KR20120039134A - Injection molded article by using plant biomass powder and method of the same - Google Patents

Abstract

PURPOSE: An environmentally friendly injection-molded product and a manufacturing method thereof are provided to improve natural degradation function and reduce carbon dioxide. CONSTITUTION: A manufacturing method of an environmentally friendly injection-molded product comprises the following steps: manufacturing corn core powder by shattering the corn core to pieces(s11); manufacturing coated corn core powder by adding wax to the dry corn core powder after heat drying the corn core powder(s12); forming a mixture by mixing plastic resin polymer, organic acid, and peroxide with the coated corn core powder(s13); manufacturing pellets by throwing the mixture into an extruder(s14); and manufacturing the environmentally friendly injection-molded product using an injection-molding after adding the pallet to a plastic resin(s15).

Description

Eco-friendly injection molded article using plant biomass and its manufacturing method {Injection molded article by using plant biomass powder and Method of the same}

The present invention relates to an environmentally-friendly injection molded article using plant biomass and a method of manufacturing the same, and more particularly to preparing biomass pellets using corn biomass powder of plant biomass, and then using the pellets to prepare food packaging materials, baby products, bathroom supplies, and the like. The present invention relates to an eco-friendly injection molded product using a biodegradable plant biomass raw material pellet containing corn core powder treated to facilitate the production of industrial packaging materials, and a method of manufacturing the same.

Biomass plastics are plastics containing 25% or more of so-called biomass derived from plants such as corn, and the effect of suppressing the increase in the concentration of carbon dioxide in the atmosphere by using a plant resource in which carbon in the atmosphere is fixed by photosynthesis as a raw material It is possible to reduce the consumption of petroleum, a limited resource, and since it is decomposed by microorganisms after disposal, has recently attracted attention as an environmentally friendly biodegradable material.

Natural decomposition involving biomass occurs in three stages. The first step is the step of microbial decomposition and oxidative decomposition of the biodegradable components, and the physical breakdown of the polymer occurs as the biomass components contained in the final product such as food containers are microbially degraded. As the first step proceeds, the surface area increases, the physical strength and the elongation decrease, and the polymer proceeds to a porous state. The second step is a chemical decomposition (molecular weight reduction) step, the automatic oxidation reaction proceeds by the carboxylic acid, ketones, aldehydes, etc. generated due to the natural decomposition, the surface gradually becomes hydrophilic to promote thermal and chemical decomposition, Chemical decomposition occurs due to peroxides, organic acids and the like, and the molecular weight of the polymer decreases. The third stage is a microbial decomposition (final biodegradation) stage, in which the molecular weight is lowered and the plastic is made into a low molecular weight, changed into alcohol, aldehyde, fatty acid, etc., and then further decomposed into water, carbon dioxide and biomass. Various bacteria, bacteria, enzymes, etc. present in the soil act on the low molecular weight polymer and finally biodegrade in nature. When the molecular weight falls below 40,000, decomposition by the microorganisms proceeds actively without the action of additives or the like. In a real natural environment, the three decompositions proceed simultaneously and complementarily. What is needed is a biodegradable composition to contribute to the decomposition of the first and second stages above.

Corn is a perennial crop belonging to the flower family, and it varies depending on the region. However, it grows well without being affected by drought or rainy season and the soil is not oiled.

The corn core is a sorghum-like part inside the corn stalk, which is one of the biomass. If you use corn core, unlike other natural products, it can be purchased at a low price, has the advantage of easy powdering, and has an excellent decomposition effect. However, unlike other plants, corn core has a low content of fiber, which causes severe carbonization during injection molding, and it is hard to exceed 5% due to poor flowability. Therefore, there is a demand for developing an effective method for increasing the content of corn cores in corn core compositions used for injection molding and using corn cores in large quantities.

The first problem to be solved by the present invention is to disclose a method for producing an eco-friendly injection molded article with a high content of corn core which is one of plant biomass.

Another problem to be solved by the present invention is to disclose an eco-friendly injection molded article with a high content of corn core.

In order to achieve the object of the present invention, (A) grinding the corn core into fine particles of 80 to 400 mesh or less to produce corn core powder (B) heating the corn core powder at 50 degrees to 150 ℃ 0.5 to 24 hours Drying to remove moisture, and adding wax to the heat dried corn core powder and stirring to produce a coated corn core powder (C) a plastic resin polymer and an organic acid serving as a binder to the coated corn core powder; (D) adding the mixture to a twin extruder to produce a mixture by including the peroxide, and mixing the plastic resin-natural plant graft bond, and the plastic resin-natural plant graft bond is formed. The pellet composition is discharged through a discharge port, and blown dry while transferring the discharged strand through a conveyor belt. Manufacturing a biodegradable plant biomass pellet by post-cutting or face-cutting (E) a method for manufacturing an eco-friendly injection molded article, comprising the step of adding the manufactured pellet to a plastic resin and then injection molding the injection molded article To present.

In the step (C), the starch and starch plasticizer is further added before mixing the input, wherein the starch is 100 parts by weight of the plastic resin-natural plant graft bonding structure composition (pellet composition, as follows). It is preferable that it is 5-50 weight part with respect to.

In the step (C), prior to mixing the input is to add any one or more of the lubricant, oxidant and inorganic filler, the lubricant is 0.5 to 100 parts by weight of the plastic resin-natural plant graft bond structure composition To 5 parts by weight, and the oxidizing agent is preferably 0.2 to 6 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition.

The inorganic filler is preferably 10 to 65 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition.

The peroxide is any one of dicumyl peroxide, benzoyl peroxide, di-tributyl peroxide, and the content of the peroxide is preferably 0.01 to 5.0 parts by weight based on 100 parts by weight of the plastic resin.

The organic acid is any one or more of citric acid, malic acid, malic acid and acetic acid, the content of the organic acid is preferably 0.2 to 5 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition.

The glidants may be used without limitation, those generally known, and specifically, one or more of zinc stearate and calcium stearate, and the oxidizing agent is any one or more of oleic acid, linoleic acid, linolenic acid, arachidonic acid, and palmitoleic acid, The inorganic filler is preferably one or more of calcium carbonate, clay, talc and loess.

The starch plasticizer is any one or more of glycerin and sorbitol, the content of the starch plasticizer is preferably 10 to 30 parts by weight based on 100 parts by weight of the starch based on the starch content.

The peroxide is dicumyl peroxide, and the dicumyl peroxide content is preferably 0.01 to 5.0 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition.

The content of the corn core is 10 to 50 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition, the combined content of the corn core and starch is increased as the content of the plastic resin increases The content of the peroxide is increased as the content of the plastic resin is increased, and the content of the organic acid is preferably increased as the combined content of the corn core and starch is increased.

The binder resin of step (C) is any one of linear low density polyethylene (LLDPE), low density polyethylene (LDPE), high density polyethylene (HDPE), polypropylene (PP), polystyrene (PS) and acrylonitrile butadiene styrene (ABS) It is preferable that it is above.

The binder resin is preferably a pellet having a melt index of 3.0 or more.

Preferably, the coating step of step (B) and the step (C) are performed at the same time.

In order to achieve the object of the present invention, it proposes an environment-friendly injection molded article manufactured by the above-described manufacturing method.

Eco-friendly injection molded article prepared in accordance with the present invention can be produced by using a large amount of corn-core powder is not only excellent in the biodegradability of the injection molded article manufactured, but also to produce an eco-friendly injection molded article with reduced carbon dioxide.

Figure 1 is an exemplary flow diagram for a method for manufacturing an environmentally-friendly injection molded article using the plant biomass of the present invention.
Figure 2 is a schematic diagram that the plastic resin-natural plant graft bond structure is produced.
3 is a SEM photograph of a pellet fragment in which the graft bonding structure is not produced and a SEM photograph of the pellet fragment in which the graft bonding structure is produced.
4 is a schematic diagram of the plastic resin-natural plant graft coupling reaction point.

Hereinafter, it demonstrates in detail, referring drawings.

1 is an exemplary flow chart of a method for manufacturing an eco-friendly injection molded article of the present invention.

The present invention is largely divided into five steps of a method for producing a biodegradable corn core pellet. The first step is a step (S11) of grinding the corn core to produce corn heart powder. Corn cores are pulverized into fine powder so as to be about 80 to 400 mesh. If the size is less than 80 mesh, the particle size is so large that the productivity is poor due to poor flowability during pellet production, the surface is rough, and the quality of the final product, such as film, is deteriorated, the strength of the product is worsened, Due to the very small size, the product quality is excellent, but the grinding time is too long, which lowers the price competitiveness due to lower overall productivity and higher costs.

Subsequently, the corncob powder is coated with wax to produce a coated corncob powder (S12). In the coating step, the corn core powder is dried by heating at 50 ° C. to 150 ° C. to remove moisture, and wax is added to the heat dried corn core powder and stirred to produce a coated corn core powder. Drying is carried out for 0.5 to 24 hours while heating and stirring at 50 ℃ ~ 150 ℃ using a conventional drying apparatus to dry to less than 10% moisture content. If the drying temperature is less than 50 ℃, there is a problem that does not dry enough, or takes a long time to dry, and if it exceeds 150 ℃ there is a problem that the likelihood of carbonization of corn cores and the like increases the quality of the product. If the drying time is less than 0.5 hours, there is a problem that the product quality is bad due to moisture problems when producing the product by applying the finished product is not enough, and if more than 24 hours there is a problem that only energy is wasted without additional drying effect. Wax is added to the dried corn core powder and the corn core surface is coated by high speed stirring at 300 to 800 rpm. The added wax is dissolved by self heating (self-heating) and coated on the surface of the corn core. The coated corn core powder is prevented from reabsorbing moisture. Wax has the advantage of low molecular weight and low melting point can also perform the function as a lubricant aid when preparing the additive composition using an extruder, and also has the advantage of being biodegradable into a low molecular weight material. Waxes may be used paraffin wax, liquid paraffin wax, beeswax, drive wax, emulsion wax, candelilla wax, PE wax, PP wax and the like. The wax content is preferably 1% to 20% of the corn core content. When used less than 1%, the lubricant has a weak role, and when used more than 20%, debris such as debris occurs in the die, the cost increases. If a lot of wax is used, the coating for water resistance is excellent, but since it causes debris on the production equipment dies in injection, extrusion, film production, etc. later, the productivity may be deteriorated, thus, 1 to 100 parts by weight of the plastic resin-corn core graft bonded structure composition. It is better to use 5 parts by weight.

In the coating step, the wax is added and then stirred at high speed at 300-800 rpm. Thus, the wax is naturally melted by the self-heating by the high speed stirring, and the surface of the corn core powder is coated. The coating time is not specified, and the coating finishes the coating in that the corn core is somewhat lump-shaped. In general, the coating is completed in a little lump form in about 10 to 30 minutes.

Subsequently, a plastic resin polymer, an organic acid, and a peroxide, including binders are added to the coated corn core powder and mixed (S13), and a graft bond is formed to form pellets (S14). Peroxides chemically cut the polymer chains of plastic resins. The organic acid serves as an intermediate for binding corn cores to some cleaved plastic resin polymer terminal groups. 2 shows this schematic diagram. The peroxide and the organic acid form the plastic resin-corn core graft bond structure shown in FIG. 2. The organic acid binds to the polymer terminal group cut by the peroxide. The peroxide is preferably the peroxide is any one of dicumyl oxide, benzoyl peroxide, di- triple butyl peroxide. Peroxides include azo-bis-isobutylnitrile, tributyl hydroperoxide, dicumyl peroxide, 2,5 dimethyl-2,5 di (thibutylperoxy) hexane (2,5-Dimethyl-2,5- di (t-butyl peroxy) hexane), 1,3-bis (ti-butylperoxy-isopropyl) benzene (1,3-Bis (t-buthyl peroxy-isoproply) benzene), etc. may also be used, but the experimental results Mill oxide, benzoyl peroxide, di-triple butyl peroxide was good, the graft bond structure of the corn core and the plastic polymer of dicumyl oxide was most preferred, the finished product productivity such as film was the best.

The content of the peroxide may be 0.01 to 5 parts by weight based on 100 parts by weight of the plastic resin based on the plastic resin. However, if it is 0.01 parts by weight or less, it is difficult to expect graft bonding and commercialization functions, so that the corn core content of the final product is reduced, and the natural decomposition period of the plastic resin is reduced, resulting in a long period of final decomposition. have. On the other hand, if you use more than 5 parts by weight, the cost increases a lot, there is a problem that the economy is insufficient. Preferably, it is preferable to use 0.01 part by weight or more and less than 0.5 parts by weight with respect to 100 parts by weight of the plastic resin-natural plant graft bonding structure composition (pellet composition, as follows).

The organic acid binds to the polymer terminal group cut by the peroxide and serves as an oxidative decomposition agent. The organic acid is preferably one or more selected from citric acid, malic acid, maleic acid, maleic acid, acetic acid, and the content of the organic acid is the plastic resin-natural plant graft bond. It is preferable to use 0.2 weight part or more and less than 5 weight part with respect to 100 weight part of structure compositions. When the content of the organic acid is less than 0.2 parts by weight, the oxidative decomposition function of the plastic resin is weakened, and when it exceeds 5 parts by weight, there is a burden of cost increase.

Corn core, unlike other plants, has a bad property of producing a biodegradable injection molded product with a composition containing corn core, the corn core content in the conventional corn core composition for production of injection products was difficult to exceed 5%. If graft bonding is sufficient, the productivity of finished products such as sheet production and extrusion molding as well as injection molding can be improved, and the content of materials with poor physical properties such as corn core can be increased.

Graft bonding occurs well when extruders such as twin extruders react at screw speeds of 200 to 600 rpm at temperatures of 100 to 200 ° C. If the reaction temperature is 100 ℃ or less, the added raw materials do not melt and can not react, and if it is 200 ℃ or more, carbonization occurs, or the temperature is too high to melt the resin like water and make it into a pellet.

Meanwhile, starch may be further added to the input as one of the biodegradable plants. The reason for adding more starch is 1) the highest biodegradability among vegetable biomass, 2) cheaper than other raw materials, 3) resource abundance and ease of supply, 4) non-toxicity of raw materials, 5) plasticization This is because it is easy to paint and has excellent physical properties such as plastic. When starch is added, it is preferable to add an additional starch plasticizer. When the starch plasticizer is added, the starch plasticizer is modified at high temperature and high pressure to change the properties of the starch into thermoplastic starch, thereby improving molding processability when producing a finished product (film, injection, extruded product). If the starch plasticizer is not added, even if the finished product is produced, the physical properties of the product deteriorate due to flowability, moldability, and carbonization. Starch is also a naturally degradable plant, such as corn core, so that the plastic resin-starch graft bond structure shown in FIG. The plastic resin-corn graft bond structure and the plastic resin-starch graft bond structure are collectively referred to as a plastic resin-natural plant graft bond structure. It will be apparent that corn core powder and starch may be simultaneously bound to the plastic resin chain, and a schematic diagram of the plastic resin-natural plant graft bonding structure is shown in FIG. 3. The starch plasticizer is suitably 10% to 30% by weight of the starch weight. If it is less than 10%, starch denaturation is not easy, and if it exceeds 30%, the price is high and economic efficiency is low.

Higher plant biomass content in the final product is desirable in terms of lower carbon dioxide emissions. Corn cores are not suitable for adding high amounts to finished products due to poor physical properties such as elongation and strength. Location is important. The particle size of the starch is fine because the starch can be plasticized and used as a thermoplastic starch. Starch materials can vary, but the properties of underground starch (potato starch, potatoes, tapioca, etc.) are better. However, there is a problem that the price is too expensive in Korea. As an alternative to this, ground starch (corn, wheat, rice starch, etc.) may be used. Corn is preferable because of various conditions.

In addition, an oxidant is additionally added to accelerate decomposition of the polymer material such as plastic resin and the like and to promote thermal decomposition and photolysis. The oxidizing agent may be used as oleic acid, linoleic acid, linolenic acid, arachidonic acid, palmitoleic acid, etc. as an unsaturated fatty acid series. The amount of the oxidizing agent added is preferably 0.2 part by weight or more and less than 6 parts by weight with respect to 100 parts by weight of the plastic resin-natural plant graft bond structure composition. If the amount of the oxidizing agent is less than 0.2 part by weight, the oxidative decomposition function of the polymer material such as plastic resin is weak, and when used in excess of 6 parts by weight, there is a problem in that the product properties are lowered and the productivity deteriorates when the product is produced.

Since natural plants have low molecular weight and low melting point, there is a problem of poor flowability in the production of pellets. The plastic resin-natural plant graft bonding structure composition may further include a lubricant as it is necessary to improve the flowability when using the natural material / plant material to enable smooth production of the pellets. Suitable lubricants are zinc stearate and calcium stearate. The lubricant is preferably used in an amount of 0.5 parts by weight or more and less than 5 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition. When the amount is less than 0.5 parts by weight, the lubricant has a weak role, and when used in excess of 5 parts by weight, debris such as debris occurs in the die, and the cost increases.

In addition, the plastic resin-natural plant graft bonding structure composition may further include an inorganic filler. The content of the inorganic filler is preferably 10 parts to 65 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition. When the inorganic filler is used in less than 10 parts by weight, the cost reduction is less affected, and when using more than 65 parts by weight, the physical properties such as tensile strength, elongation of the product.

The powdery mixture produced through the above process is completed. Since such a composition is in a powder state, a material that serves as a binder for tangling the powder is required. The plastic resin used as the binder material may be linear low density polyethylene (LLDPE), low density polyethylene (LDPE), high density polyethylene (HDPE), polypropylene (PP), polystyrene (PS) and acrylonitrile butadiene styrene (ABS). . The binder may be used in an amount of 15 parts by weight to 60 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition. If the content of the binder is less than 15 parts by weight, there is a risk that the finished pellets are fragile or cracked, and if the content of the binder exceeds 60 parts by weight, the economical efficiency of the finished pellets is lost.

The corn core pellets according to the present invention may be molded into a product to be manufactured by injection, injection molding, extrusion molded article, etc. by mixing immediately with a conventional thermoplastic polymer resin such as plastic and other composition components according to the application. Alternatively, the required thermoplastic polymer resin and the other components may be mixed in an appropriate ratio according to the use to prepare a compound in advance, and then may be molded back into a desired product if necessary.

Subsequently, a mixture of the above materials and the like is discharged through an ejection opening using a plastic resin-natural plant graft bond using an extrusion apparatus such as a twin-screw extruder, and the blown strand is transported through a conveyor belt while being blown through the conveyor belt, and then cut. Or pellets are prepared by face cutting.

Finally, the pellet is mixed with a conventional thermoplastic polymer resin on the fly to prepare an environment-friendly injection molded article of the present invention (S15). In this case, the thermoplastic polymer resin to be mixed is preferably the same kind as the binder resin used at the time of pellet production. For example, when PP is used in the production of the pellets, it is preferable that the resin to be mixed when injecting the injection molded article is also PP. This is because the same kinds of resins are mixed well. For example, when PP is used as the binder resin, the pellets and PP may be mixed to produce a product. If the binder resin of the pellet is ABS, ABS may be mixed to produce the product. On the other hand, the binder resin is injected with a mixture of pellets and PP of ABS, ABS and PP do not mix, so the quality is very bad, there is no product value. On the other hand, polyolefin series, that is, PP, LLDPE, HDPE, and some LDPE are the same polyolefin series, so even when mixed and injected, the product comes out well.

On the other hand, in the case of 100% general PP, the injection pressure is appropriate if the injection pressure is about 30bar at the injection temperature of 240 ° C, but when mixing 30 parts by weight of oxime pellets and 70 parts by weight of the general PP, the injection pressure is about 65bar at the injection temperature of 240 ° C. High is good The temperature does not change much, but because the flowability (MI, Melt Index) is lowered, it is necessary to increase the injection pressure so that the injection is performed properly without forming.

Hereinafter, the present invention will be described in more detail by way of examples. The following examples are intended to illustrate the invention and are not intended to limit the invention thereto.

<Examples 1-8>

Preparation of Biodegradable Plant Biomass Pellets

&Lt; Example 1 >

Corn core was pulverized to about 150 mesh to produce corn core powder, and then heated and dried at 100 ° C. for 30 minutes to prepare dried corn core powder. 1.5 parts by weight of LC wax 102N (Lion Chemical) was added to the dried corn core powder, and the corn core surface was coated by high speed stirring at 500 rpm. 100 parts by weight of the plastic resin-natural plant graft bond structure composition, 25 parts by weight of surface-coated corn core powder, 25 parts by weight of polypropylene, 10 parts by weight of linear low density polyethylene (LLDPE), 20 parts by weight of corn starch, sorbitol 4 parts by weight, linoleic acid 0.3 part by weight, zinc stearate 1 part by weight, maleic acid 0.5 part by weight, dicumyl peroxide 0.01 part by weight and the remainder was added to a high-speed stirrer with calcium carbonate and stirred at 400 rpm to produce a mixture, Biodegradable plant biomass pellets were prepared using a twin screw extruder.

<Example 2>

30 parts by weight of corn core was added in Example 1, and the same composition for pellets was produced as in Example 1 except that 0.02 part by weight of dicumyl peroxide was produced to prepare pellets.

<Example 3>

Except 35 parts by weight of corn core in Example 1, 0.03 parts by weight of dicumyl peroxide was added to produce the same composition for pellets as in Example 1, to prepare a pellet.

 <Example 4>

40 parts by weight of corn core was added in Example 1, except that 0.04 parts by weight of dicumyl peroxide was added to produce the same composition for pellets as in Example 1 to prepare pellets.

Example 5

In Example 1, 0.5 parts by weight of citric acid was added instead of 0.5 parts by weight of maleic acid, and 0.02 parts by weight of benzoyl peroxide was added instead of 0.01 parts by weight of dicumyl peroxide to produce the same composition for pellets as in Example 1. To prepare pellets.

 <Example 6>

In Example 5, except that 30 parts by weight of corn core and 0.03 parts by weight of benzoyl peroxide, the same composition for pellets as in Example 6 was produced to prepare pellets.

 <Example 7>

In Example 5, 35 parts by weight of corn core was added, except that 0.04 parts by weight of benzoyl peroxide to produce the same composition for pellets as in Example 6, to prepare a pellet.

 <Example 8>

  In Example 5, except that 40 parts by weight of corn core and 0.05 parts by weight of benzoyl peroxide, the same composition for pellets as in Example 6 was produced to prepare pellets.

Comparative Example 1

In Example 1, except that 0.5 parts by weight of maleic acid, 0.01 parts by weight of dicumyl peroxide was subtracted to produce the same composition for pellets as in Example 1, to prepare a pellet.

Comparative Example 2

In Example 5, except that 0.5 parts by weight of citric acid and 0.02 parts by weight of benzoyl peroxide was removed, the same composition for pellets as in Example 5 was produced to prepare pellets.

<Examples 9-16>

Eco-Friendly Injection Molding

Example 9

 30 parts by weight of the pellets prepared in Example 1 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Hunan Petrochemical products

<Example 10>

 30 parts by weight of the pellets prepared in Example 2 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Hunan Petrochemical products

<Example 11>

 30 parts by weight of the pellets prepared in Example 3 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Hunan Petrochemical products

<Example 12>

30 parts by weight of the pellets prepared in Example 4 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Hunan Petrochemical products

Example 13

30 parts by weight of the pellets prepared in Example 5 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Hunan Petrochemical products

<Example 14>

 30 parts by weight of the pellets prepared in Example 6 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Honam Petrochemical.

<Example 15>

 30 parts by weight of the pellets prepared in Example 7 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Honam Petrochemical.

<Example 16>

 30 parts by weight of the pellets prepared in Example 8 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Honam Petrochemical.

<Example 17>

 30 parts by weight of the pellets prepared in Comparative Example 1 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Honam Petrochemical.

&Lt; Example 18 >

 30 parts by weight of the pellets prepared in Comparative Example 2 and 70 parts by weight of polypropylene (PP) were mixed, and then injection molded products were manufactured using a conventional injection molding machine. PP used Honam Petrochemical.

Experimental Example 1

Mechanical Properties Testing of Eco-Friendly Injection Molded Products Prepared According to Examples 9-18

Tensile strength and elongation were measured for samples cut to 25 × 102 mm according to ASTM D 3826 for the injection molded articles prepared in Examples 9-18. In order to reduce the measurement error, the number of injection molded samples was measured 10 times for each measurement item and the average value was taken out of the maximum and minimum values. Load cell was used 50kg and UTM (Universal Testing Machine, Daekyung Tech, Korea) machine was used, the tensile speed of the machine was set to 50mm / min, the experiment was carried out, the results are summarized in Table 1 below.

Mechanical property test result division Tensile Strength (㎏ / ㎠) Elongation (%) PP products 280 200 Example 9 280 201 Example 10 278 196 Example 11 271 193 Example 12 270 191 Example 13 277 200 Example 14 276 195 Example 15 270 192 Example 16 270 189 Example 17 267 178 Example 18 265 176

As can be seen from Table 1, the injection molded product using a corn core, one of the plant biomass according to the present invention can be seen that the tensile strength and elongation is similar to the existing product despite the inclusion of corn cores, organic acids, peroxides, etc. . In Examples 17 and 18 corresponding to Comparative Examples 1 and 2, it can be seen that the tensile strength and the elongation are lower than those of Examples 9 to 16, which correspond to the existing products or examples of the present invention.

Experimental Example 2

Evaluation of Photodegradability of Eco-friendly Injection Molded Products Prepared According to Examples 9-18

Photodegradation was performed by irradiating ultraviolet rays for 200 hours using a QUV Accelerated Weathering Tester according to ASTM D15 UV treatment test method, and then measuring the tensile strength and elongation of the injection molded article. At this time, the type of ultraviolet (UV) lamp was UVB 313, the light intensity (Irradiance) was 0.60w / nf (310nm) and the results are shown in Table 2 below.

Photodegradability Test Results division Strength retention rate (%) % Retention PP products 97.3 96.7 Example 9 2.5 1.6 Example 10 0.9 0.5 Example 11 0.7 0.1 Example 12 0.5 0.0 Example 13 3.2 1.8 Example 14 1.3 0.9 Example 15 1.1 0.5 Example 16 0.7 0.2 Example 17 37.2 32.8 Example 18 38.0 34.1

  As can be seen from Table 2, the strength retention and elongation retention of the conventional PP products are hardly reduced even after UV irradiation, whereas the injection molded articles to which corn core pellets according to the present invention are significantly reduced in strength retention and elongation retention. It became. In Examples 17 to 18 without using an organic acid and a peroxide, strength and elongation were reduced by more than 60% compared to the PP product. That is, it can be seen that the injection molded article of the present invention can be decomposed to a considerable extent in a natural state by light such as ultraviolet rays. In addition, it can be seen that as the corn core content increases, the degree of degradation increases.

<Experimental Example 3>

Evaluation of Biodegradability of Eco-friendly Injection Molded Products Prepared According to Examples 9-18

Evaluation of biodegradability by mold of injection molded articles made from pellets using corn cores of the plant biomass of the present invention was tested according to the ASTM G 21 method. That is, the AAS that after cutting the sample to a predetermined size by using a solid agar medium without a carbon source as a medium commonly found in the soil and this switch Aspergillus (Aspergillus niger), Penny room Solarium Pinot pilreom (Penicillium piniphilum), while tomyum Globo island (Chaetomium globosum), glycidyl Eau radium as by lances (Gliocladium virens), and Aureobasidium pullulans (every 10 days the degree of mold covered a period of 60 days a sample of mixed fungal spore suspension was sprayed on the sterility of the Aureobasidium pullulans) ASTM G 21 method The biodegradability was measured according to the evaluation.

In addition, the biodegradability evaluation by bacteria was tested according to the ASTM G 22 method. A cell mixture suspension of Pseudomonas aeruginosa and Baccllus subtillus was applied to the sample in a sterile state on a solid agar medium without a carbon source. The biodegradability was measured according to the evaluation and summarized in Table 3.

Biodegradation Notation Method Growth in Observed Samples Rating none 0 Growth traces (less than 10%) One Slight growth (10-30%) 2 Medium growth (30-60%) 3 Overgrowth (60%? Completely covering the surface) 4

 At the same time, the sample of the eco-friendly injection molded product is taken out every 20 days while being kept in a constant temperature and humidity chamber fixed at a relative humidity of 85% and an internal temperature of 30 ° C. It was measured by the ratio.

In the case of bacteria, the relative humidity was fixed at 85% and the internal temperature of 37 ° C., and the weight loss was measured in the same manner as described above.

The results are shown in Tables 4 and 5 below.

Evaluation of biodegradation by mold and weight loss test results division Biodegradation degree (%) Weight loss rate (%) ^* 10 days 20 days 30 days 40 days 50 days 60 days 20 days 40 days 60 days PP products 0 0 0 0 0 0 99.9 99.9 99.9 Example 9 One 2 2 3 4 4 94.3 74.2 58.3 Example 10 One 2 3 4 4 4 93.2 71.6 52.1 Example 11 One 2 3 4 4 4 92.8 68.3 50.3 Example 12 2 3 3 4 4 4 91.2 63.2 47.7 Example 13 One 2 2 3 4 4 95.6 74.6 61.7 Example 14 One 2 3 3 4 4 94.8 72.2 55.4 Example 15 One 2 3 4 4 4 93.3 69.4 51.7 Example 16 2 3 3 4 4 4 92.8 64.2 50.7 Example 17 One 2 2 2 3 3 96.2 78.4 67.5 Example 18 One 2 2 2 3 3 96.9 78.3 68.0

^* Weight loss rate (%) = weight after sampling / weight of original sample × 100

Evaluation of the degree of biodegradation by bacteria and weight loss test results division Biodegradation degree (%) Weight loss rate (%) ^* division 10 days 20 days 30 days 40 days 50 days 60 days 20 days 40 days 60 days PP products 0 0 0 0 0 0 99.9 99.9 99.9 Example 9 One 2 2 3 4 4 95.2 73.4 57.7 Example 10 One 2 3 3 4 4 93.9 72.1 53.4 Example 11 One 2 3 4 4 4 92.5 69.6 51.5 Example 12 2 3 3 4 4 4 90.9 63.1 48.9 Example 13 One 2 2 3 4 4 96.1 75.8 62.4 Example 14 One 2 3 3 4 4 94.9 73.3 55.4 Example 15 One 2 3 4 4 4 92.2 69.7 53.9 Example 16 2 3 3 4 4 4 91.0 64.4 51.4 Example 17 One 2 2 2 3 4 96.7 79.2 68.4 Example 18 One 2 2 2 3 3 97.0 78.8 68.1

As can be seen from Tables 4 and 5, the existing PP products are hardly decomposed by bacteria or mold, and in the case of Examples 17 to 18 where organic acids and peroxides are not used, partial decomposition proceeds. It became. Eco-friendly injection molded article according to the present invention can be seen that significantly progressed by the bacteria and mold over time. In addition, if the corn core content is high it can be seen that the growth of bacteria and fungi.

The present invention can be used in various manufacturing industries, such as carbon dioxide reduction, biomass plastics industry by replacing plastics.

S11: (A) step: corn core powder generation
S12: (B) step: corn core powder coating
S13: (C) step: forming a mixture by adding a binder, organic acid, peroxide, etc.
S14: (D) step: plastic resin-natural plant graft bonding and pellet molding
S15: (E) step: manufacturing injection molded articles

Claims (10)

(A) pulverizing the corn core into fine particles of 80 to 400 mesh or less to produce corn core powder;
(B) drying the corn core powder at 50 ° C. to 150 ° C. for 0.5 to 24 hours to remove moisture, and adding wax to the heat dried corn core powder and stirring to produce a coated corn core powder;
(C) forming a mixture by adding and mixing a plastic resin polymer and an organic acid and a peroxide serving as a binder to the coated corn core powder;
(D) the mixture is introduced into an extruder to form a plastic resin-natural plant graft bond, and the pellet composition including the plastic resin-natural plant graft bond is discharged through an outlet, and the discharged strand is conveyed. Pellet manufacturing step of manufacturing pellets by cutting or face-cutting after blowing air while transferring through the belt;
(E) injection molding by adding the prepared pellets to the plastic resin to produce an environmentally-friendly injection molded article; manufacturing method of an environmentally-friendly injection molded article comprising a. The method of claim 1,
In the step (C), the starch and starch plasticizer is further added before mixing the input,
The starch is 5 to 50 parts by weight based on 100 parts by weight of the pellet composition,
The starch plasticizer is one or more of glycerin and sorbitol,
The starch plasticizer content is 10 to 30 parts by weight with respect to 100 parts by weight of the starch, based on the starch content manufacturing method of the injection-molded article.
The method of claim 1,
In the step (C), it is to add any one or more of the lubricant, oxidant and inorganic filler before mixing the input,
The lubricant is 0.5 to 5 parts by weight based on 100 parts by weight of the pellet composition,
The oxidizing agent is 0.2 to 6 parts by weight based on 100 parts by weight of the pellet composition,
The inorganic filler is 10 to 65 parts by weight based on 100 parts by weight of the pellet composition,
The lubricant is one or more of zinc stearate and calcium stearate,
The oxidizing agent is any one or more of oleic acid, linoleic acid, linolenic acid, arachidonic acid and palmitoleic acid,
The inorganic filler is a method for producing an environmentally-friendly injection molded article, characterized in that any one or more of calcium carbonate, clay and loess.
The method of claim 1,
The peroxide is any one of dicumyl oxide, benzoyl peroxide, di- triple butyl peroxide,
The content of the peroxide is 0.01 to 5 parts by weight based on 100 parts by weight of the plastic resin manufacturing method of eco-friendly injection molding.
The method of claim 1,
The organic acid is one or more of citric acid, citric acid, malic acid, maleic acid, maleic acid, acetic acid,
The amount of the organic acid is 0.2 to 5 parts by weight based on 100 parts by weight of the pellet composition.
The method of claim 1,
The wax is any one or more of paraffin wax, liquid paraffin wax, beeswax, molda wax, emulsion pile wax, P. wax, P. wax.
The wax content is a method for producing an environmentally-friendly injection molded article, characterized in that 1.0 to 5.0 parts by weight based on 100 parts by weight of the pellet composition.
The method of claim 1,
In the step (C), the starch is further added before mixing the input,
The amount of corn core is 10 to 50 parts by weight based on 100 parts by weight of the plastic resin-natural plant graft bond structure composition,
The sum of the contents of the corn core and starch is increased as the content of the plastic resin increases,
The content of the peroxide is increased as the content of the plastic resin increases,
The content of the organic acid is a method of producing an eco-friendly injection molded article, characterized in that it increases as the combined content of the corn core and starch.
The method of claim 1,
The plastic resin of the binder role is at least one of linear low density polyethylene (LLDPE), low density polyethylene (LDPE), high density polyethylene (HDPE), polypropylene (PP), polystyrene (PS) and acrylonitrile butadiene (ABS). Eco-friendly injection molded product manufacturing method.
The method of claim 1,
When the injection molding of the step (E) (D) the pellet is a method for producing an injection-molded article, characterized in that 10 to 200 parts by weight based on 100 parts by weight of the plastic resin.
Eco-friendly injection molded article prepared by the method of any one of claims 1 to 9.

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