阅读说明：本技术 一种手糊玻璃钢模具用的镁质胶凝材料 (Magnesium cementing material for hand-pasted glass fiber reinforced plastic mold ) 是由 沃成昌 沃研 于 2021-08-31 设计创作，主要内容包括：一种手糊玻璃钢模具用的镁质胶凝材料,质量组份包括：活性含量在60％以上的氧化镁粉100份,质量浓度为20-23％的氯化镁溶液100-120份或质量浓度为21-24％的硫酸镁溶液110-130份,外加剂2-3份,填料20-40份,植物纤维5-15份。其通过使用无机原料制得无机镁质胶凝材料,用该材料制成的无机玻璃钢模具绿色环保、成本低,生产和使用不会对环境有任何危害,可任意填埋填海,达到一定量的废弃物还可以机械粉碎后,加入水泥中做产品的填充料,做到原料产品的循环使用。用无机镁质胶凝材料制造的无机玻璃钢模具是有机玻璃钢模具成本的1/10-1/15,强度高,耐用性强,具有很强的实用性和广泛的适用性。(A magnesium cementing material for hand-pasted glass fiber reinforced plastic molds comprises the following components in parts by mass: 100 parts of magnesium oxide powder with the active content of more than 60 percent, 120 parts of magnesium chloride solution with the mass concentration of 20-23 percent or 130 parts of magnesium sulfate solution with the mass concentration of 21-24 percent, 2-3 parts of admixture, 20-40 parts of filler and 5-15 parts of plant fiber. The inorganic magnesium gel material is prepared by using inorganic raw materials, the inorganic glass fiber reinforced plastic mold prepared from the inorganic magnesium gel material is green and environment-friendly, has low cost, does not have any harm to the environment in production and use, can be randomly buried and filled in the sea, and can be added into cement to be used as a filler of a product after a certain amount of waste is mechanically crushed, so that the raw material product can be recycled. The inorganic glass fiber reinforced plastic mold made of the inorganic magnesium gel material is 1/10-1/15 of the cost of the organic glass fiber reinforced plastic mold, and has high strength, strong durability, strong practicability and wide applicability.)

1. The magnesium cementing material for the hand-pasted glass fiber reinforced plastic mold is characterized by comprising the following components in parts by mass:

100 parts of magnesium oxide powder, 120 parts of magnesium chloride solution or 130 parts of magnesium sulfate solution, 2-3 parts of an additive, 20-40 parts of a filler and 5-15 parts of plant fibers;

wherein the active content of the magnesium oxide powder is more than 60%, the mass concentration of the magnesium chloride solution is 20-23%, and the mass concentration of the magnesium sulfate solution is 21-24%.

2. The magnesium cement of claim 1, wherein the magnesium oxide powder comprises lightly calcined magnesium oxide from calcined magnesium carbonate ore.

3. The magnesium cement as claimed in claim 1, wherein the magnesium chloride comprises a byproduct obtained by extracting potassium from salt lake or a byproduct obtained by extracting sodium chloride from seawater.

4. The magnesium cement of claim 1, wherein the magnesium sulfate in the magnesium sulfate solution comprises industrial magnesium sulfate heptahydrate.

5. The magnesium cement of claim 1, wherein the admixture comprises at least 3 of inorganic acids, organic acids, sodium phosphate salts, and sulfates.

6. The magnesium cement of claim 1, wherein the filler comprises at least two of quartz powder, fly ash, silica fume, and metakaolin.

7. The magnesium cement material as claimed in claim 1, wherein the plant fiber is a processed product of waste crops, and comprises at least one of sawdust, straw powder, rice hull powder and rice bran powder, and the fineness of the plant fiber is 20-40 meshes.

8. The magnesium cement of claim 1, wherein the manual-paste glass-reinforced plastic mold is prepared by the following steps:

s1, spraying a release agent on the prototype;

s2, spraying the magnesium cementing material on the prototype, wherein the spraying thickness is 1-2mm, and the density is 1-2kg/m²；

S3, laying the first layer of glass fiber cloth on the magnesium cementing material, and compacting to enable the magnesium cementing material to penetrate out of meshes of the first layer of glass fiber cloth;

s4, spraying a magnesium cementing material on the first layer of glass fiber cloth, just covering the first layer of glass fiber cloth;

s5, laying a second layer of glass fiber cloth, and compacting to enable the magnesium cementing material to penetrate out of meshes of the second layer of glass fiber cloth;

s6, repeating the steps S4 and S5 until the molding thickness of the mold is reached, wherein the thickness is 3-10 mm;

s7, after the initial setting mould, covering a piece of moisture retention cloth, and maintaining at a heat preservation state to enable the magnesium cementing material to complete hydration reaction to generate a stable form and structure;

and S8, trimming and maintaining the well maintained mold, drying, and spraying a waterproof agent to obtain the hand-pasted glass steel mold.

9. The magnesium cement as claimed in claim 8, wherein the prototype material comprises any one of wood, metal, plastic, cement gypsum and sculpture mud.

10. The magnesium cement as claimed in claim 8, wherein the first layer of glass fiber cloth in step S3 has a mass of 50-70g/m²(ii) a The number of the second and subsequent layers in step S5The mass specification of the glass fiber cloth is 80-160g/m²；

The curing time in step S7 is 3-7 days, and the moisture content of the mold after drying in step S8 is less than 8%.

Technical Field

The invention relates to a magnesium cementing material, in particular to a magnesium cementing material for a hand-pasted glass fiber reinforced plastic mold.

Background

The manual pasting of the glass fiber reinforced plastic mold has been in China for over fifty years, and since the introduction of the unsaturated polyester resin production process in England from 253 factory in Changzhou in 1966 to produce unsaturated polyester resin, the unsaturated polyester resin is manually pasted into the glass fiber reinforced plastic mold, and then the glass fiber reinforced plastic mold is used for producing various glass fiber reinforced plastic products and cement GRC products.

The unsaturated polyester resin is prepared by diluting polyester generated by the reaction of high molecular organic acid and high molecular organic alcohol with styrene. The waste of glass fiber reinforced plastic products or moulds belongs to organic polymer waste, pollutes the environment when being buried (the natural degradation lasts for more than 200 years), and the recycling method comprises a chemical method, a physical method and a pyrolysis method, wherein in any method, the waste is worth investment and recovery when the waste amount is large, and the waste glass fiber reinforced plastic moulds are required to be used in a plurality of factories for producing GRC cement products and special-shaped decorative products for inner and outer walls of buildings, and are difficult to treat. Because the environment-friendly treatment of the organic glass reinforced plastic mold needs a certain amount of treatment to be worth investing in building the recovery device, any manufacturer in a plurality of manufacturers does not have the capacity to build the recovery device. The delivery to specialized treatment departments is also costly.

If an inorganic cementing material is used for manufacturing an inorganic glass fiber reinforced plastic mold, the organic glass fiber reinforced plastic mold manufactured by unsaturated polyester resin of the organic cementing material is replaced, and the treatment of the waste mold becomes simple for enterprises. The raw material is used as the filler after being buried or crushed, thereby not only not polluting the environment, but also saving the treatment cost and greatly reducing the mold cost.

Disclosure of Invention

In order to achieve the above purpose, the present invention aims to provide a method for manufacturing a magnesium-based cementing material for hand-pasted glass fiber reinforced plastic molds and a step of hand-pasted inorganic glass fiber reinforced plastic molds.

In order to achieve the above object, the present invention adopts the following technical solutions:

the magnesium cementing material for the hand lay-up glass fiber reinforced plastic mold comprises the following components in parts by mass:

100 parts of magnesium oxide powder, 120 parts of magnesium chloride solution or 130 parts of magnesium sulfate solution, 2-3 parts of an additive, 20-40 parts of a filler and 5-15 parts of plant fibers;

wherein the active content of the magnesium oxide powder is more than 60%, the mass concentration of the magnesium chloride solution is 20-23%, and the mass concentration of the magnesium sulfate solution is 21-24%.

The magnesium oxide powder comprises light-burned magnesium oxide obtained by calcining magnesium carbonate ore.

The magnesium chloride comprises a byproduct obtained after potassium is extracted from a salt lake or a byproduct obtained after sodium chloride is extracted from seawater.

The magnesium sulfate in the magnesium sulfate solution comprises industrial magnesium sulfate heptahydrate.

The additive comprises at least 3 of inorganic acid, organic acid, sodium phosphate and sulfate.

The filler comprises at least two of quartz powder, fly ash and silica fume metakaolin.

The plant fiber is processed product of waste crops, and comprises at least one of sawdust, straw powder, rice hull powder and rice bran powder, and the fineness of the plant fiber is 20-40 meshes.

All the components are mixed and stirred into slurry to form the magnesium cementing material.

The hand lay-up glass reinforced plastic mould comprises the following steps:

s1, placing the model on a plane workbench, spraying a release agent on the model, and spraying more than 50mm wide on the edge of the model;

s2, spraying the magnesium cementing material on the model, wherein the spraying thickness is 1-2 mm;

s3, laying the first layer of glass fiber cloth on the magnesium cementing material, and compacting and brushing the first layer of glass fiber cloth flat by using a brush to enable the magnesium cementing material to penetrate out of meshes of the first layer of glass fiber cloth;

s4, spraying a magnesium cementing material on the first layer of glass fiber cloth, just covering the first layer of glass fiber cloth;

s5, laying a second layer of glass fiber cloth, and compacting to enable the magnesium cementing material to penetrate out of meshes of the second layer of glass fiber cloth;

s6, repeating the steps S4 and S5 to reach the forming thickness of the mold, wherein the thickness of the mold is 3-10mm generally and the number of layers of glass fiber cloth is 4-10 according to different sizes of the model area;

s7, curing the solidified mould to make the magnesium cementing material complete hydration reaction and generate a stable form and structure;

s8, taking out the model after maintenance, cutting edges of the model and drying the model;

and S9, spraying the protective paint on the die for one or two times.

The first layer of glass fiber cloth in the step S3 has the mass specification of 50-70g/m²(ii) a The quality specifications of the second layer and the following layers of glass fiber cloth in the step S5 are all 80-160g/m²(ii) a Maintaining for at least 3 days in step S7, and drying in step S8 to obtain water content of the mold<8% is preferred.

The invention has the advantages that:

the magnesium cementing material for the hand lay-up glass fiber reinforced plastic mold disclosed by the invention uses inorganic substances as components, so that unsaturated polyester resin is effectively replaced, and the inorganic magnesium cementing material is prepared by using inorganic raw materials. The manufacturing process of the inorganic glass fiber reinforced plastic (GRMC) manufactured by using the inorganic magnesium cementing material is nontoxic and tasteless, a phase structure with stable shape and stable structure is generated through hydration reaction of inorganic raw materials completed in the maintenance stage of moisture preservation and heat preservation, plain glass fiber cloth with certain meshes is used for replacing dense mesh glass fiber cloth for organic glass fiber reinforced plastic to be used as a reinforcing layer, and then plant fibers are combined, so that the Mohs hardness of the manufactured inorganic glass fiber reinforced plastic mold can reach 5-7; compared with a mould which is made of unsaturated polyester resin as a main component, the hardness is effectively improved, the use times of the mould are prolonged, and the service life of the mould is prolonged.

The mould made of inorganic magnesium cementing material can be freely buried and filled in the sea after being abandoned in the later period of use, the components of the mould are the components of natural soil and minerals, mainly the components of inorganic salts of magnesium, calcium, silicon and aluminum, and the mould can not cause any pollution and damage to the environment. The waste reaching a certain amount can be mechanically crushed and then added into cement to be used as a filling material of the product, so that the raw material product can be recycled.

The magnesium cementing material and the inorganic glass fiber reinforced plastic mold made of the material have the characteristics of environmental protection and low cost, and have no harm to the environment in production and use, and the inorganic glass fiber reinforced plastic mold made of the inorganic magnesium cementing material is 1/10-1/15 of the cost of an organic glass Fiber Reinforced Plastic (FRP), has high strength and strong durability, and has strong practicability and wide applicability.

Drawings

FIG. 1 is a mold used to prepare hand lay-up GRP molds (FIG. a is a front view, FIG. b is a side view).

FIG. 2 is a drawing of a hand-lay-up GRP mold made with the magnesium cement of example 1 (front view in fig. c and back view in fig. d).

Fig. 3 is a diagram of a GRC product-roofing tile made with the hand-lay-up glass-reinforced plastic mold of fig. 2 (panel e is the front and panel f is the side).

Detailed Description

The invention is described in detail below with reference to the figures and the embodiments.

A magnesium cementing material for a hand-pasted glass fiber reinforced plastic mold comprises the following components in parts by mass:

100 parts of magnesium oxide powder, 120 parts of magnesium chloride solution or 130 parts of magnesium sulfate solution, 2-3 parts of admixture, 20-40 parts of filler and 5-15 parts of plant fiber.

Wherein, the magnesium oxide powder can be light-burned magnesium oxide calcined by magnesium carbonate ore, and the active content is more than 60 percent.

The magnesium chloride solution can be a byproduct obtained by extracting potassium from salt lake or a byproduct obtained by extracting sodium chloride from seawater, and has a mass concentration of 20-23%.

The magnesium sulfate solution has a mass concentration of 21-24%, and the magnesium sulfate can be industrial magnesium sulfate heptahydrate.

The additive can be at least 3 of inorganic acid, organic acid, sodium phosphate and sulfate; inorganic acids include phosphoric acid, organic acids include citric acid; the sodium phosphate salt includes trisodium phosphate, sodium tripolyphosphate and sodium dihydrogen phosphate, and the sulfate salt includes ferrous sulfate, aluminum sulfate and calcium sulfate.

The filler can be at least two of quartz powder, fly ash, silica fume and metakaolin.

The plant fiber can be processed product of waste crops, including at least one of saw dust, straw powder, rice hull powder, and bran powder, and has fineness of 20-40 mesh.

The magnesium cementing material for preparing the hand-pasted glass fiber reinforced plastic mold comprises the following steps:

first, there is a prototype (also called model), which can be made of various materials and in various ways, such as wood, metal, plastic plate, plaster cement, sculpture material. As shown in FIG. 1, the roof tile model is adhered by plastic plates (a is a front view, and b is a side view).

After the mold is available, the process steps for hand pasting the inorganic GRP mold are the same as for hand pasting the GRP mold except that the unsaturated polyester resin is replaced with a magnesium cement.

The method comprises the following specific steps:

s1, spraying or manually coating a release agent on the prepared model;

s2, spraying or coating a magnesium cementing material on a prototype of the existing release agent, wherein the spraying thickness is 1-2 mm;

s3, cutting the steel plate into pieces with the mass of 50-70g/m²The first layer of glass fiber cloth is laid on the sprayed magnesium cementing material according to the shape of a model and compacted, so that the magnesium cementing material is penetrated out of meshes of the first layer of glass fiber cloth; the second layer of glass fiber cloth is tightly attached to the first layer of glass fiber cloth;

s4, spraying a magnesium cementing material on the first layer of glass fiber cloth, just covering the first layer of glass fiber cloth;

s5, paving the concrete again with the quality specification of 80-160g/m²Compacting the second layer of glass fiber cloth to ensure that the magnesium cementing material is penetrated out of meshes of the second layer of glass fiber cloth;

s6, repeating the steps S4 and S5 according to the size and thickness of the mould to reach the forming thickness of the mould, wherein the thickness is 3-10mm generally;

s7, covering a moisture-preserving cloth on the prepared mould after initial setting, and preserving heat and maintaining for at least 3 days to enable the magnesium cementing material to complete hydration reaction to generate a mould with stable shape and structure, wherein the glass fiber reinforced plastic mould has certain hardness, certain toughness and elasticity and is convenient to produce;

s8, trimming and maintaining the well maintained die, naturally drying to enable the water content to be less than 8%, and spraying protective paint.

The protective coating can be any one of epoxy resin, acrylic acid, polyurethane and automatic spray paint according to the use requirement.

Preparation of magnesium cement example:

example 1

10kg of magnesium oxide, 10-11kg of magnesium chloride solution (the mass concentration is 20-23%), 0.2kg of additive (0.1 kg of phosphoric acid, 0.05kg of ferrous sulfate and 0.05kg of aluminum sulfate respectively), 2-3kg of quartz powder, 0.5-1kg of fly ash and 0.5kg of sawdust, wherein the additive is dissolved in the magnesium chloride solution, and other components are added, mixed and stirred into uniform slurry for later use.

Example 2

10kg of magnesium oxide, 9-11kg of magnesium chloride solution (mass concentration is 20-23%), 0.2kg of additive (0.1 kg of phosphoric acid: 0.05kg of trisodium phosphate and 0.05kg of aluminum sulfate), 1kg of silica fume, 1kg of quartz powder and 1-1.5kg of sawdust, wherein the additive is dissolved in the magnesium chloride solution, and other components are added and mixed to form uniform slurry for later use.

Example 3

10kg of magnesium oxide, 10-12kg of magnesium sulfate solution (mass concentration is 20-24%), 0.2kg of additive (0.1 kg of citric acid, 0.02kg of phosphoric acid and 0.08kg of aluminum sulfate), 0.5-1kg of silica fume, 2-3kg of fly ash and 0.5-1kg of sawdust, wherein after the additive is added into the magnesium sulfate solution to be dissolved, other components are added under the condition of stirring, and the mixture is uniformly stirred to be in a slurry state.

The magnesium cement prepared above can be used for hand-pasting of the glass fiber reinforced plastic mold, and the method and steps of hand-pasting of the glass fiber reinforced plastic mold are completely the same no matter whether the cement is used in any of the three cases, for example, as follows:

a conventional model of a small roof tile is made of a 6mm thick PVC plastic sheet cut and bonded as shown in fig. 1, and the model has a length × width × thickness of 100cm × 100cm × 0.6cm and a corrugation height of 3cm, as shown in the front and side of fig. a and b.

And S1, placing the model on a plane workbench, and spraying a release agent, wherein the release agent covers the whole model and exceeds the peripheral edge of the model by 5 cm.

And S2, spraying or manually brushing the magnesium cementing material on all the positions of the model where the release agent is sprayed, wherein the thickness is 1-2 mm.

S3, uniformly spreading cut plain cloth with the mass of 50-70g per square meter on the sprayed gelling material according to the shape of the model, compacting and brushing the glass fiber cloth according to the shape of the model by using a brush to ensure that the gelling material is penetrated out of meshes of the glass fiber cloth, and uniformly brushing the penetrated gelling material.

And S4, spraying a layer of gel material to a thickness (about 1-2mm) just enough to cover the first layer of glass fiber cloth.

And S5, laying a second layer of glass fiber cloth, wherein the operation method is the same as S3, the second layer of glass fiber cloth uses the glass fiber cloth with the weight of 80-160g per square meter, the glass fiber cloth is still laid on the sprayed gelling material according to the shape of the model, and the glass fiber cloth is still compacted and brushed flat by a brush, so that the glass fiber cloth is tightly attached to the upper layer of glass fiber cloth under the condition of being filled with the slurry.

And S6, repeating the operations of S4 and S5 to reach the thickness of the mould. According to the difference of the model area, the area of the die is also different, the thickness of the die is related to the area, the thick points with large area are generally used, the number of layers of the cloth is also large, and vice versa. Typically the thickness of the mould is between 3 and 10 mm.

And S7, standing and maintaining after the required thickness is achieved, hardening and curing the cementing material and the glass fiber cloth into a whole, and demolding after 24 hours, namely separating the mold from the manually pasted mold.

S8, continuing to maintain the mold separated from the model in a moisture-preserving environment at 20-30 ℃ for at least 3 days (namely, maintaining moisture after covering plastic cloth), then cutting the edge of the mold neatly, naturally drying to reduce the water content of the mold to below 8%, and coating protective paint for 1-2 times, wherein the lower the water content is, the better the adhesive force between the protective paint and the mold is.

S9, the protective coating sprayed on the mould is any one of polyurethane, epoxy resin and nitrolacquer, and the purpose of spraying the protective coating is to facilitate demoulding when the mould is used for producing products.

The obtained mold was 5mm thick and had an open area of 1.3m2 as shown in FIG. 2. Fig. c is the front side of the mold and fig. d is the back side of the mold. The protective coating of the mold in fig. c is a black lacquer.

As shown in fig. 3, is a finished view of a roof tile made using the resulting mold as shown in fig. 2 (fig. e is a front view, and fig. f is a side view).

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It should be understood by those skilled in the art that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by using equivalent alternatives or equivalent variations fall within the scope of the present invention.