Powder for manufacturing glass fiber-reinforced polyester, and preparation method therefor

Abstract

The present application discloses a powder for manufacturing a glass fiber-reinforced polyester, and a preparation method for the powder. The powder for manufacturing a glass fiber-reinforced polyester comprises the following components: 50-80 parts of polyester resin, 4-8 parts of a curing agent, 1-2 parts of a leveling agent, 1-2 parts of a degassing agent, and 10-40 parts of a filler, wherein each component is in powdered form, and the polyester resin is implemented as a solid saturated carboxyl polyester having a single-bond structure.

Description

Powder for making polyester glass fiber reinforced plastic and preparation method thereof Technical Field

[0001] The invention relates to the field of polyester glass fiber reinforced plastic materials, and in particular to a powder for making polyester glass fiber reinforced plastic and a preparation method thereof. Background Art

[0002] Currently, the polyester fiberglass currently available on the market is primarily used in the construction, industrial, and chemical sectors, such as doors and windows, fences, cooling towers, corrugated panels, storage tanks, pipelines, and other outdoor applications. It boasts advantages such as lightness, high strength, and corrosion resistance. Polyester fiberglass is primarily manufactured through a pultrusion process using unsaturated polyester, a curing agent, additives, and glass fiber. The resin, curing agent, and additives used are all liquids. The pultrusion process uses resin as the matrix material and fibers and fabrics as reinforcements. Under external traction, the process undergoes impregnation, preforming, and hot-molding curing to form a continuous, regular-section product.

[0003] However, the polyester fiberglass materials produced by the existing pultrusion process have poor weather resistance and are prone to yellowing and aging due to the double-bond structure of the unsaturated polyester resin used. If used in outdoor environments, they still need to be covered with a layer of paint for protection and require regular maintenance.

[0004] Furthermore, most unsaturated polyester resins used in traditional polyester FRPs have poor heat resistance, causing thermal deformation at temperatures between 50°C and 60°C. The resulting polyester FRPs typically only have a heat resistance of 60°C, limiting their potential applications. Furthermore, unsaturated polyesters are rarely used in the production of polyester FRPs, as they offer superior heat resistance and mechanical properties compared to saturated polyesters.

[0005] Summary of the Invention

[0006] One advantage of the present invention is that it provides a powder for making polyester glass reinforced plastics and a preparation method thereof, wherein the powder for making polyester glass reinforced plastics is made of powder material rather than liquid material, and during the production, the powder is first coated on the preheated fabric to cover the powder, and then the polyester glass is formed through a curing and molding process, so that the finally formed polyester glass reinforced plastics can have good performance.

[0007] In order to achieve the above advantages, the present invention provides a powder for making polyester glass fiber reinforced plastics, wherein the powder for making polyester glass fiber reinforced plastics comprises the following components:

[0008] Saturated carboxyl polyester with a single bond structure.

[0009] According to an embodiment of the present invention, the polyester resin is implemented as a carboxyl polyester resin with an acid value of 25-45 mgKOH / g and a glass transition temperature Tg of 50-65°C.

[0010] According to one embodiment of the present invention, the curing agent is triglycidyl isocyanurate (TGIC) with an epoxy equivalent weight of 105 to 110 g / mol, or hydroxyalkylamide (HAA) with a hydroxyl equivalent weight of 80 to 90 g / eq.

[0011] According to one embodiment of the present invention, the leveling agent is PL200, PV67 or GLP588.

[0012] According to an embodiment of the present invention, the degassing agent is a mixture of benzoin and amide wax.

[0013] According to an embodiment of the present invention, the filler is a mixture of glass fiber powder and silicon dioxide powder.

[0014] According to an embodiment of the present invention, the median particle size D50 of the powder used to make polyester fiberglass is 25-50 μm, and the glass transition temperature Tg is 40-55°C.

[0015] According to another aspect of the present invention, in order to achieve at least one of the above advantages, the present invention provides a preparation method for making polyester glass fiber reinforced plastics, the method comprising:

[0016] S1001, preheating the finished glass fiber fabric to 90-110°C and then feeding it into the fluidized bed;

[0017] S1002, in a fluidized bed, after completely coating the glass fiber fabric with the powder for making polyester fiberglass, placing it into a mold and heating it to 150-180°C, baking it for 10-30 minutes until it is completely solidified, and then taking it out and cooling it.

[0018] According to one embodiment of the present invention, the preparation method for producing polyester glass fiber reinforced plastics includes:

[0019] Pre-apply release agent to the inside of the mold and let it dry.

[0020] According to one embodiment of the present invention, before step S1002, after the fluidized bed equipment is started, the air pressure is adjusted to ensure that the powder coating loaded therein flows evenly;

[0021] In step S1002, the preheated glass fiber fabric is fed into the fluidized bed and is completely coated with polyester powder with a thickness ranging from 300 to 1500 μm. DETAILED DESCRIPTION

[0022] The preferred embodiments described below are for illustrative purposes only, and those skilled in the art may readily conceive of other obvious variations. The basic principles of the present invention defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0023] A powder for making polyester fiberglass reinforced plastic according to a preferred embodiment of the present invention will be described in detail below. Specifically, the powder for making polyester fiberglass reinforced plastic includes the following components:

[0024]

[0025] Preferably, the polyester resin is implemented as a solid single-bond structured saturated carboxyl polyester.

[0026] Those skilled in the art will understand that the polyester fiberglass formed by applying the above-mentioned powder for making polyester fiberglass to the fiber fabric through a fluidized bed and heating and curing it has significantly improved aging resistance compared to the unsaturated polyester fiberglass produced by the traditional pultrusion process, and does not require an additional layer of coating, thereby effectively reducing the subsequent maintenance costs.

[0027] More preferably, the polyester resin in the present application is a carboxyl polyester resin having an acid value of 25 to 45 mgKOH / g and a glass transition temperature Tg of 50 to 65°C. The powder used in the present invention for making polyester fiberglass reinforced plastics has better heat resistance and will not cause thermal deformation even after being cured and baked at 120 to 130°C for 7 days, making it more suitable for use in some outdoor high-temperature exposure scenarios.

[0028] The higher the acid value of the polyester resin, the higher the crosslink density and hardness of the cured film, but the lower its flexibility. The glass transition temperature affects the storage stability of the powder coating. Therefore, the resin selected for this application has an acid value of 25-45 mgKOH / g and a glass transition temperature (Tg) of 50-65°C.

[0029] Preferably, the curing agent is triglycidyl isocyanurate (TGIC) with an epoxy equivalent weight of 105 to 110 g / mol, or hydroxyalkylamide (HAA) with a hydroxy equivalent weight of 80 to 90 g / eq.

[0030] Preferably, the leveling agent is PL200, PV67 or GLP588.

[0031] Preferably, the degassing agent is a mixture of benzoin and amide wax.

[0032] Preferably, the filler is a mixture of glass fiber powder and silicon dioxide powder.

[0033] Preferably, the median particle size D50 of the powder used to make polyester fiberglass is 25-50 μm, and the glass transition temperature Tg is 40-55°C.

[0034] According to another aspect of the present invention, the present invention also provides a preparation method for producing polyester glass fiber reinforced plastics, the method comprising:

[0035] Step S1001, preheating the finished glass fiber fabric to 90-110°C and then feeding it into a fluidized bed;

[0036] It is worth mentioning that in step S1001, if the temperature is too low, the powder coating will not be able to melt and adhere to the glass fiber fabric, and if the temperature is too high, the powder coating will solidify prematurely.

[0037] In step S1002, the powder for making polyester fiberglass reinforced plastic is completely coated on the glass fiber fabric in a fluidized bed. The powder is then placed in a mold and heated to 150-180°C. The mold is baked for 10-30 minutes to fully solidify the powder, and then removed and cooled. The temperature range can be increased to 130-200°C, and the baking time can be longer than 90 minutes, but this will slow down production.

[0038] Preferably, the preparation method for producing polyester glass fiber reinforced plastics comprises:

[0039] Step S1003: pre-apply a release agent on the inner side of the mold and wait for it to dry.

[0040] The release agent used in step S1003 is a silicone oil-based release agent.

[0041] Preferably, before step S1002, after the fluidized bed equipment is started, the air pressure is adjusted to ensure that the powder coating loaded therein flows evenly.

[0042] Preferably, in step S1002, after the preheated glass fiber fabric is fed into the fluidized bed, the polyester powder completely covers the glass fiber fabric to a thickness ranging from 300 to 1500 μm.

[0043] [Corrected 12 / 12 / 2024 according to Rule 91] Preferably, in step S1002, the curing temperature and time are determined by the polyester powder. After curing, the powder is removed and placed in air to cool naturally. The combination of different polyester resins and curing agents will affect the curing temperature and time, and there is no fixed relationship.

[0044] [Corrected 12 / 12 / 2024 in accordance with Article 91]

[0045] Example 1

[0046] The polyester resin is 50 parts of carboxyl polyester resin;

[0047] The curing agent is 4 parts of triglycidyl isocyanurate;

[0048] The leveling agent uses 1 part PL200;

[0049] The degassing agent is a mixture of 1 part benzoin and amide wax;

[0050] 40 parts of filler, wherein each component is in powder form, 25 parts of glass fiber powder and 15 parts of silicon dioxide powder.

[0051] Example 2

[0052] The polyester resin adopts 60 parts of carboxyl type polyester resin;

[0053] The curing agent is 5 parts of triglycidyl isocyanurate;

[0054] The leveling agent uses 1 part PV67;

[0055] The degassing agent is a mixture of 1 part benzoin and amide wax;

[0056] 30 parts of filler, wherein each component is in powder form, 20 parts of glass fiber powder and 10 parts of silicon dioxide powder.

[0057] Example 3

[0058] The polyester resin adopts 65 parts of carboxyl type polyester resin;

[0059] The curing agent uses 6 parts of hydroxyalkylamide;

[0060] The leveling agent uses 1 part PL200;

[0061] The degassing agent is a mixture of 2 parts of benzoin and amide wax;

[0062] The filler is 25 parts of each component in powder form, including 20 parts of glass fiber powder and 5 parts of silicon dioxide powder.

[0063] Example 4

[0064] The polyester resin adopts 70 parts of carboxyl polyester resin;

[0065] The curing agent uses 6 parts of triglycidyl isocyanurate;

[0066] The leveling agent uses 1 part of GLP588;

[0067] The degassing agent is a mixture of 2 parts of benzoin and amide wax;

[0068] The filler is 20 parts of glass fiber powder.

[0069] The main properties of the glass fiber reinforced plastic prepared by the present invention are compared with those of conventionally prepared glass fiber reinforced plastic as follows:

[0070] [Corrected 12 / 12 / 2024 in accordance with Rule 91] Those skilled in the art will understand that the embodiments of the present invention described above are intended only as examples and are not intended to limit the present invention. The advantages of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and illustrated in the embodiments. Any variations or modifications may be made to the embodiments of the present invention without departing from the principles described.

Claims

1. A powder for making polyester glass fiber reinforced plastics, characterized in that: The powder for making polyester glass fiber reinforced plastic comprises the following components: Polyester resin 50-80 parts 4-8 parts of curing agent 1-2 parts of leveling agent 1-2 parts of degassing agent The filler is 10 to 40 parts, wherein each component is in powder form, and the polyester resin is implemented as a saturated carboxyl polyester with a solid single bond structure.

2. The powder for making polyester glass fiber reinforced plastic according to claim 1, characterized in that: The polyester resin is implemented as a carboxyl polyester resin, with an acid value of 25 to 45 mgKOH / g and a glass transition temperature Tg of 50 to 65°C.

3. The powder for making polyester glass fiber reinforced plastic according to claim 1, characterized in that: The curing agent is triglycidyl isocyanurate (TGIC) with an epoxy equivalent of 105 to 110 g / mol, or hydroxyalkylamide (HAA) with a hydroxy equivalent of 80 to 90 g / eq.

4. The powder for making polyester glass fiber reinforced plastic according to claim 1, characterized in that: The leveling agent is PL200, PV67 or GLP588.

5. The powder for making polyester glass fiber reinforced plastic according to claim 1, characterized in that: The degassing agent is a mixture of benzoin and amide wax.

6. The powder for making polyester glass fiber reinforced plastic according to claim 1, characterized in that: The filler is a mixture of glass fiber powder and silicon dioxide powder.

7. The powder for making polyester glass fiber reinforced plastic according to claim 1, characterized in that: The median particle size D50 of the powder used for making polyester glass fiber reinforced plastic is 25-50 μm, and the glass transition temperature Tg is 40-55° C.

8. A method for preparing polyester glass fiber reinforced plastics, characterized in that: The method comprises: S1001, preheating the finished glass fiber fabric to 90-110°C and then feeding it into the fluidized bed; S1002, in a fluidized bed, after completely coating the powder for making polyester fiberglass on the glass fiber fabric, putting it into a mold and heating it to 150-180° C., baking it for 10-30 minutes to completely solidify it, and then taking it out and cooling it.

9. The method for making polyester glass fiber reinforced plastic according to claim 8, characterized in that: The preparation method for making polyester glass fiber reinforced plastics comprises: Pre-apply release agent to the inside of the mold and let it dry.

10. The method for making polyester glass fiber reinforced plastic according to claim 8, characterized in that: Before step S1002, after the fluidized bed equipment is started, the air pressure is adjusted to ensure that the powder coating loaded therein flows evenly; In step S1002, after the preheated glass fiber fabric is fed into the fluidized bed, the polyester powder completely coats it with a thickness ranging from 300 to 1500 μm.

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