PET (Polyethylene Terephthalate) flame-retardant material, preparation method and preparation method of floor containing PET flame-retardant material

Abstract

The invention discloses a novel PET (Polyethylene Terephthalate) flame-retardant material and a preparation method thereof. The flame-retardant material is prepared from the following components in parts by weight: 50 to 55 parts of PET resin, 4.0 to 6.0 parts of decabromodiphenyl ethane, 4.0 to 6.0 parts of ammonium polyphosphate, 1.0 to 2.0 parts of composite nucleating agent, 2.0 to 4.0 parts of plasticizer, 30 to 35 parts of chopped glass fiber, 0.5 to 1.0 part of lubricant and 0.3 to 0.5 part of antioxidant. According to the novel PET flame-retardant material, the ammonium polyphosphate (APP) and the decabromodiphenyl ethane (DBDPE) are adopted to form a synergistic flame-retardant system, the APP is an acid source, the DBDPE is a gas source, and the APP and the DBDPE synergistically generate an expanded carbon layer so as to improve the flame-retardant property.

Description

Technical Field

[0001] The invention relates to the technical field of flame retardant materials, and in particular to a novel PET flame retardant material and a preparation method thereof. Background Art

[0002] Polyethylene terephthalate (PET) is an important thermoplastic polyester material with excellent physical properties, chemical stability, high and low temperature resistance, environmental protection, electrical insulation, and little temperature influence. Therefore, PET materials are often used in the field of electronic equipment and have also become an ideal material for making floors. However, PET is a flammable material, which poses a great safety hazard to the widespread application of PET floors. Additive flame retardants are mainly used to prepare PET flame retardant materials in industry. By adding a large proportion of flame retardants, the flame retardant properties of the composite material can be effectively improved, but the mechanical properties of the material will also decrease. Therefore, it is necessary to develop a new type of flame retardant material that can suppress the problem of decreased impact strength while ensuring the flame retardant effect.

[0003] Defects and shortcomings of the prior art: 1. The most common method is to improve the flame retardant properties of PET by adding small molecule compound flame retardants to the PET matrix. However, the addition of flame retardants may affect the processing properties and mechanical properties of the material, and may also affect the appearance quality of the product and the durability of the flame retardant effect. Therefore, improvement is needed. 2. By introducing a reactive flame retardant containing flame retardant elements such as phosphorus and nitrogen as a third monomer during the PET polymerization process, it is combined with the main chain of the molecule to achieve a flame retardant effect. The PET prepared by this method has permanent flame retardant properties, but the process flow of PET polymerization production needs to be changed, which is costly. 3. By introducing self-crosslinkable functional groups into the PET molecular chain, the polymer molecules are rearranged at high temperature to promote carbonization of the material and achieve flame retardancy and anti-melting droplet resistance. This method can achieve flame retardancy without melting droplets, and does not contain any traditional flame retardant elements (such as Cl, Br, P, etc.), providing a new method for new green flame retardant technology, but its process is complicated and the cost is high. Summary of the invention

[0004] In order to solve the above technical problems, the novel PET flame retardant material of the present invention adopts ammonium polyphosphate (APP) and decabromodiphenylethane (DBDPE) to form a synergistic flame retardant system, wherein APP is an acid source and DBDPE is a gas source, and the two synergistically produce an expanded carbon layer to improve the flame retardant performance.

[0005] To solve the above technical problems, a technical solution adopted by the present invention is: the present invention provides a new PET flame retardant material, which includes the following components in parts by weight: 50-55 parts of PET resin, 4.0-6.0 parts of decabromodiphenyl ethane (DBDPE), 4.0-6.0 parts of ammonium polyphosphate (APP), 1.0-2.0 parts of composite nucleating agent, 2.0-4.0 parts of plasticizer, 30-35 parts of chopped glass fiber, 0.5-1.0 parts of lubricant and 0.3-0.5 parts of antioxidant.

[0006] Furthermore, the composite nucleating agent is T8 cage-type oligomeric silsesquioxane (POSS).

[0007] Furthermore, the plasticizer is one of diacetyl monoacylglycerol, phenyltetralin butane (PTB), pentaerythritol diethylene glycol C5-9 acid alcohol and diethylene glycol C5-9 benzoic acid acid ester.

[0008] Furthermore, the lubricant is a combination of one or more of pentaerythritol stearate (PETS) and polysiloxane.

[0009] Furthermore, the antioxidant is one of 2,6-di-tert-butyl-4-methylphenol (BHT) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1010).

[0010] Furthermore, the fiber diameter of the chopped glass fibers is 9-13 μm, and the moisture content is ≤0.1%.

[0011] The present invention also provides a method for preparing the novel PET flame retardant material, comprising the following steps:

[0012] Step 1. First, decabromodiphenylethane and ammonium polyphosphate are added to the mixer together with polyvinyl chloride according to the weight ratio and mixed thoroughly. The mixer speed is set at 250-350r / min. After the raw materials in the mixer are mixed for 8 minutes, the composite nucleating agent, plasticizer, antioxidant, lubricant and short glass fiber are added to the mixer in turn according to the weight ratio, and mixed and stirred for 10-20 minutes to finally obtain a mixed powder;

[0013] Step 2. Add the mixed powder obtained in step 1 to the twin-screw extruder, and set the temperature from the feeding port of the twin-screw extruder to the die head to four sections, which are set to 195-205°C, 220-235°C, 240-254°C and 255-265°C, respectively, for melt blending and extrusion;

[0014] Step 3. After extrusion, granulation and cooling, a flame retardant enhanced PET new flame retardant material is obtained.

[0015] The present invention further provides a method for preparing a floor using the novel PET flame-retardant material, which also includes the following steps: Step 4. Adding the flame-retardant and enhanced PET novel flame-retardant material prepared in Step 3 into an injection molding machine for injection molding into a flame-retardant and enhanced PET floor.

[0016] The beneficial effects of the present invention are:

[0017] Because the intumescent flame retardant (IFR) is a highly efficient and environmentally friendly flame retardant material, it achieves a flame retardant effect by forming an expanded carbon layer when the material burns. This carbon layer can isolate oxygen and heat, thereby preventing the spread of flames. Among them, the acid source is a key component. After being decomposed by heat, it produces an acid catalyst, which promotes the dehydrogenation of the polymer into carbon. At the same time, the acidic viscous substance covering the surface of the condensed phase can play a role in preventing heat and mass transfer. The gas generated by the decomposition of the gas source during combustion acts on the carbonized material to form a closed, porous, and fluffy foamed structure carbon layer. Therefore, the new PET flame retardant material of the present invention adopts ammonium polyphosphate (APP) and decabromodiphenyl ethane (DBDPE) to form a synergistic flame retardant system, wherein APP is the acid source and DBDPE is the gas source, and the two synergistically produce an expanded carbon layer to improve flame retardant properties;

[0018] The novel PET flame-retardant material of the present invention adopts chopped glass fibers with a fiber diameter of 9-13 μm and a moisture content of ≤0.1%. The chopped glass fibers have excellent dry fluidity, are very advantageous for continuous feeding, and are evenly distributed in the product. The PET novel flame-retardant material has excellent wet dispersibility and is easily impregnated with resin when preparing the flame-retardant material, thereby ultimately enhancing the mechanical strength and plasticity of the flame-retardant material.

[0019] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail as follows. DETAILED DESCRIPTION

[0020] The following is a specific embodiment of the present invention, and those skilled in the art can easily understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented in other different ways, that is, different modifications and changes can be made without departing from the scope disclosed by the present invention.

[0021] Example 1: A method for preparing a floor using PET flame retardant material:

[0022] Step 1. First, add 4 parts of decabromodiphenylethane, 4 parts of ammonium polyphosphate and 50 parts of polyvinyl chloride into a mixer and mix them thoroughly. The mixer speed is set at 300r / min. After the raw materials in the mixer are mixed for 8 minutes, 1 part of a composite nucleating agent, 2 parts of a plasticizer, 0.3 parts of an antioxidant, 0.5 parts of a lubricant, and 30 parts of short glass fibers (with a fiber diameter of 9 μm and a moisture content of ≤0.1%) are added to the mixer in sequence, and mixed and stirred for 15 minutes to finally obtain a mixed powder for preparing a PET floor substrate.

[0023] Step 2. Add the mixed powder obtained in step 1 into a twin-screw extruder, and set the temperature from the feeding port to the die of the twin-screw extruder to four stages, which are set to 200°C, 230°C, 250°C, and 260°C in sequence for melt blending and extrusion.

[0024] Step 3. After extrusion, granulation and cooling, a flame-retardant and reinforced PET floor substrate is obtained.

[0025] Step 4. Add the flame retardant reinforced PET floor substrate prepared in step 3 into an injection molding machine for injection molding into a flame retardant reinforced PET floor.

[0026] Embodiment 2:

[0027] The preparation method of a floor using PET flame retardant material provided in Example 2 is basically the same as that in Example 1, except that the amounts of decabromodiphenylethane and ammonium polyphosphate are changed to 1 part and 3 parts respectively; the fiber diameter of the short glass fiber is 13 μm, and the moisture content is 0.08%.

[0028] Embodiment 3:

[0029] The preparation method of a floor using PET flame retardant material provided in Example 3 is basically the same as that in Example 1, except that the amounts of decabromodiphenylethane and ammonium polyphosphate are changed to 3 parts and 2 parts respectively; the fiber diameter of the short glass fiber is 11 μm, and the moisture content is 0.06%.

[0030] Embodiment 4:

[0031] The preparation method of a floor using PET flame retardant material provided in Example 4 is basically the same as that in Example 1, except that the amounts of PET resin, decabromodiphenylethane, ammonium polyphosphate, composite nucleating agent, plasticizer, chopped glass fiber, lubricant and antioxidant are adjusted to 55 parts, 6 parts, 6 parts, 2 parts, 4 parts, 35 parts, 1 part and 0.5 parts respectively.

[0032] Embodiment 5:

[0033] The preparation method of a floor using PET flame retardant material provided in Example 5 is basically the same as that in Example 1, except that the amounts of PET resin, decabromodiphenylethane, ammonium polyphosphate, composite nucleating agent, plasticizer, chopped glass fiber, lubricant and antioxidant are adjusted to 52 parts, 5 parts, 5 parts, 1.5 parts, 3 parts, 32 parts, 0.7 parts and 0.4 parts respectively.

[0034] Comparative Example 1: A method for preparing a PET flame-retardant floor:

[0035] Step 1. First, add 4 parts of bromine-containing triphosphate (TDBPPE) and 50 parts of polyvinyl chloride into a mixer and mix them thoroughly. The mixer speed is set at 300r / min. After the raw materials in the mixer are mixed for 8 minutes, 1 part of a composite nucleating agent, 2 parts of a plasticizer, 0.3 parts of an antioxidant, 0.5 parts of a lubricant, and 30 parts of short glass fibers are added to the mixer in sequence. Mix and stir for 15 minutes to finally obtain a mixed powder for preparing a PET floor substrate.

[0036] Step 2. Add the mixed powder obtained in step 1 into a twin-screw extruder, and set the temperature from the feeding port to the die of the twin-screw extruder to four stages, which are set to 200°C, 230°C, 250°C, and 260°C in sequence for melt blending and extrusion.

[0037] Step 3. After extrusion, granulation and cooling, a PET floor substrate with enhanced flame retardancy is obtained.

[0038] Step 4. Add the flame retardant enhanced PET floor substrate prepared in step 3 into an injection molding machine for injection molding into a flame retardant enhanced PET floor.

[0039] Performance evaluation method and implementation standard: After the materials prepared in the above embodiments and comparative examples are dried, they are added to an injection molding machine for injection molding into test specimens. The limiting oxygen index is tested according to GB / T 2406.2-2009 standard. The limiting oxygen index (LOl) refers to the minimum oxygen concentration required for the material to burn in a mixed gas of oxygen and nitrogen under specified conditions. It is generally expressed as the volume percentage of oxygen. The higher the LOl of the material tested, the better its flame retardant performance; the impact strength is tested according to GB-T1843-2008 standard. The impact strength refers to the resistance of the material when subjected to an impact load. The higher the impact strength of the material tested, the more impact-resistant and tougher it is. The results of the above tests are shown in Table 1.

[0040] Table 1

[0041] project Test conditions Limiting oxygen index (%) <![CDATA[Impact strength (kJ / m 2 )]]> Example 1 23℃ 34.5 7.5 Example 2 23℃ 31.9 8.9 Example 3 23℃ 30.5 8.0 Example 4 23℃ 36.0 8.1 Example 5 23℃ 35.1 7.9 Comparative Example 1 23℃ 25.8 5.1

[0042] From the performance test results of Examples 1-5 and Comparative Example 1, it can be seen that the limiting oxygen index and impact strength of the flame retardant material prepared by adding the compounded intumescent flame retardant to the PET resin (Examples 1-5) are higher than those of the flame retardant material prepared by adding a simple additive flame retardant (Comparative Example 1), which indicates that the use of the compounded intumescent flame retardant improves the flame retardancy and toughness of the polyvinyl chloride sheet, and the prepared PET sheet has good flame retardancy and good toughness.

[0043] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A new type of PET flame retardant material, characterized in that: The flame retardant material comprises the following components in parts by weight: 50-55 parts of PET resin, 4.0-6.0 parts of decabromodiphenylethane, 4.0-6.0 parts of ammonium polyphosphate, 1.0-2.0 parts of composite nucleating agent, 2.0-4.0 parts of plasticizer, 30-35 parts of chopped glass fiber, 0.5-1.0 parts of lubricant and 0.3-0.5 parts of antioxidant.

2. The novel PET flame retardant material according to claim 1, characterized in that: The composite nucleating agent is T8 cage-type oligomeric silsesquioxane.

3. The novel PET flame retardant material according to claim 1, characterized in that: The plasticizer is one of diacetyl monoacylglycerol, benzene tetralin butane, pentaerythritol diethylene glycol C5-9 acid alcohol and diethylene glycol benzoic acid C5-9 acid ester.

4. The novel PET flame retardant material according to claim 1, characterized in that: The lubricant is a combination of one or more of pentaerythritol stearate and polysiloxane.

5. The novel PET flame retardant material according to claim 1, characterized in that: The antioxidant is one of 2,6-di-tert-butyl-4-methylphenol and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

6. The novel PET flame retardant material according to claim 1, characterized in that: The fiber diameter of the chopped glass fibers is 9-13 μm, and the moisture content is ≤0.1%.

7. A method for preparing the novel PET flame retardant material according to claim 1, characterized in that: The steps include: Step 1. First, decabromodiphenylethane and ammonium polyphosphate are added to the mixer together with polyvinyl chloride according to the weight ratio and mixed thoroughly. The mixer speed is set at 250-350r / min. After the raw materials in the mixer are mixed for 8 minutes, the composite nucleating agent, plasticizer, antioxidant, lubricant and short glass fiber are added to the mixer in turn according to the weight ratio, and mixed and stirred for 10-20 minutes to finally obtain a mixed powder; Step 2. Add the mixed powder obtained in step 1 to the twin-screw extruder, and set the temperature from the feeding port of the twin-screw extruder to the die head to four sections, which are set to 195-205°C, 220-235°C, 240-254°C and 255-265°C, respectively, for melt blending and extrusion; Step 3. After extrusion, granulation and cooling, a flame retardant enhanced PET new flame retardant material is obtained.

8. A method for preparing a floor using the novel PET flame retardant material according to claim 7, characterized in that: The following steps are also included: Step 4. Add the flame-retardant reinforced PET novel flame-retardant material prepared in step 3 into an injection molding machine and injection mold it into a flame-retardant reinforced PET floor.