CN115594818A - Square frame type fragile cover and preparation method thereof - Google Patents

Square frame type fragile cover and preparation method thereof Download PDF

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Publication number
CN115594818A
CN115594818A CN202211340109.0A CN202211340109A CN115594818A CN 115594818 A CN115594818 A CN 115594818A CN 202211340109 A CN202211340109 A CN 202211340109A CN 115594818 A CN115594818 A CN 115594818A
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China
Prior art keywords
parts
mold
temperature
oil
polyol
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Pending
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CN202211340109.0A
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Chinese (zh)
Inventor
苏琪
陈建平
匡世华
饶安梅
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Guizhou Aerospace Tianma Electrical Technology Co Ltd
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Guizhou Aerospace Tianma Electrical Technology Co Ltd
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Priority to CN202211340109.0A priority Critical patent/CN115594818A/en
Publication of CN115594818A publication Critical patent/CN115594818A/en
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    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/65Low-molecular-weight compounds having active hydrogen with high-molecular-weight compounds having active hydrogen
    • C08G18/66Compounds of groups C08G18/42, C08G18/48, or C08G18/52
    • C08G18/6666Compounds of group C08G18/48 or C08G18/52
    • C08G18/667Compounds of group C08G18/48 or C08G18/52 with compounds of group C08G18/32 or polyamines of C08G18/38
    • C08G18/6674Compounds of group C08G18/48 or C08G18/52 with compounds of group C08G18/32 or polyamines of C08G18/38 with compounds of group C08G18/3203
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/30Low-molecular-weight compounds
    • C08G18/32Polyhydroxy compounds; Polyamines; Hydroxyamines
    • C08G18/3203Polyhydroxy compounds
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40High-molecular-weight compounds
    • C08G18/48Polyethers
    • C08G18/4804Two or more polyethers of different physical or chemical nature
    • C08G18/482Mixtures of polyethers containing at least one polyether containing nitrogen
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G2101/00Manufacture of cellular products
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G2110/00Foam properties
    • C08G2110/0025Foam properties rigid

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)

Abstract

The invention belongs to the technical field of high polymer hard polyurethane molding, and particularly relates to a square frame type fragile cover and a preparation method thereof; the frangible lid consists of the following components: 85-90 parts of polyol, 15 parts of polyether polyol, 10-15 parts of phenylenediamine polyether, 5-8 parts of foaming agent, 0.2-0.6 part of aging agent, 0.6-0.8 part of catalyst and 1-1.7 parts of hydrolysis resistance; 130-160 parts of isocyanate. Through the special layer forming method that adopts mould temperature regulator to carry out suitable heating and refrigerated mode and oval type packing ring support net cloth to large-scale complicated component, convenient operation to accurate, the even accuse temperature to the mould has been realized, need not to make the breakable lid product of launch canister (case) fast through many times of shaping process turnover.

Description

Square frame type fragile cover and preparation method thereof
Technical Field
The invention belongs to the technical field of high polymer rigid polyurethane molding, and particularly relates to a square frame type fragile cover and a preparation method thereof.
Background
With the continuous development of polymer composite material technology, a great deal of research on composite material fragile covers is carried out by domestic and foreign scholars, and the research is taken as a key point. As an important component of storage and protection missiles, the structure optimization and forming process of the fragile cover is always the leading trend of launching technology, and in recent years, the rigid polyurethane foam material which is widely applied due to excellent shock resistance and shock resistance, high specific strength and high density is a novel material for manufacturing the fragile cover of the launching box (barrel). Polyurethane foam is used as a high polymer synthetic material, belongs to a pentagonal closed cell structure with high crosslinking degree and regular interior, can be respectively prepared into semi-hard polyurethane, soft polyurethane and other types according to different required product performances and production formulas, is the hard PU technology which takes MDI as a raw material and is successfully developed by ICI companies in the United states at first, is used for plate parts in rocket engines and airplane interlayers, and is popularized to the fields of building decoration, vehicle engineering, ships and the like.
The preparation method of the rigid polyurethane foam comprises a prepolymer method, a semi-prepolymer method and a one-step method. At present, the one-step process is widely applied, the synthesis process of an intermediate is omitted in the foam material produced by the one-step process, raw material purchase and equipment investment are less, the production steps are simpler and more convenient, and the forming of the fragile cover product of the launching tube (box) is powerfully promoted.
Disclosure of Invention
The invention provides a square frame type fragile cover and a preparation method thereof for solving the problems.
The method is realized by the following technical scheme:
1. a square frame type breakable cover is made of white material and isocyanate; the white material consists of 85-90 parts of polyol, 15 parts of polyether polyol, 10-15 parts of phenylenediamine polyether, 5-8 parts of foaming agent, 0.2-0.6 part of aging agent, 0.6-0.8 part of catalyst and 1-1.7 parts of hydrolysis resistant agent; the isocyanate accounts for 130 to 160 parts by weight.
2. The preparation method of the square fragile cover is characterized in that the square fragile cover is prepared by adopting a mode of laying solvent-free mesh cloth.
Further, the preparation method of the fragile cover specifically comprises the following steps:
A. mixing 85-90 parts of polyol and 15 parts of polyether polyol, 10-15 parts of phenylenediamine polyether, 5-8 parts of foaming agent, 0.2-0.6 part of aging agent, 0.6-0.8 part of catalyst and 1-1.7 parts of hydrolysis resistant agent, and stirring and mixing at the speed of 1200-1400 r/min for 5min to obtain a white material;
B. connecting an oil outlet pipeline and an oil return pipeline in a mold temperature regulator with oil temperature pipeline interfaces of an upper mold and a lower mold of a mold respectively, setting the temperature after starting the mold temperature regulator, and circulating heat-conducting silicone oil in a mold oil pipe after the motor pump provides power to drive the heat-conducting silicone oil to be heated;
C. adding the white material into a charging bucket of a high-pressure foaming machine, mixing and stirring the white material as an independent component, taking isocyanate as another component, and fully mixing and stirring the two components for 10-120 s through the high-pressure foaming machine to obtain a combined material;
D. placing an elliptical gasket on the lower die to support a special layering mode of the gridding cloth, and placing the reinforcing cloth into the lower die in advance;
E. pouring the combined material into a mold at the temperature of 25-50 ℃;
F. keeping the mold at a constant temperature of 80-120 ℃ for 1-2 hours;
G. closing the heating function of the mold temperature adjusting machine, respectively connecting a cooling water inlet and a water return interface of the mold temperature adjusting machine with a water inlet and a water outlet of a low-temperature constant-temperature circulating water tank, and uniformly cooling heat-conducting silicone oil in the mold oil pipe after pumping low-temperature water through a motor pump;
H. and demolding to obtain the fragile cap product.
In conclusion, the invention has the beneficial effects that: the invention is prepared by taking polyol and polyether polyol as main raw materials and matching with components such as flame retardant, ultraviolet-resistant absorbent and the like. The frangible cover is used as an important component in a missile launching system, can bear static air pressure within a certain numerical range, and can be opened after being broken by laser waves generated by specific gas flow. In order to overcome the problem that part of large molds cannot be uniformly heated due to the limited size of an oven, a molding method for heating and cooling a complicated component mold is provided, namely, an oil outlet pipeline and an oil return pipeline in a mold temperature regulator are respectively connected with oil temperature pipeline interfaces of an upper mold and a lower mold of the mold through controlling a temperature regulator in a mold temperature regulator, and then temperature setting is carried out, so that the purpose of controlling the temperature of the mold is achieved. The mold temperature adjusting machine is used for carrying out appropriate heating and cooling modes and a special laying layer forming method on the large-scale complex component, the operation is convenient, accurate and uniform temperature control on the mold is realized, and the fragile cover product of the launching tube (box) can be quickly prepared without multiple forming process turnover. In the forming process, the reinforcing cloth is embedded into the polyurethane material in a special laying mode that the elliptical gasket supports the grid cloth, so that the traditional cloth laying process is broken through, and the design problem of the front fragile cover is solved. The large-sized fragile box cover manufactured by adopting the specific layer laying mode of supporting the grid cloth by the oval washer has the advantages of smooth appearance, simple process, convenience in operation, high labor efficiency and convenience in popularization and application in later-stage production.
The fragile cover manufactured by the method is provided with 4 emissive grooves and 1 annular groove, and under a pressure-bearing state, the fragile cover can be structurally damaged and integrally split along the groove region, and the lower cover is split into four parts along the stress weak region under the action of shock wave impact, so that a split fracture state is achieved, and the missile can be rapidly ejected. By means of the process forming mode of laying the reinforced grid cloth, the problems of warping and deformation of the square large-size fragile protective cover after forming are solved, the pressure bearing difference between the non-weak area and the radial cross groove area is enhanced, and the application performance requirement of the large front-end fragile protective cover is met.
Detailed Description
The following is a detailed description of the embodiments of the present invention, but the present invention is not limited to these embodiments, and any modifications or substitutions in the basic spirit of the embodiments are included in the scope of the present invention as claimed in the claims.
Example 1
A. Mixing 87 parts of polyol, 15 parts of polyether polyol, 12 parts of phenylenediamine polyether, 7 parts of foaming agent, 0.4 part of aging agent, 0.7 part of catalyst and 1.5 parts of hydrolysis-resistant agent, and stirring and mixing at 1300r/min for 5min to obtain a white material;
B. connecting an oil outlet pipeline and an oil return pipeline in a mold temperature regulator with oil temperature pipeline interfaces of an upper mold and a lower mold of a mold respectively, setting the temperature after starting the mold temperature regulator, and circulating heat-conducting silicone oil in a mold oil pipe after the heat-conducting silicone oil is heated by the power provided by a motor pump;
C. adding the white material into a charging bucket of a high-pressure foaming machine, mixing and stirring the white material as an independent component, taking 145 parts of isocyanate as another component, and fully mixing and stirring the two components for 60s through the high-pressure foaming machine to obtain a combined material;
D. placing an elliptical gasket on the lower die to support a special layering mode of the gridding cloth, and placing the reinforcing cloth into the lower die in advance;
E. pouring the combined material into a mould at the temperature of 35 ℃;
F. keeping the mold constant at 100 ℃ for 2 hours;
G. and closing the heating function of the mold temperature adjusting machine, connecting the cooling water inlet and return water interface of the mold temperature adjusting machine with the water inlet and outlet of the low-temperature constant-temperature circulating water tank respectively, and pumping low-temperature water through a motor pump to uniformly cool heat-conducting silicone oil in the mold oil pipe.
H. And demolding to obtain the fragile cap product.
Example 2
A. Mixing 85 parts of polyol, 15 parts of polyether polyol, 10 parts of phenylenediamine polyether, 5 parts of foaming agent, 0.2 part of aging agent, 0.6 part of catalyst and 1 part of hydrolysis resistant agent, and stirring and mixing for 5min at the speed of 1200r/min to obtain a white material;
B. connecting an oil outlet pipeline and an oil return pipeline in a mold temperature regulator with oil temperature pipeline interfaces of an upper mold and a lower mold of a mold respectively, setting the temperature after starting the mold temperature regulator, and circulating heat-conducting silicone oil in a mold oil pipe after the heat-conducting silicone oil is heated by the power provided by a motor pump;
C. adding the white material into a charging bucket of a high-pressure foaming machine, mixing and stirring the white material as an independent component, taking 130 parts of isocyanate as another component, and fully mixing and stirring the two components for 30s through the high-pressure foaming machine to obtain a combined material;
D. placing an elliptical gasket on the lower die to support a special layering mode of the gridding cloth, and placing the reinforcing cloth into the lower die in advance;
E. pouring the combined material into a mould at the temperature of 50 ℃;
F. keeping the mold constant at 80 ℃ for 2 hours;
G. closing the heating function of the mold temperature adjusting machine, respectively connecting a cooling water inlet and a water return interface of the mold temperature adjusting machine with a water inlet and a water outlet of a low-temperature constant-temperature circulating water tank, and uniformly cooling heat-conducting silicone oil in the mold oil pipe after pumping low-temperature water through a motor pump;
H. and demolding to obtain the fragile cap product.
Example 3
A. Mixing 90 parts of polyol and 15 parts of polyether polyol, 15 parts of phenylenediamine polyether, 8 parts of foaming agent, 0.6 part of aging agent, 0.8 part of catalyst and 1.7 parts of hydrolysis resistant agent, and stirring and mixing for 5min at the speed of 1400r/min to obtain a white material;
B. connecting an oil outlet pipeline and an oil return pipeline in a mold temperature regulator with oil temperature pipeline interfaces of an upper mold and a lower mold of a mold respectively, setting the temperature after starting the mold temperature regulator, and circulating heat-conducting silicone oil in a mold oil pipe after the motor pump provides power to drive the heat-conducting silicone oil to be heated;
C. adding the white material into a charging bucket of a high-pressure foaming machine, mixing and stirring the white material as an independent component, taking 160 parts of isocyanate as another component, and fully mixing and stirring the two components for 120s through the high-pressure foaming machine to obtain a combined material;
D. placing an elliptical gasket on the lower die to support a special layering mode of the gridding cloth, and placing the reinforcing cloth into the lower die in advance;
E. pouring the combined material into a mould at the temperature of 25 ℃;
F. keeping the mold at a constant temperature of 120 ℃ for 1 hour;
G. closing the heating function of the mold temperature adjusting machine, respectively connecting a cooling water inlet and a water return interface of the mold temperature adjusting machine with a water inlet and a water outlet of a low-temperature constant-temperature circulating water tank, and uniformly cooling heat-conducting silicone oil in the mold oil pipe after pumping low-temperature water through a motor pump;
H. and demolding to obtain the fragile cap product.

Claims (3)

1. A square frame type breakable cover is characterized in that the square frame type breakable cover is made of white materials and isocyanate; the white material consists of 85-90 parts of polyol, 15 parts of polyether polyol, 10-15 parts of phenylenediamine polyether, 5-8 parts of foaming agent, 0.2-0.6 part of aging agent, 0.6-0.8 part of catalyst and 1-1.7 parts of hydrolysis resistant agent; the isocyanate accounts for 130 to 160 parts by weight.
2. The method of claim 1, wherein the frangible cover is formed by layering a solvent-free mesh.
3. A method of making a square frame type frangible lid as claimed in claim 2, comprising the steps of:
A. mixing 85-90 parts of polyol and 15 parts of polyether polyol, 10-15 parts of phenylenediamine polyether and 5-8 parts of foaming agent, and stirring and mixing for 5min at the speed of 1200-1400 r/min to obtain a white material;
B. connecting an oil outlet pipeline and an oil return pipeline in a mold temperature regulator with oil temperature pipeline interfaces of an upper mold and a lower mold of a mold respectively, setting the temperature after starting the mold temperature regulator, and circulating heat-conducting silicone oil in a mold oil pipe after the heat-conducting silicone oil is heated by the power provided by a motor pump;
C. adding the white material into a charging bucket of a high-pressure foaming machine, mixing and stirring the white material as an independent component, taking isocyanate as another component, and fully mixing and stirring the two components for 10-120 s through the high-pressure foaming machine to obtain a combined material;
D. placing an elliptical gasket on the lower die to support a special layering mode of the gridding cloth, and placing the reinforcing cloth into the lower die in advance;
E. pouring the combined material into a mold at the temperature of 25-50 ℃;
F. keeping the mold constant temperature for 1-2 hours at 80-120 ℃;
G. closing the heating function of the mold temperature adjusting machine, respectively connecting a cooling water inlet and a water return interface of the mold temperature adjusting machine with a water inlet and a water outlet of a low-temperature constant-temperature circulating water tank, and uniformly cooling heat-conducting silicone oil in the mold oil pipe after pumping low-temperature water through a motor pump;
H. and demolding to obtain the fragile cap product.
CN202211340109.0A 2022-10-29 2022-10-29 Square frame type fragile cover and preparation method thereof Pending CN115594818A (en)

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Application Number Priority Date Filing Date Title
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Publication Number Publication Date
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201189697Y (en) * 2007-12-28 2009-02-04 中国铝业股份有限公司 Heating control apparatus for carbon anode green pressing vibratory compaction mould
CN202011173U (en) * 2011-01-17 2011-10-19 合肥合锻机床股份有限公司 Mould hot oil circle heating system of interior trim part hydraulic machine of car
CN105017757A (en) * 2015-06-30 2015-11-04 湖北三江航天万峰科技发展有限公司 Method and product used for preparing friable lids
CN106079335A (en) * 2016-08-04 2016-11-09 江苏文光模具技术有限公司 The temperature varied cyclical system of a kind of injection mold and temperature varied cyclical method
CN106956446A (en) * 2017-04-20 2017-07-18 咸宁海威复合材料制品有限公司 The compression molding device and method of a kind of composite
CN114644083A (en) * 2020-12-21 2022-06-21 帕洛阿尔托研究中心公司 Triggerable mechanism and debris containment arrangement for self-destructing frangible structures and sealed receptacles
CN114970251A (en) * 2022-05-12 2022-08-30 山东非金属材料研究所 Design and manufacturing method of composite material frangible cover

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201189697Y (en) * 2007-12-28 2009-02-04 中国铝业股份有限公司 Heating control apparatus for carbon anode green pressing vibratory compaction mould
CN202011173U (en) * 2011-01-17 2011-10-19 合肥合锻机床股份有限公司 Mould hot oil circle heating system of interior trim part hydraulic machine of car
CN105017757A (en) * 2015-06-30 2015-11-04 湖北三江航天万峰科技发展有限公司 Method and product used for preparing friable lids
CN106079335A (en) * 2016-08-04 2016-11-09 江苏文光模具技术有限公司 The temperature varied cyclical system of a kind of injection mold and temperature varied cyclical method
CN106956446A (en) * 2017-04-20 2017-07-18 咸宁海威复合材料制品有限公司 The compression molding device and method of a kind of composite
CN114644083A (en) * 2020-12-21 2022-06-21 帕洛阿尔托研究中心公司 Triggerable mechanism and debris containment arrangement for self-destructing frangible structures and sealed receptacles
CN114970251A (en) * 2022-05-12 2022-08-30 山东非金属材料研究所 Design and manufacturing method of composite material frangible cover

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