CN108264768A - A kind of halogen-free fire-resistant engineering plastics polysulfones - Google Patents

Abstract

The invention discloses a halogen-free flame-retardant engineering plastic polysulfone, which comprises the following components in weight percentage: polysulfone 45-60%, glass fiber 15-30%, branched polyphosphonate flame retardant 10-30% , melamine-based flame retardant 0‑28%, antioxidant 0.2‑0.6%, anti-dripping agent 0.2‑0.5%, lubricant 0.5‑0.8% and silane coupling agent 0.2‑0.4%. The present invention introduces a branched polyphosphonate halogen-free flame retardant with a softening point of 90-110°C in the engineering plastic polysulfone (PSU) formula, due to the molecular structure of the branched polyphosphonate halogen-free flame retardant Similar to polysulfone, it has a large molecular weight and is not easy to migrate. It can achieve good flame retardant effect with melamine flame retardant, and its flame retardancy can reach UL94 V‑0 level.

Description

A kind of halogen-free flame-retardant engineering plastic polysulfone

technical field

The invention belongs to the technical field of polymer materials, and in particular relates to a halogen-free flame-retardant engineering plastic polysulfone (PSU).

Background technique

Polysulfone (PSU) is a thermoplastic engineering plastic with excellent mechanical properties, high rigidity, wear resistance, radiation resistance, hydrolysis resistance, high strength, high thermal stability and self-extinguishing properties, and the processed products have good dimensional stability and are easy to mold. Small shrinkage, excellent electrical properties and good chemical stability in a wide temperature range. Therefore, it has been widely used in the fields of electronic appliances, mechanical processing, automobiles, medical appliances, food processing and non-stick coatings for a long time. However, compared with other polysulfone resins, the flame retardancy of PSU is not ideal. According to the UL94 standard, general-purpose polysulfone (PSU) only reaches HB grade. In order to improve the flame retardancy of polysulfone (PSU), it is usually processed Add brominated flame retardant and antimony trioxide in the process. For example, adding 0.5% brominated polyphenylene ether with a molecular weight of 5000 and a small amount of stabilizer to polysulfone can obtain a material with a flame retardancy of V-0; another example, adding 4 to 14 parts to 100 parts of polysulfone resin Hexabromodiphenyl ether and 1.5 to 4 parts of antimony trioxide are melted and granulated to produce a resin with an oxygen index of 38 to 40 and a flame retardancy of UL94V-0.

With the increasing requirements of environmental protection and EU RoHS and REACH certification requirements, the traditional antimony trioxide and bromine flame retardants can no longer meet the market demand due to factors such as non-migration resistance and environmental protection. Therefore, the development of halogen-free flame-retardant polymer Sulfone (PSU) is urgent.

Contents of the invention

The invention provides a halogen-free flame-retardant engineering plastic polysulfone, which introduces a branched polyphosphonate flame retardant. The flame retardant has a molecular structure similar to that of polysulfone, has a large molecular weight, is difficult to migrate, and has a good flame-retardant effect.

The technical solution adopted in the present invention is: a halogen-free flame-retardant engineering plastic polysulfone, comprising the following components by weight percentage:

The halogen-free flame-retardant engineering plastic polysulfone (PSU) of the present invention mainly includes the following components:

Polysulfone (PSU): The selected polysulfone (PSU) is synthesized by polycondensation of bisphenol A and 4,4'-dichlorodiphenyl sulfone. The brands sold on the market include S2010, S3010, and S6010 of BASF in Germany, and Soviet Union in the United States. Granville's P-1700 accounts for about 45-60% of the formula;

Glass fiber: long glass fiber is used, and the dosage in the formula is 15-30%;

Branched polyphosphonate halogen-free flame retardant: the dosage is 10-30% in the formula,

Preferably, the branched polyphosphonate flame retardant is selected from one or both of the compounds of formula (I) (flame retardant C-1) and formula (II) (flame retardant C-2). kind,

Wherein, n=20-60, m=1-5, k=1-20.

The main difference between flame retardant C-1 and C-2 is that the branching agent used in the synthesis process is different. The former uses 1,1,1-tris(4-hydroxyphenyl)ethane, and the latter uses triphenyl phosphate ( TPP) is synthesized by the principle of transesterification and polycondensation of bisphenol A and diphenyl methylphosphonate under the catalysis of sodium phenate. The reaction formula is as follows:

Preferably, the preparation method of the branched polyphosphonate flame retardant is: under the protection of inert gas, bisphenol A, diphenyl methyl phosphonate, catalyst sodium phenate and branching agent are mixed at 250-300 °C , heat preservation and reaction for 8-9 hours to obtain a crude polymer product, which is then cooled with water, pulverized, filtered, and vacuum-dried to obtain a branched polyphosphonate flame retardant.

Preferably, the molar ratio of bisphenol A, diphenyl methylphosphonate and branching agent is 0.1-0.3:0.1-0.2:0.001-0.005.

Preferably, the branching agent is 1,1,1-tris(4-hydroxyphenyl)ethane or triphenyl phosphate; the inert gas is one or both of nitrogen and carbon dioxide.

Preferably, the melamine-based flame retardant is one or more of melamine pyrophosphate, melamine polyphosphate and melamine cyanurate. More preferably, the melamine-based flame retardant is melamine cyanurate (MC).

Preferably, the antioxidant is obtained by compounding antioxidant B215 and antioxidant 1098 at a mass ratio of 1:1.

Preferably, the anti-dripping agent is one or both of polytetrafluoroethylene (PTFE) and nano-montmorillonite. More preferably, the anti-dripping agent is polytetrafluoroethylene (PTFE).

Preferably, the lubricant is obtained by compounding the internal lubricant PETS and the external lubricant EBS at a mass ratio of 5:2.

Preferably, the silane coupling agent is KH550.

The processing equipment used is a twin-screw extruder, and under the premise of ensuring uniform mixing, select as low as possible processing temperature, low shear force, short residence time and other mild processing conditions.

The phosphorus content of the prepared halogen-free flame-retardant engineering plastic polysulfone is 1-5%.

The beneficial effects of the present invention are: the present invention introduces a branched polyphosphonate halogen-free flame retardant with a softening point of 90-110°C in the engineering plastic polysulfone (PSU) formula, because the branched polyphosphonate The molecular structure of the halogenated flame retardant is similar to that of polysulfone, the molecular weight is large, and it is not easy to migrate. It can obtain a good flame retardant effect when combined with a melamine flame retardant, and the flame retardancy can reach UL94V-0 level.

Detailed ways

The present invention will be further described below in conjunction with the examples, but not limited thereto.

Example 1

This example is the synthesis of flame retardant C-1.

Drop into 34.2g bisphenol A (0.15mol), 40.1g diphenyl methylphosphonate (content 95%, 0.1534mol), 6mg sodium phenoxide (NaOPh) in the 250mL three-necked flask that distillation column and mechanical stirrer are equipped Catalyst, 0.46g branching agent 1,1,1-three (4-hydroxyphenyl) ethane (0.0015mol), pass into nitrogen and air is discharged, vacuumize, oil bath heating, this reaction mixture is from under vacuum Heat from 250°C to 300°C, keep warm for 8-9 hours, collect about 35g of distillate during the reaction, and observe a significant and rapid increase in the solution viscosity of the melt in the last 1 hour of the reaction, end the reaction, and polymerize The water-cooled powder is fine and vacuum-dried to obtain flame retardant C-1, which contains 10.8% phosphorus and has a Tg of 102°C.

Example 2

This example is the synthesis of flame retardant C-2.

Drop into 34.2g bisphenol A (0.15mol), 40.1g diphenyl methylphosphonate (content is 95%, 0.1534mol), 6mg sodium phenoxide (NaOPh ) catalyzer, 0.49g branching agent triphenyl phosphate (TPP) (0.0015mol), pass into nitrogen and air is discharged, vacuumize, oil bath heating, this reaction mixture is heated from 250 ℃ to 300 ℃ under vacuum, insulation React for 8-9 hours, collect about 35g of distillate during the reaction, and observe that the solution viscosity of the melt increases significantly and rapidly in the last 1 hour of the reaction. The reaction is terminated, and the polymer water-cooled powder is finely ground and vacuum-dried to obtain Flame retardant C-2, the phosphorus content of the flame retardant is 10.9%, and the Tg is 92°C.

Example 3 - Example 9

According to the formula shown in Table 1, each raw material is pre-dried to a water content of less than 0.5%, mixed evenly, put into a twin-screw extruder, mixed and extruded at 300°C to obtain a halogen-free flame-retardant Engineering plastic polysulfone (PSU). The product was made into 3.2mm and 1.6mm thick sample strips, and the flame retardancy was measured by the UL94 vertical combustion method, and the phosphorus content of the product was measured. The test results are shown in Table 1.

Table 1 Example 3-9 halogen-free flame-retardant engineering plastics polysulfone (PSU) formulation and flame-retardant test results (formulation is weight percentage)

Claims (10)

1. a kind of halogen-free fire-resistant engineering plastics polysulfones, which is characterized in that including following components in percentage by weight：

2. halogen-free fire-resistant engineering plastics polysulfones according to claim 1, which is characterized in that the branched polyphosphonates are fire-retardant Agent is selected from one kind or two kinds in the compound of formula (I) and formula (II),

Wherein, n=20-60, m=1-5, k=1-10.

3. halogen-free fire-resistant engineering plastics polysulfones according to claim 1 or 2, which is characterized in that the branched polyphosphonates The preparation method of fire retardant is：Under inert gas shielding, by bisphenol-A, diphenyl methylphosphonate, catalyst phenol sodium and branched Agent is at 250-300 DEG C, and insulation reaction 8-9 hours obtains polymer crude product, then is water-cooled, crushes, filters, is dried in vacuo, i.e., Branched polyphosphonates fire retardant can be made.

4. halogen-free fire-resistant engineering plastics polysulfones according to claim 3, which is characterized in that the bisphenol-A, methylphosphonic acid two The molar ratio of phenyl ester and branching agent is 0.1-0.3:0.1-0.2:0.001-0.005.

5. halogen-free fire-resistant engineering plastics polysulfones according to claim 3, which is characterized in that the branching agent is 1,1,1- tri- (4- hydroxyphenyls) ethane or triphenyl phosphate；The inert gas is one or both of nitrogen and carbon dioxide.

6. halogen-free fire-resistant engineering plastics polysulfones according to claim 1, which is characterized in that the melamine based flame retardant For one or more of melamine pyrophosphate, polyphosphoric acid melamine and melamine cyanurate.

7. halogen-free fire-resistant engineering plastics polysulfones according to claim 1, which is characterized in that the antioxidant is by anti-oxidant Agent B215 and antioxidant 1098 are with 1:1 mass ratio is compounded and is obtained.

8. halogen-free fire-resistant engineering plastics polysulfones according to claim 1, which is characterized in that the anti-dripping agent is polytetrafluoro One or both of ethylene and nano imvite.

9. halogen-free fire-resistant engineering plastics polysulfones according to claim 1, which is characterized in that the lubricant is by in-lubricant PETS and external lubricant EBS are with 1-6:1 mass ratio is compounded and is obtained.

10. halogen-free fire-resistant engineering plastics polysulfones according to claim 1, which is characterized in that the silane coupling agent is KH550。