretch, 1726.65cm. -1 One peak corresponds to the carbonyl group in methyl methacrylate, isooctyl acrylate, glycidyl methacrylate, and ethyl acrylate; the peak is located at 1603.17 cm⁻¹. -1 The presence of styrene groups is indicated at this location; furthermore, the peak value is located at 1499.51 cm⁻¹. -1 The position may be related to the C=C stretching vibration of styrene aromatic hydrocarbons, and it also represents the bending vibration of the CH bond in aromatic carbons; 1178.89 cm -1 This refers to the CO stretching of the ester bonds in butyl acrylate, 2-ethylhexyl acrylate, glycidyl methacrylate, and ethyl acrylate.
[0084] In addition, this application also provides a paper comprising an elastomer reinforcing agent having the above-mentioned components.
[0085] The principle behind the application of this elasticity enhancer in paper is as follows:
[0086] Reference Figure 3 The base paper is composed of cellulose fibers, thus possessing numerous hydroxyl (-OH) functional groups. A gray-background, blank handmade paper sample is used. The sample is immersed in an aqueous solution of an elastomer reinforcing agent, which penetrates into the gaps between the paper fibers. During high-temperature drying in an oven, the elastomer reinforcing agent quickly adheres tightly to the fibers through physical interactions (physical adsorption of colloid particles, filling of fiber network gaps) and chemical interactions (hydrogen bonding, chemical cross-linking). The elastomer reinforcing agent and paper fibers form a filling and bonding structure, which disperses stress within the paper, reducing damage during folding and thus improving its folding endurance.
[0087] The following description, in conjunction with specific embodiments, comparative examples, and blank samples, further illustrates an elastomer reinforcing agent and paper of the present invention:
[0088] Example 1
[0089] First, weigh out 70 parts by weight of pure water, 13.5 parts by weight of styrene, 3 parts by weight of tert-butyl acrylate, 1 part by weight of methyl methacrylate, 2 parts by weight of isooctyl acrylate, 2 parts by weight of glycidyl methacrylate, 2 parts by weight of ethyl acrylate, 0.5 parts by weight of sodium lauryl sulfate, and 1 part by weight of nonylphenol polyoxyethylene ether into a four-necked flask, and start stirring at 200 rpm until all components are dissolved.
[0090] Then, place the above system in a water bath and heat it to 85°C for at least 30 minutes.
[0091] Preparation of initiator solution: Weigh 0.03 parts of ammonium persulfate (APS), dissolve it completely in 5.0 parts of pure water, and prepare an initiator aqueous solution;
[0092] Next, after the water bath reaches the set temperature, the initiator aqueous solution is slowly added dropwise using a peristaltic pump. The addition time is controlled to be 2-2.5 hours. After the addition is completed, the system is kept at the temperature for 2-3 hours to react.
[0093] Finally, after the heat preservation is completed, 0.18 parts by weight of tert-butyl hydrogen peroxide is added to the system to terminate the reaction. Then, the material is filtered out to obtain the elastomer reinforcing agent, which is then bottled and labeled.
[0094] Example 2
[0095] First, weigh out 70 parts by weight of pure water, 12.5 parts of styrene, 3.5 parts of tert-butyl acrylate, 1 part of methyl methacrylate, 2 parts of isooctyl acrylate, 2 parts of glycidyl methacrylate, 2.5 parts of ethyl acrylate, 0.5 parts of sodium lauryl sulfate, and 1 part of nonylphenol polyoxyethylene ether into a four-necked flask, and start stirring at 200 rpm until all components are dissolved.
[0096] Then, place the above system in a water bath and heat it to 85°C for at least 30 minutes.
[0097] Preparation of initiator solution: Weigh 0.03 parts of ammonium persulfate (APS), dissolve it completely in 5.0 parts of pure water, and prepare an initiator aqueous solution;
[0098] Next, after the water bath reaches the set temperature, the initiator aqueous solution is slowly added dropwise using a peristaltic pump. The addition time is controlled to be 2-2.5 hours. After the addition is completed, the system is kept at the temperature for 2-3 hours to react.
[0099] Finally, after the heat preservation is completed, 0.18 parts by weight of tert-butyl hydrogen peroxide is added to the system to terminate the reaction. Then, the material is filtered out to obtain the elastomer reinforcing agent, which is then bottled and labeled.
[0100] Example 3
[0101] First, weigh out 70 parts by weight of pure water, 13.6 parts by weight of styrene, 3.2 parts by weight of tert-butyl acrylate, 1 part by weight of methyl methacrylate, 1 part by weight of isooctyl acrylate, 2.2 parts by weight of glycidyl methacrylate, 2.2 parts by weight of ethyl acrylate, 0.5 parts by weight of sodium lauryl sulfate, and 1 part by weight of nonylphenol polyoxyethylene ether into a four-necked flask, and start stirring at 200 rpm until all components are dissolved.
[0102] Then, place the above system in a water bath and heat it to 85°C for at least 30 minutes.
[0103] Preparation of initiator solution: Weigh 0.03 parts of ammonium persulfate (APS), dissolve it completely in 5.0 parts of pure water, and prepare an initiator aqueous solution;
[0104] Next, after the water bath reaches the set temperature, the initiator aqueous solution is slowly added dropwise using a peristaltic pump. The addition time is controlled to be 2-2.5 hours. After the addition is completed, the system is kept at the temperature for 2-3 hours to react.
[0105] Finally, after the heat preservation is completed, 0.18 parts by weight of tert-butyl hydrogen peroxide is added to the system to terminate the reaction. Then, the material is filtered out to obtain the elastomer reinforcing agent, which is then bottled and labeled.
[0106] Example 4
[0107] First, weigh out 70 parts by weight of pure water, 11.5 parts of styrene, 4 parts of tert-butyl acrylate, 1.5 parts of methyl methacrylate, 3 parts of isooctyl acrylate, 2 parts of glycidyl methacrylate, 3 parts of ethyl acrylate, 0.5 parts of sodium lauryl sulfate, and 1 part of nonylphenol polyoxyethylene ether into a four-necked flask, and start stirring at 200 rpm until all components are dissolved.
[0108] Then, place the above system in a water bath and heat it to 85°C for at least 30 minutes.
[0109] Preparation of initiator solution: Weigh 0.03 parts of ammonium persulfate (APS), dissolve it completely in 5.0 parts of pure water, and prepare an initiator aqueous solution;
[0110] Next, after the water bath reaches the set temperature, the initiator aqueous solution is slowly added dropwise using a peristaltic pump. The addition time is controlled to be 2-2.5 hours. After the addition is completed, the system is kept at the temperature for 2-3 hours to react.
[0111] Finally, after the heat preservation is completed, 0.18 parts by weight of tert-butyl hydrogen peroxide is added to the system to terminate the reaction. Then, the material is filtered out to obtain the elastomer reinforcing agent, which is then bottled and labeled.
[0112] Comparative Example 1:
[0113] Comparative Example 1-1 differs from Example 1 in that it does not contain glycidyl methacrylate and the amount of styrene used is 13.5 parts.
[0114] Comparative Examples 1-2 differ from Example 1 in that they do not contain glycidyl methacrylate and the amount of styrene used is 14.5 parts.
[0115] Comparative Examples 1-3 differ from Example 1 in that they do not contain glycidyl methacrylate and the amount of styrene used is 11.5 parts.
[0116] Comparative Example 2:
[0117] The difference between Comparative Example 2-1 and Example 1 is that the system does not contain isooctyl acrylate and the amount of styrene used is 13.5 parts.
[0118] The difference between Comparative Example 2-2 and Example 1 is that the system does not contain isooctyl acrylate, and the amount of styrene used is 14.5 parts.
[0119] The difference between Comparative Examples 2-3 and Example 1 is that the system does not contain isooctyl acrylate, and the amount of styrene used is 11.5 parts.
[0120] Comparative Example 3:
[0121] The difference between Comparative Example 3-1 and Example 1 is that the system does not contain methyl methacrylate and the amount of styrene used is 13.5 parts.
[0122] The difference between Comparative Example 3-2 and Example 1 is that the system does not contain methyl methacrylate and the amount of styrene used is 14.5 parts.
[0123] The difference between Comparative Example 3-3 and Example 1 is that the system does not contain methyl methacrylate and the amount of styrene used is 11.5 parts.
[0124] Comparative Example 4:
[0125] The difference between Comparative Example 4-1 and Example 1 is that the system does not contain tert-butyl acrylate and the amount of styrene used is 13.5 parts.
[0126] The difference between Comparative Example 4-2 and Example 1 is that the system does not contain tert-butyl acrylate, and the amount of styrene used is 14.5 parts.
[0127] The difference between Comparative Examples 4-3 and Example 1 is that the system does not contain tert-butyl acrylate and the amount of styrene used is 11.5 parts.
[0128] Blank sample:
[0129] Pure water in the same weight proportion as in Example 1.
[0130] The elastomer reinforcing agents obtained in Examples 1-4 above were applied to paper, and the specific application process is as follows:
[0131] First, paper selection: gray-backed, white-blank handmade paper, beating degree 30°SR, basis weight 80g / m³. 2 ;
[0132] Then, weigh 2.5g of the original elastomer reinforcing agent solution obtained in Example 1, put it in an oven and dry it at 120°C for 3 hours, and screen the samples with better film formation for immersion experiments;
[0133] Next, the dried elastomer reinforcement sample was diluted to 5% with pure water, and 80 g / m 2 After soaking the quantitative paper sample in the sample solution for 1 minute, remove it, use absorbent paper to naturally absorb the excess solution on the paper surface, and then transfer it to an oven to dry at 120℃ for 20 minutes to obtain the finished paper.
[0134] Finally, the paper was allowed to reach equilibrium moisture for 12 hours to obtain paper sample RA162, which is Example-1. The paper sample was tested for thickness, folding endurance, and ring crush, and the data were recorded.
[0135] Similarly, the elastomer reinforcing agents obtained in Examples 2, 3, and 4 were applied to paper samples using the above-described operation to obtain Examples-2, 3, and 4 of paper sample RA162. Thickness, folding endurance, and ring crush tests were performed on each sample, and the data were recorded.
[0136] Similarly, the elastomer reinforcing agent and blank sample (pure water) obtained in Comparative Examples 1-4 were applied to paper samples using the above operation to obtain paper samples RA162#1, RA162#2, RA162#3, RA162#4 and blank, respectively. Thickness, folding endurance and ring crush test were performed on each sample, and the data were recorded.
[0137] The relevant test results of Example 1, Comparative Examples 1-4, and blank samples are summarized in Table 2:
[0138] Table 2
[0139]
[0140] As shown in Table 2, the folding endurance of the RA162 series samples obtained in Example 1 was significantly better than that of the blank sample. Among them, the folding endurance of the sample in Example-2 reached 15 times, which was 5 times that of the blank sample. This indicates that applying the elastomer reinforcing agent of the present invention to paper can effectively improve the folding endurance of paper. In addition, the ring crush index of the RA162 series reached more than 6.39 N·m / g, which was significantly higher than that of the blank sample group. This indicates that the use of the elastic reinforcing agent of the present invention can increase the mechanical properties of paper. The improvement of mechanical properties helps the paper to remain intact when folded and reduces the generation of cracks and creases.
[0141] Compared with Comparative Example 1, Example 1 shows that the addition of glycidyl methacrylate helps the elastomer reinforcing agent to enhance the folding endurance and mechanical properties of paper. Compared with the blank sample, Comparative Example 1 shows that the polymer formed by styrene, tert-butyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl acrylate, etc., helps to enhance the folding endurance and mechanical properties of paper, but its reinforcing effect is not as good as that of the elastic reinforcing agent.
[0142] Compared with Comparative Example 2, Example 1 shows that the addition of isooctyl acrylate helps the elastomer reinforcing agent to enhance the folding endurance and mechanical properties of paper. Compared with the blank sample, Comparative Example 2 shows that the polymer formed by styrene, tert-butyl acrylate, glycidyl methacrylate, methyl methacrylate, ethyl acrylate, etc., helps to enhance the folding endurance and mechanical properties of paper, but its reinforcing effect is not as good as that of the elastic reinforcing agent.
[0143] Compared with Comparative Example 3, Example 1 shows that methyl methacrylate helps the elastomer reinforcing agent to enhance the folding endurance and mechanical properties of paper; compared with the blank sample, Comparative Example 3 shows that the polymer formed by styrene, tert-butyl acrylate, glycidyl methacrylate, methyl methacrylate, ethyl acrylate, etc., helps to enhance the folding endurance and mechanical properties of paper, but its reinforcing effect is not as good as that of the elastic reinforcing agent.
[0144] Compared with Comparative Example 4, Example 1 shows that tert-butyl acrylate helps the elastomer reinforcing agent to enhance the folding endurance and mechanical properties of paper; compared with the blank sample, Comparative Example 4 shows that the polymer formed by styrene, glycidyl methacrylate, methyl methacrylate, ethyl acrylate, etc., helps to enhance the folding endurance and mechanical properties of paper, but its reinforcing effect is not as good as that of the elastic reinforcing agent.
[0145] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.
Claims
1. An elastomer reinforcing agent, characterized in that, By weight, it includes the following raw materials: 70-80 parts pure water, 11.5-14.5 parts styrene, 3.0-4.0 parts tert-butyl acrylate, 1.0-3.0 parts isooctyl acrylate, 1.8-2.2 parts glycidyl methacrylate, 1.0-1.5 parts methyl methacrylate, 2.0-3.0 parts ethyl acrylate, 0.03 parts initiator, 0.18 parts by weight terminator, and 1.3-1.5 parts emulsifier.
2. The elastomer reinforcing agent according to claim 1, characterized in that, Satisfies: viscosity of 2-10 mPas. and / or solids content of 24±2%, and / or with a particle size of 50-80 nm, And / or pH value of 1.7-2.
6.
3. The elastomer reinforcing agent according to claim 1, characterized in that, The emulsifier is at least one of sodium dodecyl sulfate and nonylphenol polyoxyethylene ether.
4. The elastomer reinforcing agent according to claim 3, characterized in that, The emulsifier comprises, by weight, 0.4-0.5 parts sodium dodecyl sulfate and 0.9-1.0 parts nonylphenol polyoxyethylene ether.
5. The elastomer reinforcing agent according to claim 1, characterized in that, The initiator is ammonium persulfate.
6. The elastomer reinforcing agent according to claim 1, characterized in that, The terminator is tert-butyl hydroperoxide.
7. A method for preparing the elastomer reinforcing agent according to any one of claims 1-6, characterized in that, Includes the following steps: S1. Mix the following raw materials in the reaction vessel according to the following parts by weight: 70-80 parts pure water, 11.5-14.5 parts styrene, 3.0-4.0 parts tert-butyl acrylate, 1.0-1.5 parts methyl methacrylate, 1.0-3.0 parts isooctyl acrylate, 1.8-2.2 parts glycidyl methacrylate, 2.0-3.0 parts ethyl acrylate, and 1.3-1.5 parts emulsifier; S2. Stir the mixture of S1 thoroughly until dissolved, and then heat it in a water bath. S3. Slowly add the initiator aqueous solution to the system obtained in S2 over a period of 2.0-2.5 hours, and then keep the reaction at the temperature for 2-3 hours. S4. After the heat preservation is completed, 0.18 parts by weight of tert-butyl hydrogen peroxide is added to the system to terminate the reaction, and then the material is filtered out to obtain the elastomer reinforcing agent.
8. The preparation method according to claim 7, characterized in that, In step S2, the stirring rate is 200 rpm, the water bath temperature is raised to 80-90℃, and the heating time is ≥30 min.
9. The preparation method according to claim 7, characterized in that, The initiator aqueous solution comprises 0.03 parts by weight of ammonium persulfate and 5.0 parts by weight of pure water.
10. A type of paper, characterized in that: It includes the elastomer reinforcing agent according to any one of claims 1-6 or the elastomer reinforcing agent prepared by the preparation method according to any one of claims 7-9.