TWI840089B - Foaming composition and foam material using marine waste - Google Patents

Abstract

The present invention provides a foaming composition, which uses marine waste as a filler, and uses a completely-recycled polymer material as a substrate, including: 49 to 70 wt% of a completely-recycled polymer material; 29 to 50 wt% of shell powder; 0.01 to 3 wt% a coupling agent; 0.5 to 10 wt% of a blowing agent; 0.25 to 3 wt% of a bridging agent; and 0.2 to 15 wt% of a processing auxiliary agent. In addition, the present invention also provides a foam material formed by said foaming composition through foaming process. Wherein, the end portion of the inorganic molecular are modified or grafted by using the coupling agent to improve the bonding between the organic polymer and the inorganic material, thereby improving the compatibility between the shell powder (inorganic filler) and the polymer material(organic substrate) in the foam material.

Description

Foaming compositions and foaming materials using marine waste

The present invention relates to a foaming composition and a foaming material, in particular to a foaming composition and a foaming material using marine waste as a filler and using a fully recycled polymer material as a base material.

In the plastic manufacturing industry, adding inorganic substances as fillers to reduce raw material costs is a common method in the industry. However, the poor compatibility between organic polymer substrates and inorganic fillers has always been a problem that the plastic industry has to face. Poor compatibility will cause precipitation and even lead to a decline in mechanical properties, which directly affects the appearance of the product.

For traditional EVA (Ethylene Vinyl Acetate) and chemically foamed PE (Poly Ethylene) physical foaming materials, generally speaking, in the industry, the maximum addition ratio of calcium carbonate (such as shell powder) filler in the foaming material is about 15 wt%. This addition amount is already the limit. The foaming molding of the finished product is quite difficult, and the problems of severe surface whitening and agglomeration cannot be effectively overcome, resulting in unstable foaming, insufficient foaming structure strength, low foaming ratio, and too hard hardness. As a result, it is impossible to cut and process it because of severe embrittlement or cracking. Therefore, in foaming materials, there is little research and development on the technology of using calcium carbonate filler and PE or EVA substrate to mix and form foaming materials.

In addition, in the prior art, even if calcium carbonate (especially shell powder) is used to mix with polymer materials to form foam materials, there are still the following problems: first, the physical properties of the polymer material seriously decline after mixing with the shell powder; the shell powder and the polymer material are not mixed evenly, which easily causes calcium carbonate agglomeration; third, the poor compatibility between the shell powder and the polymer material will cause precipitation, which directly affects the appearance of the product.

In view of the above-mentioned shortcomings, the purpose of the present invention is to improve the compatibility of shell powder (inorganic filler) and polymer material (organic substrate) in the foaming material. In addition to using processing aids such as lubricants to help disperse the inorganic matter, the ends of the inorganic molecules are modified or grafted through coupling agents to improve the bonding between the organic polymer and the inorganic material.

In order to achieve the aforementioned purpose, the present invention provides a foaming composition, which uses marine waste as a filler and uses a fully recycled polymer material as a substrate, including: fully recycled polymer material, shell powder, coupling agent, foaming agent, bridging agent and processing aid, wherein, based on the total amount of the foaming composition as 100 wt%, the content of the fully recycled polymer material is 49 to 70 wt%, the content of the shell powder is 29 to 50 wt%, the content of the coupling agent is 0.01 to 3 wt%, the content of the foaming agent is 0.5 to 10 wt%, the content of the bridging agent is 0.25 to 3 wt%, and the content of the processing aid is 0.2 to 15 wt%.

According to one embodiment, the fully recycled polymer material comprises fully recycled PE.

According to one embodiment, the shell powder comprises shellfish powder, oyster shell powder, mussel shell powder, abalone shell powder, clam shell powder, nine-hole shell powder, rattan pot shell powder, or snail shell powder.

According to one embodiment, the coupling agent comprises a titanium ester.

According to one embodiment, the blowing agent comprises azodicarbonamide.

According to one embodiment, the bridging agent comprises BIBP.

According to one embodiment, based on 100 wt% of the total amount of the foaming composition, the processing aid comprises: 0.1 to 5 wt% of zinc stearate; 0.1 to 5 wt% of zinc oxide; and 0.03 to 3 wt% of stearic acid.

According to one embodiment, the foaming composition further includes at least one of a flame retardant, an antistatic agent, a pigment, and a softener.

In addition, in order to achieve the aforementioned purpose, the present invention also provides a foaming material using marine waste, which is formed by foaming the above-mentioned foaming composition.

According to one embodiment, when the drop height is 60 to 80 cm, the G value of the drop test of the foam material is between 45 and 110 N/kg.

In summary, the present invention improves the compatibility of inorganic fillers and organic substrates by using a coupling agent in the foaming composition. Currently, in the foaming material using shell powder and fully recycled polymer materials, the shell powder addition amount can reach up to 50 wt%, the surface whitening and agglomeration phenomena are greatly improved, the foaming stability, foaming structure strength, foaming ratio, cutting and processing feasibility are greatly improved, and stable production is possible. More importantly, based on the responsibility of protecting the ecological environment, the present invention treats marine waste (especially shells) and blends them with fully recycled polymer materials to make foaming materials, so as to achieve the recycling of waste and reduce the use of polymers (such as plastics, rubbers, etc.).

The content of the present invention will be described in detail below.

In the following, when the description of the well-known technical means in the art is determined to be likely to obscure the subject matter in certain embodiments of the present invention, such description will be omitted. The terms used herein such as "include", "comprise", "have", "compose", and "composed of" are generally intended to allow for the presence of other elements/components unless these terms are used together with the term "only". As used herein, unless otherwise specified, the singular form is intended to include the plural form.

When time relative terms, such as "after", "subsequently", "next", "before", etc., are used to describe the process or steps of the method, these terms can be used to describe the discontinuous process or steps, unless these terms are used with the terms "directly" or "immediately". In addition, the term "may" fully includes all the meanings of the term "can".

In the absence of any contradiction, the technical features of any embodiment of the foaming composition and foaming material described in this specification can be applied to other embodiments of the foaming composition and foaming material of the present invention.

In order to achieve the recycling of waste and reduce the use of polymers such as plastics, rubbers, etc., the present invention provides a foaming composition, which uses marine waste such as shell powder as a filler and uses a fully recycled polymer material as a base material.

However, adding calcium carbonate (such as marine waste such as shell powder) as a filler in foam products will cause the mechanical properties of the foam material, such as IZOD (impact resistance), MI (melt index), tensile strength, etc. to decline seriously. This is because calcium carbonate is an inorganic substance and cannot form a good bond with the polymer material after mixing, which can easily cause the inorganic filler to be unevenly dispersed in the organic polymer, resulting in interface defects between the two materials.

Therefore, the present invention changes the formula of the foaming composition and uses a coupling agent to modify the surface of the shell powder. The physical properties of the shell powder and the polymer material after mixing and foaming are better than those of the original polymer material. Some mechanical properties such as shock absorption effect and surface hardness are higher than those of the original plastic material, and the tensile strength and elongation are significantly improved.

The foaming composition of the present invention comprises: 49 to 70 wt% of fully recycled polymer material; 29 to 50 wt% of shell powder; 0.01 to 3 wt% of coupling agent; 0.5 to 10 wt% of foaming agent; 0.25 to 3 wt% of bridging agent; and 0.2 to 15 wt% of processing aid.

According to one embodiment, based on the total amount of the foaming composition as 100 wt%, the content of the fully recycled polymer material can be 49 wt% or more, or 50 wt% or more, or 55 wt% or more, and 70 wt% or less, or 65 wt% or less.

Fully recycled polymer materials may include fully recycled plastics, rubbers, etc. The above-mentioned plastics may include: non-biomass plastics, such as PE; or biomass synthetic plastics, such as polylactic acid (PLA) or starch-based polymers, etc. The above-mentioned rubber may include: natural rubber, such as isoprene rubber; or synthetic rubber, such as biomass synthetic rubber. The biomass synthetic plastic may be a biodegradable biomass synthetic plastic.

The above-mentioned bio-based synthetic rubber may include: bio-based ethylene propylene diene monomer (EPDM), such as di-ethylene propylene rubber or ter-ethylene propylene rubber; bio-based polyamide (PA); or bio-based polyethylene-2,5-furandicarboxylate (PEF), etc.

The biomass-based synthetic plastic or biomass-based synthetic rubber is a polymer material made from natural renewable biomass, such as biomass from oak, corn or sugar cane.

However, the fully recycled polymer material is not limited thereto, and may be any polymer material known in the art that can be used for foaming.

According to one embodiment, based on 100 wt% of the total amount of the foaming composition, the content of the shell powder can be 29 wt% or more, or 30 wt% or more, or 35 wt% or more, and 50 wt% or less, or 45 wt% or less.

The shell powder includes shellfish powder, oyster shell powder, mussel shell powder, abalone shell powder, clam shell powder, nine-hole shell powder, rattan pot shell powder, or snail shell powder.

Preferably, based on the total amount of shell powder as 100wt%, the content of shell powder particles in the shell powder that can pass through a 250-mesh screen is above 50wt%.

According to one embodiment, based on the total amount of the foaming composition as 100wt%, the content of the coupling agent can be 0.01wt% or more, 0.05wt% or more, or 0.1wt% or more, or 0.5wt% or more, or 1wt% or more, or 1.25wt% or more, or 1.5wt% or more, and 3wt% or less, or 2.75wt% or less, or 2.5wt% or less.

The coupling agent includes titanium ester, wherein the titanium ester can be in the form of liquid oil and/or solid powder.

In order to make the foam material have an appropriate foaming density, the foaming composition of the present invention preferably contains 3 to 10 wt% of foaming agent.

According to one embodiment, based on the total amount of the foaming composition as 100wt%, the content of the foaming agent can be 0.5wt% or more, 1wt% or more, 2wt% or more, 3wt% or more, or 4wt% or more, or 5wt% or more, or 6wt% or more, and is 10wt% or less, or 9wt% or less, or 8wt% or less, or 7wt% or less.

The foaming agent may include a physical foaming agent and/or a chemical foaming agent. A physical foaming agent may be a low-boiling or volatile liquid, or a gas that is pressurized into a liquid, such as a low-grade aliphatic hydrocarbon, an aromatic hydrocarbon, a halogenated hydrocarbon, or liquid carbon dioxide. A chemical foaming agent may be a substance that reacts to produce gas, such as azodicarbonamide (ADC), N,N’-dinitrosopentamethylenetetramine (DPT), or 4,4’-disulfonylhydrazine diphenyl ether (OBSH).

According to one embodiment, based on the total amount of the foaming composition as 100wt%, the content of the bridging agent can be 0.25wt% or more, 0.5wt% or more, 1wt% or more, or 1.25wt% or more, or 1.5wt% or more, and 3wt% or less, or 2.75wt% or less, or 2.5wt% or less.

The bridging agent may include, for example, a sulfur bridging agent, a lignin bridging agent and/or a modified lignin bridging agent. The bridging agent may include, for example, BIBP (C ₆ H ₄ [C(CH ₃ ) ₂ OOC(CH ₃ ) ₃ ] ₂ ).

The processing aid may include, for example, a lubricant. For example, based on 100 wt% of the total amount of the foaming composition, the processing aid may include: 0.1 to 5 wt% of zinc stearate; 0.1 to 5 wt% of zinc oxide; and 0.03 to 3 wt% of stearic acid.

According to one embodiment, based on the total amount of the foaming composition as 100wt%, the content of zinc stearate as a processing aid can be 0.1wt% or more, 0.5wt% or more, 1wt% or more, 1.5wt% or more, or 2wt% or more, or 2.5wt% or more, and is 5wt% or less, or 4.5wt% or less, or 4wt% or less, or 3.5wt% or less.

According to one embodiment, based on the total amount of the foaming composition as 100 wt%, the content of zinc oxide as a processing aid can be 0.1 wt% or more, 0.5 wt% or more, 1 wt% or more, 1.5 wt% or more, or 2 wt% or more, or 2.5 wt% or more, and is 5 wt% or less, or 4.5 wt% or less, or 4 wt% or less, or 3.5 wt% or less.

According to one embodiment, based on the total amount of the foaming composition as 100 wt%, the content of stearic acid as a processing aid can be 0.03 wt% or more, 0.05 wt% or more, 0.1 wt% or more, 0.3 wt% or more, or 0.5 wt% or more, or 1 wt% or more, and is 3 wt% or less, or 2.5 wt% or less, or 2 wt% or less.

The foaming composition of the present invention may further include at least one of a flame retardant, an antistatic agent, a pigment and a softener.

The flame retardant may be a phosphorus-containing flame retardant, a silicon-containing flame retardant, or other flame retardants.

The antistatic agent may be a cationic antistatic agent, an anionic antistatic agent, an amphoteric antistatic agent, or a non-ionic antistatic agent.

The pigment may be, for example, petroleum-based carbon black or a pigment derived from biomass or any other known pigment. Petroleum-based carbon black is, for example, a substance formed by carbonization of petroleum. Biomass-based pigments include, but are not limited to, plant-based carbon black, such as bamboo charcoal, wood charcoal, or rice husk carbon black.

Preferably, based on 100 wt % of the total amount of the pigment, the content of the pigment particles that can pass through a 250-mesh screen in the pigment is above 50 wt %.

In addition, in order to achieve the aforementioned purpose, the present invention also provides a foam material, which is formed by foaming the above-mentioned foaming composition.

When the drop height is 60 to 80 cm, the G value of the drop test of the foam material of the present invention is between 45 and 110 N/kg.

Specifically, referring to the manufacturing process of FIG. 1 , according to an embodiment of the present invention, the various components in the foaming composition of the present invention can be directly added together for mixing and foaming to manufacture the foaming material of the present invention.

Specifically, in the pre-treatment step S11, the shells are subjected to static sun exposure, impurity removal, cleaning and drying, crushing, calcining and screening to obtain clean shell powder with uniform particle size; in the mixing step S12, the above-mentioned clean shell powder is directly added together with other components in the foaming composition for mixing; in the foaming step S13, the above-mentioned mixture is foamed into a sheet foam material; and, in the cutting step S14, the above-mentioned sheet foam material is cut into a required size.

Alternatively, referring to the manufacturing process of FIG. 2 , according to another embodiment of the present invention, the shell powder may be first modified using a coupling agent, and then the modified shell powder is added together with other components in the foaming composition for mixing and foaming to produce the foaming material of the present invention.

Specifically, the pretreatment step S21 can be carried out in the same manner as the pretreatment step S11; in the modification step S22, the clean shell powder is modified using a coupling agent; in the mixing step S23, the modified shell powder is added together with other ingredients in the foaming composition for mixing; and, the foaming step S24 and the cutting step S25 can be carried out in the same manner as the foaming step S13 and the cutting step S14, respectively.

Alternatively, the foamed material of the present invention can be prepared by adding the ingredients in the following order for mixing and foaming: fully recycled polymer material → modified shell powder → processing aid → foaming agent → bridging agent.

In the present invention, natural shell powder is mechanically ground into calcium carbonate (CaCO ₃ ) powder, and then the calcium carbonate powder is subjected to chemical surface treatment (coupling modification) to obtain activated calcium carbonate powder, which is packaged as a finished product after fineness grading, namely the above-mentioned modified shell powder. The activated calcium carbonate powder obtained by chemical surface treatment has better dispersibility, reinforcement and electrical insulation than general heavy calcium carbonate powder. For rubber or plastic products, the above-mentioned activated calcium carbonate powder can make the product have better tear resistance and flexure resistance. For industrial products, the above-mentioned activated calcium carbonate powder can maintain good fluidity or extrudability during the processing process, and can make the product have better tear resistance and flexure resistance.

Specifically, the process of modifying shell powder to prepare modified shell powder includes: weighing a titanium ester coupling agent and ethanol (ETOH) and mixing them evenly, dispersing and dissolving the titanium ester coupling agent in the ethanol; taking another shell powder and placing it in a mixer (HENSCHEL high speed mixer) and heating it to 60 to 80°C for low-speed stirring and mixing, and then spraying the titanium ester coupling agent solution onto the shell powder. After treating for 10 to 40 minutes, the powder is taken out and placed in an oven and heated at 80 to 100°C for 1 to 2 hours to prepare the modified shell powder .

Referring to the manufacturing process of FIG. 3 , in the embodiment of the present invention, first, in the pre-treatment step S31, the oyster shell is exposed to the sun to remove impurities, then cleaned and dried using 38°C hot water in a high pressure 360-degree rotation manner, then pulverized using a coarse crusher and screened, then calcined at a high temperature of 1300°C and cooled, and finally pulverized using a fine crusher and screened using a nano screen to obtain oyster shell powder with an average particle size of 1300 nm.

Next, in the reforming and mixing step S32, 6 kg of PE granules and 4 kg of nano-grade oyster shell powder are placed in an oven at 80°C for 4 hours, and then respectively fed into a granule tank and a powder tank, and vacuum filtration is used to remove fine dust, and then the PE granules and oyster shell powder are sucked into a measuring bucket for weighing and 0.2 kg of coupling agent (titanium ester) is added, and then stirred and mixed at 50 to 90°C in a high-speed mixer, and then stirred at a temperature below 50°C in a cooler for 5 to 20 minutes for cooling.

Thereafter, in the mixing and granulating step S33, a processing aid (0.3 kg of zinc stearate + 0.3 kg of zinc oxide + 0.15 kg of stearic acid) is added to a kneader for mixing, and then granulated using a twin-screw granulator, and cooled to room temperature in a cooling barrel, and finally screened using a vibrating machine to obtain PE/oyster shell powder mixed granules.

In the manufacturing process of PE/oyster shell powder mixed granules, the mixing degree can be increased by continuing to stir in the cooler, and the purpose of cooling is to prevent the volatility of the processing aids added later. In addition, during the mixing process of the kneader, the mixing can be carried out at a temperature of 140 to 160°C due to natural heating due to friction. In addition, the purpose of using a vibrator for screening is to vibrate the granules into shape and avoid sticking to each other, while removing granules with too large particle size.

Then, in the mixing step S34, the PE/oyster shell powder mixed granules, the foaming agent (azodicarbonamide) and the bridging agent (BIBP) selected by the vibrating machine are put into the mixing tank at a weight ratio of 110:6.5:2 for mixing, and then kneaded and leveled by a double roller at 100 to 120° C., and then leveled into sheets by a three-roll grinder at 80 to 100° C., and then leveled and pulled by a roller conveyor, and then cut into sheets.

Finally, in the foaming step S35, the foaming is performed at 130 to 160 degrees C in a molding press, and then left to stand at room temperature for 30 to 60 minutes for curing to produce a PE/oyster shell powder foam material (sheet).

In the manufacturing process of foam materials, the purpose of using a three-roll grinder for leveling is to avoid warping or unevenness on the surface of the sheet.

According to the product requirements, a cutting step S36 can be further performed to cut the aforementioned PE/oyster shell powder foam material into appropriate sizes. Hardness, tensile strength, tear strength and elongation

The PE/oyster shell powder foam material (Example) and the conventional expanded polyethylene (EPE) (Comparative Example) were tested for hardness using a SHORE C-type durometer according to ASTM D2240, tested for tensile strength according to ASTM D638, tested for tear strength according to ASTM D624, and tested for elongation according to ASTM D638. The results are shown in Table 1.

Table 1. Physical properties of foaming materials Test samples Hardness Tensile Strength (kg/cm) Tear Strength (kg/cm) Elongation (%) Embodiment 40-42 8.12 3.78 125% Comparison Example 36-38 2.8 3.04 15% Impact strength

According to the CNS2999 standard method, the PE/oyster shell powder foam material (Example) and the conventional expanded polyethylene (EPE) (Comparative Example) were subjected to a drop test. The results are shown in Tables 2 and 3.

Table 2. Drop experiment with a drop height of 61 cm Thickness (mm) * Length (mm) 30*30 30*40 30*50 30*60 Area = length * width (cm ² ) 10.5 14 17.5 twenty one Example G value (N/kg) 66.31 54.34 49.66 49.50 Comparative example G value (N/kg) 77.94 73.36 64.85 64.02

Table 3. Drop experiment with a drop height of 76 cm Thickness (mm) * Length (mm) 30*30 30*40 30*50 30*60 Area = length * width (cm ² ) 10.5 14 17.5 twenty one Example G value (N/kg) 101.82 94.56 69.70 71.59 Comparative example G value (N/kg) 118.11 106.04 88.81 87.82

In Table 2 and Table 3, thickness, length, width and area refer to the thickness, length, width and area of the foamed sheets, wherein the width of each sheet is 3.5 cm.

From the experimental results in Tables 1 to 3, it can be seen that the foamed composition made by foaming and mixing shell powder and fully recycled polymer materials of the present invention can improve physical properties to be better than traditional foamed polyethylene through formula changes and shell powder surface modification technology. Some mechanical properties such as shock absorption effect (such as the G value in the above table, where the lower the G value, the higher the impact resistance and the better the shock absorption effect) and surface hardness are higher than traditional foamed polyethylene. In particular, the tensile strength and elongation of the foam material of the present invention are respectively increased to about 3 times and about 8 times that of traditional foamed polyethylene, and the physical properties are significantly improved.

Generally speaking, in the industry, most applications of adding calcium carbonate to polymer materials do not have surface appearance or physical property requirements, such as toys, simple daily necessities, and various packaging buffer materials. However, the foaming material of the present invention not only improves the mechanical properties but also improves the surface appearance, thereby expanding the range of applicable product categories. In addition, flame retardants or antistatic agents can be added to the foaming composition of the present invention to produce related effects, so that it can be used as a packaging material for the outer shell and internal precision components of 3C electronic products.

In summary, the present invention improves the compatibility of inorganic fillers and organic substrates by using a coupling agent in the foaming composition. Currently, in the foaming material using shell powder and fully recycled polymer materials, the shell powder addition amount can reach up to 50 wt%, the surface whitening and agglomeration phenomena are greatly improved, the foaming stability, foaming structure strength, foaming ratio, cutting and processing feasibility are greatly improved, and stable production is possible. More importantly, based on the responsibility of protecting the ecological environment, the present invention treats marine waste (especially shells) and blends them with fully recycled polymer materials to make foaming materials, so as to achieve the recycling of waste and reduce the use of polymer materials such as plastics and rubbers.

S11: Pretreatment step S12: Mixing step S13: Foaming step S14: Cutting step S21: Pretreatment step S22: Modification step S23: Mixing step S24: Foaming step S25: Cutting step S31: Pretreatment step S32: Modification mixing step S33: Mixing and granulation step S34: Mixing step S35: Foaming step S36: Cutting step

FIG. 1 is a manufacturing flow chart of a foam material according to one embodiment of the present invention. FIG. 2 is a manufacturing flow chart of a foam material according to another embodiment of the present invention. FIG. 3 is a manufacturing flow chart of a foam material according to an embodiment of the present invention.

S11: Pre-treatment step

S12: Mixing step

S13: Foaming step

S14: Cutting step

Claims (10)

A foaming composition using marine waste, comprising: fully recycled polymer material; shell powder; coupling agent; foaming agent; bridging agent; and processing aid; wherein, based on the total amount of the foaming composition as 100 wt%, the content of the fully recycled polymer material is 49 to 70 wt%, the content of the shell powder is 29 to 50 wt%, the content of the coupling agent is 0.01 to 3 wt%, the content of the foaming agent is 0.5 to 10 wt%, the content of the bridging agent is 0.25 to 3 wt%, and the content of the processing aid is 0.2 to 15 wt%. A foaming composition as claimed in claim 1, wherein the fully recycled polymer material comprises fully recycled PE. The foaming composition of claim 1, wherein the shell powder comprises shellfish powder, oyster shell powder, mussel shell powder, abalone shell powder, clam shell powder, nine-hole shell powder, rattan pot shell powder, or snail shell powder. The foaming composition of claim 1, wherein the coupling agent comprises a titanium ester. The foaming composition of claim 1, wherein the foaming agent comprises azodicarbonamide. The foaming composition of claim 1, wherein the bridging agent comprises BIBP. The foaming composition of claim 1, wherein, based on the total amount of the foaming composition being 100 wt%, the processing aid comprises: 0.1 to 5 wt% of zinc stearate; 0.1 to 5 wt% of zinc oxide; and 0.03 to 3 wt% of stearic acid. The foaming composition of claim 1 further comprises at least one of a flame retardant, an antistatic agent, a pigment and a softener. A foaming material using marine waste is formed by foaming the foaming composition of any one of claims 1 to 8. The foam material of claim 9, wherein, when the drop height is 60 to 80 cm, the G value of the drop test of the foam material is between 45 and 110 N/kg.

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