Unsaturated polyester bulk molding compound as well as method and application thereof

Abstract

The invention relates to the technical field of a bulk molding compound for metal bonding, and specifically relates to an unsaturated polyester bulk molding compound as well as a method and application of the bulk molding compound. The bulk molding compound is prepared from the following raw materials in parts by weight: 8-20 parts of unsaturated polyester, 5-15 parts of low shrink agent, 55-70 parts of inorganic filler, 0.8-1.8 parts of internal demolding agent, 6-20 parts of fiber-reinforced material, 0.3-0.7 parts of curing agent, 0-3 parts of styrene, and 0.05-0.3 part of coupling agent. According to the invention, after the bulk molding compound (BMC) is molded, fast setting is realized and the appearance is excellent; and when used for electric tool and motor loop sealing and other fields, the bulk molding compound has excellent bonding property and torsion to the metal surface at normal temperature and high temperature, excellent resistance to impact, and excellent voltage withstand performance, conforms to the reliability required by product use, and fills up the blank of the field.

Description

[technical field]

[0001] The invention relates to the technical field of bulk molding compound for metal adhesion, in particular to an unsaturated polyester bulk molding compound and its method and application. [Background technique]

[0002] Originally, the sealing of electrical motors, solenoid valve coils and electric tools was realized by covering steel plates and insulating varnishes. In recent decades, unsaturated polyester bulk molding compound (BMC) has been used for sealing, with an integrated Processing, reducing man-hours, and reducing costs while taking advantage of the good insulation, voltage resistance, and heat resistance of thermosetting molding materials have gradually been widely used in the above fields and become the mainstream.

[0003] Bulk molding compound (BMC) has gradually become the mainstream in the above fields, but general BMC still has insufficient adhesion on the surface of metal and steel, and is easy to peel off, which affects performance a...

Examples

Synthetic example 1

[0038] Synthesis Example 1: In a device with stirring and heating, in a device with nitrogen protection and temperature indication, put in 100 moles of propylene glycol, 50 moles of isophthalic acid, and 50 moles of maleic anhydride, according to the normal reaction method React at 190-210°C until the acid value is below 40, then cool down to 160°C, pour into a solution containing diallyl phthalate and 250ppm hydroquinone for dilution, and keep the dilution temperature at 60-80°C , to obtain an unsaturated polyester A with an acid value of 20 or less and a solid content of 70%. The heat distortion temperature of the molded resin body of A was 146°C.

Synthetic example 2

[0039] Synthesis Example 2: In a device with stirring and heating, pass into a device with nitrogen protection and temperature display, drop in 25 moles of propylene glycol, 75 moles of neopentyl glycol, 60 moles of maleic anhydride, and phthalic anhydride 40 moles, according to the normal reaction method, react at 190~210℃ until the acid value is below 40, then cool down to 160℃, pour into a solution containing styrene and 250ppm hydroquinone for dilution, and keep the dilution temperature at 60~ 80°C, an unsaturated polyester B with an acid value of 25 or less and a solid content of 67% was obtained. The thermal deformation temperature of the molded resin body of B was 132°C.

Embodiment 1～8

[0041] The formula ingredients shown in Table 1 are added to the double-wrist kneader according to the specific ratio, and the temperature of the kneader jacket is kept at 30 ° C. Add resin, styrene, curing agent, low shrinkage agent and filler in order. During the kneading process During the process, the adhered materials on the container wall should be cleaned continuously, and the materials around the blades and the dead corners around the machine should be cleaned in time. After about 30 to 40 minutes of full mixing and uniformity, slowly add the chopped glass fiber in a predetermined proportion. , take it out after fully kneading, place it in a special bag that can prevent the volatilization of cross-linking monomers such as styrene and seal the package, and then you can get the BMC material designed according to the predetermined ratio.

[0042] The bulk molding compound BMC obtained as a trial was evaluated for molding appearance, mold release, mechanical strength at roo...

[technical field]

[0001] The invention relates to the technical field of bulk molding compound for metal adhesion, in particular to an unsaturated polyester bulk molding compound and its method and application. [Background technique]

[0002] Originally, the sealing of electrical motors, solenoid valve coils and electric tools was realized by covering steel plates and insulating varnishes. In recent decades, unsaturated polyester bulk molding compound (BMC) has been used for sealing, with an integrated Processing, reducing man-hours, and reducing costs while taking advantage of the good insulation, voltage resistance, and heat resistance of thermosetting molding materials have gradually been widely used in the above fields and become the mainstream.

[0003] Bulk molding compound (BMC) has gradually become the mainstream in the above fields, but general BMC still has insufficient adhesion on the surface of metal and steel, and is easy to peel off, which affects performance a...

Examples

Synthetic example 1

[0038] Synthesis Example 1: In a device with stirring and heating, in a device with nitrogen protection and temperature indication, put in 100 moles of propylene glycol, 50 moles of isophthalic acid, and 50 moles of maleic anhydride, according to the normal reaction method React at 190-210°C until the acid value is below 40, then cool down to 160°C, pour into a solution containing diallyl phthalate and 250ppm hydroquinone for dilution, and keep the dilution temperature at 60-80°C , to obtain an unsaturated polyester A with an acid value of 20 or less and a solid content of 70%. The heat distortion temperature of the molded resin body of A was 146°C.

Synthetic example 2

[0039] Synthesis Example 2: In a device with stirring and heating, pass into a device with nitrogen protection and temperature display, drop in 25 moles of propylene glycol, 75 moles of neopentyl glycol, 60 moles of maleic anhydride, and phthalic anhydride 40 moles, according to the normal reaction method, react at 190~210℃ until the acid value is below 40, then cool down to 160℃, pour into a solution containing styrene and 250ppm hydroquinone for dilution, and keep the dilution temperature at 60~ 80°C, an unsaturated polyester B with an acid value of 25 or less and a solid content of 67% was obtained. The thermal deformation temperature of the molded resin body of B was 132°C.

Embodiment 1～8

[0041] The formula ingredients shown in Table 1 are added to the double-wrist kneader according to the specific ratio, and the temperature of the kneader jacket is kept at 30 ° C. Add resin, styrene, curing agent, low shrinkage agent and filler in order. During the kneading process During the process, the adhered materials on the container wall should be cleaned continuously, and the materials around the blades and the dead corners around the machine should be cleaned in time. After about 30 to 40 minutes of full mixing and uniformity, slowly add the chopped glass fiber in a predetermined proportion. , take it out after fully kneading, place it in a special bag that can prevent the volatilization of cross-linking monomers such as styrene and seal the package, and then you can get the BMC material designed according to the predetermined ratio.

[0042] The bulk molding compound BMC obtained as a trial was evaluated for molding appearance, mold release, mechanical strength at roo...

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