A light fireproof board and preparation method thereof

Abstract

The present application relates to the technical field of fireproof board preparation, and specifically to a light fireproof board and a preparation method thereof, the method comprising: mixing and stirring PVC, phenolic resin, bisphenol F type glycidyl ether epoxy resin, polyamide and foaming agent, then adding plasticizer, flame retardant and foaming regulator, continuing stirring, and foaming treatment; in the foaming process, analyzing the foaming temperature difference at each measuring position, combining PID controller to intelligently control the ambient temperature of PVC foaming, and obtaining the foam substrate after the foaming treatment; coating the surface of the foam substrate with resin after sanding and dust removal, and then covering it with a layer of fireproof layer to obtain an intermediate product, stacking and cold pressing the multiple layers of intermediate products, naturally curing to form a semi-finished product, cutting off the excess part of the edge and removing burrs, and obtaining a PVC foamed light fireproof board. The present application can avoid the problem of uneven foaming during the foaming process of fireproof board preparation and improve the preparation quality of fireproof board.

Description

Technical Field

[0001] The present application relates to the technical field of fireproof board preparation, and in particular to a lightweight fireproof board and a preparation method thereof. Background Art

[0002] Fireproof boards are generally inorganic fireproof materials, which have many advantages such as self-insulation, not easy to break, not easy to deform, and fireproof. Various fireproof boards are used in various places in life. For example, the application of fireproof boards in the actual power construction process can significantly improve the safety and fireproof performance of the overall power system; the application of fireproof boards on the exterior walls of buildings can play a role in heat preservation, fire prevention, corrosion resistance, etc., and improve the quality of the building. Therefore, the research on fireproof boards has important market value.

[0003] At present, there are various fireproof boards on the market, among which PVC foam fireproof boards have the advantages of light weight, fire resistance and stable structure, and are generally applicable to the field of building boards. For example, the Chinese invention patent with patent publication number CN106166885A discloses a method for preparing PVC foam fireproof boards, which explains that in the process of preparing PVC foam lightweight fireproof boards, it is necessary to first prepare a foam substrate with fireproof performance, and control and adjust the temperature of the board through a temperature control component to ensure that the prepared foam substrate has good density structure and strength characteristics. However, since the ambient temperature during foaming will have a great impact on the temperature of the board, and the existing preparation process cannot accurately adjust and control the ambient temperature during foaming, it is easy to cause the problem of uneven foaming in the mixture, thereby affecting the density structure and strength characteristics of the foam substrate, so that the fireproof performance of the PVC foam lightweight fireproof board prepared later is poor. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of this application is to provide a lightweight fireproof board and a preparation method thereof. The technical solutions adopted are as follows:

[0005] The present invention provides a method for preparing a lightweight fireproof board, comprising the following steps:

[0006] PVC, phenolic resin, bisphenol F glycidyl ether epoxy resin, polyamide and foaming agent are mixed and stirred, and then a plasticizer, a flame retardant and a foaming regulator are added and stirred continuously, and foaming treatment is performed to obtain a foam substrate; during the foaming process, the foaming temperature of each measuring position in the mixture at each sampling time within the sampling time period is obtained;

[0007] At any sampling moment, the foaming temperature difference value of each measuring position is obtained based on the degree of difference in foaming temperature between each measuring position and the adjacent measuring position, the mixed material area is evenly divided into multiple foaming temperature areas, and the bubble non-uniformity of each foaming temperature area is obtained based on the difference in foaming temperature difference values ​​of all measuring positions in each foaming temperature area and the change of foaming temperature difference in each foaming temperature area, and the density difference of PVC foaming at any sampling moment is obtained in combination with the difference between each foaming temperature area and other foaming temperature areas regarding the change of foaming temperature difference;

[0008] According to the discrete degree of density difference of PVC foaming at all sampling moments within the sampling time period and the temperature of PVC foaming at the current moment, the feedback ambient temperature of PVC foaming at the current moment is determined, and the ambient temperature of PVC foaming at the current moment is controlled by a PID controller, and the foam substrate is obtained after the preset foaming time;

[0009] The foam substrate is sanded and dusted, and then the surface is coated with resin. After the resin dries automatically, a fireproof layer is covered on the coated surface of the foam substrate to obtain an intermediate product. Multiple layers of the intermediate products are stacked, pressed and placed in a cold press machine for cold pressing. The cold-pressed intermediate products are naturally cured to form a semi-finished product; the excess part of the edge of the semi-finished product is cut off, and the surface burrs are removed to obtain a PVC foamed lightweight fireproof board.

[0010] Preferably, the weight proportions of the components before foaming are: 20 parts of PVC, 30-45 parts of phenolic resin, 30-45 parts of bisphenol F glycidyl ether epoxy resin, 3-8 parts of polyamide, 2-18 parts of plasticizer, 5-10 parts of foaming agent, 2-8 parts of flame retardant, and 5-12 parts of foaming regulator.

[0011] Preferably, the foaming time is set to 40 minutes.

[0012] Preferably, the method for obtaining the foaming temperature difference value at each measuring position is:

[0013] At each sampling moment, the average value of the difference between the temperature value at each measuring position and all temperature values ​​in the temperature window is taken as the foaming temperature difference at each measuring position, and the difference between the temperature values ​​refers to the absolute value of the difference between two temperature values.

[0014] Preferably, obtaining the bubble non-uniformity of each foaming temperature zone further includes:

[0015] Arrange the foaming temperature difference values ​​of all measuring positions in each foaming temperature zone at each sampling moment from small to large to form a foaming temperature difference sequence of each foaming temperature zone at each sampling moment;

[0016] , where is the bubble non-uniformity in the jth foaming temperature zone, is the data mean in the first-order difference sequence of the foaming temperature difference sequence in the jth foaming temperature zone, is the number of measurement positions in the jth foaming temperature zone, and are the foaming temperature differences of the sth and s-1th measuring positions in the jth foaming temperature zone, respectively.

[0017] Preferably, the calculation formula for the density difference of PVC foaming at any sampling time is: , where is the density difference of PVC foam at sampling time t, is the foaming discrete difference value and bubble non-uniformity of the j-th foaming temperature zone, is a normalized function, G is the number of foaming temperature zones; wherein the foaming discrete difference value of the jth foaming temperature zone is obtained by calculating the difference in the degree of change of the foaming temperature difference between the jth foaming temperature zone and other foaming temperature zones.

[0018] Preferably, the calculation formula corresponding to the foaming discrete difference value of the j-th foaming temperature zone is: , where and are the standard deviations of the foaming temperature difference series in the j-th and g-th foaming temperature zones, respectively.

[0019] Preferably, the corresponding calculation formula of the feedback ambient temperature when the PVC is foaming at the current moment is:

[0020] , where It is the feedback environment temperature when PVC is foaming at the current moment. is the ambient temperature of PVC foaming at the current moment, To adjust the threshold, is an exponential function with a natural constant as base, is the discrete coefficient of the density difference of PVC foam at all sampling moments within the sampling period, The maximum adjustment temperature value.

[0021] Preferably, the coating amount of the resin coated on the surface of the foam substrate is 110 , the pressure of the cold press is 1.5 , the temperature is 45℃.

[0022] The embodiment of the present application also provides a lightweight fireproof board, which is prepared by using any of the steps of the lightweight fireproof board preparation method described above.

[0023] From the above, it can be seen that the lightweight fireproof board and the preparation method thereof provided by the present application have at least the following beneficial effects:

[0024] The present application constructs a foaming temperature difference value based on the analysis of the foaming temperature change characteristics of all measurement positions at each sampling time, reflecting the significant characteristics of the foaming phenomenon at different positions, so that the subsequent analysis of the inconsistent foaming density characteristics can be more accurate; the bubble non-uniformity is constructed based on the change gradient of the foaming temperature difference sequence in the foaming temperature area, and the discrete difference value is constructed based on the difference between the discrete characteristics of the foaming temperature difference sequence in different foaming temperature areas. The normalized result of the bubble non-uniformity is used as the weight to perform weighted summation on the foaming discrete difference values, thereby extracting the foaming density difference characteristics at a deeper level, obtaining the density difference, and reflecting the difference between each sampling. The characteristic of inconsistent foaming density during the foaming process at each moment is taken into consideration, and the feedback ambient temperature is constructed based on the excessively chaotic change characteristics of the density difference at each sampling moment, and the ambient temperature during foaming is accurately adjusted and controlled by the PID controller based on the feedback ambient temperature. Compared with the existing process, the present application deeply extracts the foaming density difference in the PVC foaming process, and adjusts and controls the ambient temperature during foaming based on the change characteristics of the foaming density difference, so as to avoid the problem of uneven foaming in the mixture, improve the density structure and strength characteristics of the foam substrate, and thus improve the fire resistance of the PVC foamed lightweight fireproof board. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A flowchart of the steps of a method for preparing a lightweight fireproof board provided in this application;

[0027] Figure 2 A schematic diagram of the foaming environment temperature control process provided for this application;

[0028] Figure 3 This is a schematic diagram of the comparison of foaming environment temperatures provided in this application. DETAILED DESCRIPTION

[0029] In order to further explain the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the following is a detailed description of a lightweight fireproof board and its preparation method proposed in accordance with the present application, its specific implementation, structure, features and effects, in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0030] Unless otherwise specified and limited, terms such as "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a circuit structure, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such articles or devices. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the article or device including the element. In addition, the term "and\or" used herein includes any and all combinations of one or more related listed items. All technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application.

[0031] The specific scheme of a lightweight fireproof board and a preparation method thereof provided by the present application is described in detail below with reference to the accompanying drawings.

[0032] See also Figure 1 , which shows a flow chart of a method for preparing a lightweight fireproof board provided by an embodiment of the present application, comprising the following steps:

[0033] The first embodiment of this application:

[0034] S1, PVC, phenolic resin, bisphenol F glycidyl ether epoxy resin, polyamide and foaming agent are mixed and stirred, and then a plasticizer, a flame retardant and a foaming regulator are added, and the mixture is continuously stirred, and foaming treatment is performed to obtain a foam substrate.

[0035] Specifically, in the first embodiment of the present application, the raw materials for preparing the foam substrate include the following components in parts by weight: 20 parts of PVC, 40 parts of phenolic resin, 40 parts of bisphenol F type glycidyl ether epoxy resin, 6 parts of polyamide, 10 parts of plasticizer, 7 parts of foaming agent, 6 parts of flame retardant, and 8 parts of foaming regulator. Further, 20 parts of PVC, 40 parts of phenolic resin, 40 parts of bisphenol F type glycidyl ether epoxy resin, 6 parts of polyamide and 7 parts of foaming agent are mixed and stirred at a temperature of 40°C, wherein the stirring speed is 800r / min, and the stirring time in this embodiment is half an hour; secondly, after continuing to add 10 parts of plasticizer, 6 parts of flame retardant, and 8 parts of foaming regulator, the mixture is stirred at an initial stirring speed of 600r / min in this embodiment, and the temperature is increased for foaming treatment, and the preset foaming time is 40min, and finally the foam substrate is obtained.

[0036] It should be noted that in actual application scenarios, the stirring speed and stirring time are set by the implementer according to actual conditions, and this application does not impose any special restrictions.

[0037] In the above-mentioned process of heating up for foaming treatment, the temperature is mostly fixed when preparing the foam substrate (the comparative example in this application is a fixed temperature of 80°C), but considering that PVC foaming will cause significant changes in temperature, inaccurate control of the ambient temperature during PVC foaming will affect the quality of PVC foaming, and easily cause the problem of uneven foaming in the mixture, thereby affecting the density structure and strength characteristics of the foam substrate, and making the fireproof performance of the subsequently prepared PVC foamed lightweight fireproof board poor. Therefore, this application analyzes the temperature characteristics in the foaming process of preparing the foam substrate, and accurately adjusts and controls the ambient temperature of PVC foaming according to the temperature characteristics in the foaming process, solves the problem of uneven foaming in the mixture, improves the density structure and strength characteristics of the foam substrate, and then improves the fireproof performance of the subsequently prepared PVC foamed lightweight fireproof board.

[0038] In this embodiment, the PVC foaming temperature at the current moment is regulated by analyzing the PVC foaming characteristics during the foaming process within a preset sampling time period before the current moment. The temperature control process during the foaming process is specifically as follows:

[0039] Step 1: During the foaming process, obtain the foaming temperature of each measuring position in the mixture at each sampling time.

[0040] During the PVC foaming process, the foaming temperature of the PVC in the mixture is collected by the high temperature resistant infrared probe of the infrared thermal imager. In this embodiment, the collection time interval is 10s, the sampling time period is 10min, and the temperature of all measurement positions at each sampling time in the sampling time period before the current moment is obtained. In the actual application process, the measurement position and the temperature data collection time interval are set by the implementer according to the actual situation, and this application does not impose any special restrictions.

[0041] Step 2: For any sampling moment, the foaming temperature difference value of each measuring position is obtained based on the degree of difference in foaming temperature between each measuring position and the adjacent measuring position, and the mixed material area is evenly divided into multiple foaming temperature zones. Based on the difference in foaming temperature difference values ​​of all measuring positions in each foaming temperature zone and the change of foaming temperature difference in each foaming temperature zone, the bubble non-uniformity of each foaming temperature zone is obtained, and the density difference of PVC foaming at any sampling moment is obtained in combination with the difference between each foaming temperature zone and other foaming temperature zones regarding the change of foaming temperature difference.

[0042] Normally, when the ambient temperature is too high during the PVC foaming process, due to the influence of the uneven mixing of the foaming agent and the foaming regulator, it is easy to cause large differences in the foaming reaction at different positions of the mixture, resulting in uneven foaming size and inconsistent foaming density at different positions; and when the ambient temperature is too low during the PVC foaming process, it is easy to cause insufficient PVC foaming, that is, the ambient temperature is too high or too low during the PVC foaming process. The density structure and strength characteristics of the final foam substrate. At the same time, PVC foaming will cause temperature changes. The greater the temperature change in the local area of ​​a certain position, the more obvious the foaming temperature difference characteristics of the PVC material at that position in the mixture. Therefore, in order to realize intelligent regulation of temperature during the PVC foaming process, this embodiment analyzes the foaming temperature difference characteristics of PVC materials at different positions in the mixture.

[0043] In order to analyze the foaming temperature difference characteristics at different positions during the foaming process, the temperature data of each measuring position at each sampling time is set with each measuring position as the center. The temperature window of each measurement position is used as the temperature window. If the temperature data in the temperature window is insufficient, When , the missing data are filled with the mean temperature value within the temperature window.

[0044] The purpose of setting the temperature window is to extract the local features of the pixel points. Therefore, under the premise of meeting this condition, the size of the temperature window can be set by the implementer. In this application, the value of N is an odd number between 5 and 11. Preferably, in one embodiment of the present application, the size of the temperature window is 7*7.

[0045] In this embodiment, any sampling time is taken as an example. For any sampling time, the foaming temperature difference at each measuring position is calculated. The specific method is:

[0046] At each sampling time, the average value of the difference between the temperature value at each measurement position and all the temperature values ​​in the temperature window is taken as the foaming temperature difference at each measurement position, and the difference between the temperature values ​​refers to the absolute value of the difference between the two temperature values. The greater the temperature difference between the central measurement position and other measurement positions in the temperature window, to a certain extent, it indicates that the temperature change caused by PVC foaming at the central measurement position of the temperature window is greater, that is, the more significant the foaming phenomenon at this position is, the greater the foaming temperature difference is.

[0047] Generally, if the ambient temperature is too high during the PVC foaming process, due to the uneven mixing of the foaming agent and the foaming regulator, it is easy to cause the difference between the foaming temperature difference characteristics at different measurement positions to be greater, resulting in greater differences in the foaming expansion of the mixture at different positions, which in turn leads to uneven bubbles during PVC foaming. At the same time, the greater the foaming temperature difference, the easier it is to cause changes in the hardness and density of the foam substrate, which in turn changes the degree of wear during subsequent sanding and dust removal, affecting the uniformity of the sanding effect and the surface finish.

[0048] Based on the above analysis, the mixture area is evenly divided into 64 foaming temperature zones. For each sampling moment, the foaming temperature differences at all measuring positions in each foaming temperature zone are sequenced in ascending order, which is recorded as the foaming temperature difference sequence of each foaming temperature zone at each sampling moment.

[0049] If there is a high gradient change between all adjacent data in the foaming temperature difference sequence of the foaming temperature zone, it means that the greater the difference in the foaming temperature difference in the foaming temperature zone, the more likely it is to cause uneven bubbles during PVC foaming. Further, the first-order difference sequence of the foaming temperature difference sequence is extracted. The larger the data mean in the first-order difference sequence, the more non-uniform the foaming temperature difference characteristics in the foaming temperature zone, the higher the degree of change in the foaming temperature difference, the greater the characteristics that characterize the foaming abnormality, and the more likely it is that the foaming temperature zone will have uneven foaming. At the same time, if obvious uneven foaming occurs in each foaming temperature zone at this time, it will have a greater impact on the foaming density. At this time, the foaming environment temperature should be feedback-regulated to ensure that the prepared foam substrate has a good density structure and strength characteristics.

[0050] For each sampling moment, calculate the bubble non-uniformity in each foaming temperature region:

[0051] , where is the bubble non-uniformity in the jth foaming temperature zone, is the data mean in the first-order difference sequence of the foaming temperature difference sequence in the jth foaming temperature zone, is the number of measurement positions in the jth foaming temperature zone, and are the foaming temperature differences at the sth and s-1th measuring positions in the jth foaming temperature zone, respectively.

[0052] The data mean in the first-order difference sequence of the foaming temperature difference sequence can reflect the average gradient change between all adjacent data in the foaming temperature difference sequence. By averaging the gradient change and combining the difference in foaming temperature difference at different measuring positions, the non-uniform characteristics of bubbles in the foaming temperature area can be measured more accurately, which is used to improve the accuracy of subsequent feedback adjustment of the foaming environment temperature.

[0053] At the same time, if the difference between the discrete degrees of the foaming temperature difference characteristics of different foaming temperature zones at a certain sampling moment is greater, the difference in the foaming expansion of the mixture at that sampling moment will be greater, and the phenomenon of inconsistent foaming density of the mixture will be more significant.

[0054] In order to extract the characteristics of inconsistent foaming density at different sampling moments, the difference between each foaming temperature zone and other foaming temperature zones in this embodiment regarding the change of foaming temperature difference is calculated, and the foaming discrete difference value of each foaming temperature zone is calculated. In this embodiment, the specific expression is:

[0055] , where is the foaming discrete difference value of the jth foaming temperature zone, is the number of foaming temperature zones, and are the standard deviations of the foaming temperature difference series of the jth and gth foaming temperature zones, respectively. The greater the difference between the standard deviations of the foaming temperature difference series, the greater the difference in the discrete characteristics of the foaming temperature difference between this foaming temperature zone and other foaming temperature zones. This means that this foaming temperature zone is more likely to have inconsistent foaming density characteristics, and the greater the discrete difference value.

[0056] Furthermore, the bubble non-uniformity of each foaming temperature zone is combined with the foaming discrete difference value to calculate the density difference of PVC foaming at each sampling time, and the expression is:

[0057] , where is the density difference of PVC foam at sampling time t, is the normalization function, is the exponential normalized value of bubble non-uniformity, which is used as the weight of the foaming discrete difference value. At sampling time t, the greater the bubble non-uniformity of all foaming temperature regions and the greater the foaming discrete difference value, the greater the difference in PVC foaming density between different positions in the mixture at the sampling time, and the greater the density difference, that is, at this time, the foaming density difference tends to change excessively chaotically, and then the PVC foaming becomes out of control. At this time, it is more necessary to control and adjust the foaming environment temperature to avoid serious impact on the density structure and strength characteristics of the foam substrate.

[0058] Step 3: According to the discrete degree of density difference of PVC foaming at all sampling moments within the sampling time period and the temperature of PVC foaming at the current moment, determine the feedback ambient temperature of PVC foaming at the current moment, use PID controller to control the ambient temperature of PVC foaming at the current moment, and obtain the foam substrate after the preset foaming time.

[0059] Normally, in the process of preparing the foam substrate, if the foaming environment temperature is too high, the chemical reaction rate in the mixture will be excessively accelerated, causing the foaming density difference at different sampling times during the foaming process to show excessively chaotic change characteristics, which can easily lead to uncontrolled PVC foaming, thereby affecting the density structure and strength characteristics of the final prepared foam substrate; if the foaming environment temperature is too low, the change of the foaming density difference at different sampling times during the foaming process is relatively stable, resulting in insufficient PVC foaming, which will also affect the density structure and strength characteristics of the final prepared foam substrate.

[0060] Therefore, the discrete degree of the difference in foaming density during the sampling period of the foaming process is analyzed, and then the feedback ambient temperature of the PVC foaming at the current moment is calculated. In this embodiment, the specific calculation formula is:

[0061] , where It is the feedback environment temperature when PVC foaming at the current moment. is the ambient temperature of PVC foaming at the current moment, is the adjustment threshold, and the range of the adjustment threshold is [0.45, 0.55]. The function of the adjustment threshold is to determine the adjustment direction and adjustment size of the ambient temperature. If the adjustment threshold is too large or too small, it will affect the ability to increase or decrease the ambient temperature. In order to avoid affecting the ability to increase or decrease the ambient temperature, in this embodiment, the adjustment threshold is set to 0.5. is an exponential function with a natural constant as base, is the discrete coefficient of density difference of PVC foam at all sampling moments within the sampling period, is the maximum adjustment temperature value, the value range of the maximum adjustment temperature value is [15, 20]. The function of the maximum adjustment temperature value is to determine the maximum change of the foaming environment temperature. The maximum change of the foaming environment temperature is not easy to be too large or too small. In this embodiment, the value is 18, wherein the calculation of the discrete coefficient is a well-known technology, and the specific process will not be repeated.

[0062] It can be understood that the larger the dispersion coefficient of PVC foaming density difference, the more it can reflect the excessive chaotic change characteristics of foaming density difference, indicating that the ambient temperature for foaming is relatively too high at this time, and the smaller the feedback ambient temperature; conversely, the smaller the dispersion coefficient of PVC foaming density difference, the more it can reflect that the change of foaming density difference is relatively stable, and the phenomenon of insufficient PVC foaming will occur, indicating that the ambient temperature for foaming is relatively too low at this time, and the larger the feedback ambient temperature.

[0063] In order to accurately adjust and control the ambient temperature during the PVC foaming process, the feedback ambient temperature of the current PVC foaming and the ambient temperature of the current PVC foaming are input into the PID controller. The PID controller adjusts the foaming ambient temperature by calculating the actual error between the feedback ambient temperature and the ambient temperature of the current PVC foaming. The PID controller obtains the control signal of the foaming ambient temperature, and then controls the foaming ambient temperature, thereby more accurately adjusting and controlling the PVC foaming temperature. Specifically, the schematic diagram of the foaming ambient temperature control process is as follows Figure 2 shown.

[0064] The foaming process is continued by adjusting the controlled foaming environment temperature until a preset foaming time is reached, and finally a foam substrate is prepared.

[0065] At this point, according to the above process of this embodiment, the temperature during the foaming process can be adjusted to obtain the foaming environment temperature, and the foaming process is continued for a preset time (40 minutes in this embodiment) at the adjusted foaming environment temperature to prepare a foam substrate.

[0066] S2, sanding and dust removal of the foam substrate, then coating the surface with resin, and waiting for the resin to dry automatically.

[0067] Specifically, in this embodiment, the prepared foam substrate is placed on a sanding machine for sanding, and the dust on the surface of the foam substrate is removed. The surface of the foam substrate after sanding and dust removal is coated with resin, and the coating amount of the resin is 110 , wait for the resin to dry automatically;

[0068] S3, a fireproof layer is coated on the surface of the coated foam substrate to obtain an intermediate product, multiple layers of the intermediate products are stacked, pressed and placed in a cold press, and the cold pressed intermediate products are naturally cured to form a semi-finished product.

[0069] Specifically, in this embodiment, a fireproof layer is coated on the surface of the coated foam substrate to obtain an intermediate product, and multiple layers of the intermediate products are stacked together, pressed for half an hour, and then placed in a cold press for cold pressing, wherein the pressure of the cold press is 1.5 In this embodiment, the temperature is 45°C and the pressing time is 6 hours; the cold-pressed intermediate product is placed at room temperature for natural curing and derivatization for 3 days to form a semi-finished product. It should be noted that in actual application scenarios, the cold pressing time and natural curing time are set by the implementer, and this application does not impose any special restrictions on this.

[0070] S4, cutting off the excess part of the edge of the semi-finished product and removing the surface burrs to obtain a PVC foamed lightweight fireproof board.

[0071] The second embodiment of the present application:

[0072] In the process of preparing the foam substrate in S1, the raw materials for preparing the foam substrate include the following components in parts by weight: 20 parts of PVC, 30 parts of phenolic resin, 30 parts of bisphenol F glycidyl ether epoxy resin, 3 parts of polyamide, 3 parts of plasticizer, 3 parts of foaming agent, 3 parts of flame retardant, and 3 parts of foaming regulator, wherein the process of preparing the foam substrate by processing each component according to the weight parts in this embodiment, and the temperature control process during the foaming process are the same as those in the first embodiment, and will not be repeated in this embodiment. Similarly, S2-S4 in this embodiment are exactly the same as those in the first embodiment, and will not be repeated here.

[0073] The third embodiment of the present application:

[0074] In the process of preparing the foam substrate in S1, the raw materials for preparing the foam substrate include the following components in parts by weight: 20 parts of PVC, 45 parts of phenolic resin, 45 parts of bisphenol F glycidyl ether epoxy resin, 8 parts of polyamide, 18 parts of plasticizer, 10 parts of foaming agent, 8 parts of flame retardant, and 12 parts of foaming regulator, wherein the process of preparing the foam substrate by processing each component according to the weight parts in this embodiment, and the temperature control process during the foaming process are the same as those in the first embodiment, and will not be repeated here. Similarly, S2-S4 in this embodiment are exactly the same as those in the first embodiment, and will not be repeated here.

[0075] Furthermore, in order to measure the quality of the fireproof board prepared by combining the method in the three embodiments of the present application with the temperature control during the foaming process, a comparative example is set in the present application, and the temperature of the foaming process in the comparative example is fixed at 80°C, that is, the temperature of the foaming process in the comparative example is not controlled by the method of steps one to three of the present application. Apart from this, the remaining processes and steps of the comparative example are exactly the same as those of the first embodiment of the present application. The foaming environment temperatures obtained by the temperature control during the above-mentioned foaming process in the three embodiments of the present application and the foaming environment temperature of the comparative example are shown in the schematic diagram. Figure 3 The specific comparison results are shown in Table 1.

[0076] Table 1

[0077]

[0078] In Table 1, the three embodiments of the present application adjust the temperature of the foaming process through the temperature control step in the foaming process of the present application. The dry volume density of the fireproof boards prepared by the three embodiments of the present application is less than the dry volume density of the fireproof boards of the comparative example. The compressive strength of the fireproof boards prepared by the three embodiments is higher than the compressive strength of the fireproof boards prepared by the comparative example. Among them, the smaller the dry volume density, the better the lightness of the fireproof board, and the greater the compressive strength, the higher the strength of the fireproof board.

[0079] Based on the same inventive concept as the above method, an embodiment of the present application further provides a lightweight fireproof board, which is prepared by the steps of any one of the above-mentioned methods for preparing a lightweight fireproof board.

[0080] It is to be understood that the sequence of the embodiments of the present application described above is for description only and does not represent the advantages and disadvantages of the embodiments. The above describes specific embodiments of the present specification. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0081] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0082] The above content is only an implementation method of the present application and is not intended to limit the scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the protection scope of the present application.

Claims

1. A method for preparing a lightweight fireproof board, characterized in that: The following steps are involved: PVC, phenolic resin, bisphenol F glycidyl ether epoxy resin, polyamide and foaming agent are mixed and stirred, and then a plasticizer, a flame retardant and a foaming regulator are added and stirred continuously, and foaming treatment is performed to obtain a foam substrate; during the foaming process, the foaming temperature of each measuring position in the mixture at each sampling time within the sampling time period is obtained; At each sampling moment, the average value of the difference between the temperature value at each measuring position and all the temperature values ​​in the temperature window is taken as the foaming temperature difference value at each measuring position. The difference between the temperature values ​​refers to the absolute value of the difference between two temperature values. The mixed material area is divided into multiple foaming temperature areas. The sequence composed of the foaming temperature difference values ​​of all measuring positions in each foaming temperature area at each sampling moment is recorded as the foaming temperature difference sequence. According to the data mean in the first-order difference sequence of the foaming temperature difference sequence and the foaming temperature difference values ​​of adjacent measuring positions, the bubble non-uniformity of the foaming temperature area is obtained, and the density difference of PVC foaming at any sampling moment is calculated. The expression is: , , where is the density difference of PVC foam at sampling time t, is the foaming discrete difference value and bubble non-uniformity of the j-th foaming temperature zone, is a normalized function, G is the number of foaming temperature regions, and are the standard deviations of the foaming temperature difference series in the jth and gth foaming temperature zones, respectively; Determine the feedback ambient temperature of PVC foaming at the current moment, recorded as , The expression is: , is the ambient temperature of PVC foaming at the current moment, To adjust the threshold, is an exponential function with a natural constant as base, is the discrete coefficient of the density difference of PVC foam at all sampling moments within the sampling period, In order to adjust the temperature value to the maximum, the PID controller is used to control the ambient temperature of the PVC foaming at the current moment, and the foam substrate is obtained after the preset foaming time; The foam substrate is sanded and dusted, and then the surface is coated with resin, and the resin is allowed to dry automatically; a fireproof layer is applied on the surface of the coated foam substrate to obtain an intermediate product, multiple layers of the intermediate products are stacked, pressed, and placed in a cold press, and the cold-pressed intermediate products are naturally cured to form a semi-finished product; the excess part of the edge of the semi-finished product is cut off, and the surface burrs are removed to obtain a PVC foamed lightweight fireproof board; The expression of bubble non-uniformity in the foaming temperature region is: , where is the data mean in the first-order difference sequence of the foaming temperature difference sequence in the jth foaming temperature zone, is the number of measurement positions in the jth foaming temperature zone, and are the foaming temperature differences of the sth and s-1th measuring positions in the jth foaming temperature zone, respectively.

2. A method for preparing a lightweight fireproof board according to claim 1, characterized in that: Before the foaming treatment, the weight proportions of the components are: 20 parts of PVC, 30-45 parts of phenolic resin, 30-45 parts of bisphenol F glycidyl ether epoxy resin, 3-8 parts of polyamide, 2-18 parts of plasticizer, 5-10 parts of foaming agent, 2-8 parts of flame retardant, and 5-12 parts of foaming regulator.

3. A method for preparing a lightweight fireproof board according to claim 1, characterized in that: The foaming time is set to 40 minutes.

4. A method for preparing a lightweight fireproof board according to claim 1, characterized in that: The amount of resin applied on the foam substrate is 110 The pressure of the cold press is 1.5 , the temperature is 45℃.

5. A lightweight fireproof board, characterized in that: The lightweight fireproof board is prepared by using the steps of a lightweight fireproof board preparation method as described in any one of claims 1 to 4.

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