CN113698743A

CN113698743A - Biodegradable environment-friendly material, preparation method and application

Info

Publication number: CN113698743A
Application number: CN202111059012.8A
Authority: CN
Inventors: 常忱
Original assignee: Beijing Canglang Zhiyuan Technology Co ltd
Current assignee: Beijing Canglang Zhiyuan Technology Co ltd
Priority date: 2021-09-10
Filing date: 2021-09-10
Publication date: 2021-11-26

Abstract

The invention relates to a biodegradable high molecular material and inorganic powder in-situ polymerization technology, in particular to a biodegradable environment-friendly material which can be biologically, incinerated and photo-oxidized, a preparation method and application thereof, wherein the molecular structure of the biodegradable environment-friendly material is a reticular molecular structure with interpenetrating sea phase and island phase, and the preparation method comprises the following steps: 45 to 50 weight percent of inorganic powder, 45 to 55 weight percent of PBAT resin and 0.675 to 1.5 weight percent of surfactant. 1. Inorganic powder is introduced as a filler, so that the original mechanical strength of the PBAT material is improved, and the raw material cost is greatly reduced; 2. the organic silicon surface modifier is introduced into the sea-island structures of the continuous phase and the disperse phase, so that the compatibility of inorganic powder and PBAT is improved, and the ductility and the elongation at break of the modified material are improved compared with those of the original PBAT material; 3. the negative pressure suction process solves the problems of acidolysis and air bubbles of calcium carbonate in the mixed material at high temperature, and solves the defects of the finished product of film blowing molding and injection molding; the degradation difficulty of PBAT is improved and the degradability is up to more than 90 percent.

Description

Biodegradable environment-friendly material, preparation method and application

Technical Field

The invention relates to a biodegradable high polymer material and inorganic powder in-situ polymerization technology, in particular to a biodegradable environment-friendly material with various degradation effects of biology, incineration and photo-oxidation, a preparation method and application.

Background

The degradable plastic is a plastic which has various properties meeting the use requirements, has unchanged performance in the preservation period and can be degraded into substances harmless to the environment under the natural environment condition after use. There are a variety of new plastics: photodegradable plastics, biodegradable plastics, photo-, oxidation/full-biodegradable plastics, carbon dioxide-based biodegradable plastics, and thermoplastic starch resin degradable plastics.

The polymer material can slowly decompose and age under the photo-oxidative condition, and the photo-oxidative degradation mechanism of the plastic is to introduce a photosensitive group into a polymer structure, for example, the polymer material can be used as a synthetic raw material or an added degradation agent; the photosensitive group generates free radicals after absorbing ultraviolet rays, and promotes the high polymer material to be oxidized and deteriorated under the action of oxygen in the air, so that the degradation speed of the material is greatly accelerated.

PBAT belongs to thermoplastic biodegradable plastic, is a copolymer of butanediol adipate and butanediol terephthalate, has the characteristics of PBA and PBT, and has better ductility and elongation at break as well as better heat resistance and impact property; in addition, the biodegradable polyester film also has better biodegradability. The inventors of the present invention found that the application of PBAT to degradable materials has the following problems: 1. the use cost is high, the selling price is 2-3 times of that of the conventional PE material, and the market capacity is limited; 2. the existing PBAT material has lower mechanical properties, especially lower tensile and puncture strength; 3. the existing PBAT material processing technology has the problem of degraded gas production and unsmooth exhaust when processing fillers such as calcium carbonate and the like, which causes the reduction of the mechanical property of the material.

Disclosure of Invention

Under the action of high temperature and high pressure, PBAT resin and calcium carbonate micropowder are degraded by the traditional extrusion process to generate hollow bubbles, and the specific reason is that the local pressure and temperature of the extrusion process are too high, and organic acid generated by degradation of the PBAT resin further reacts with calcium carbonate to generate carbon dioxide gas, so that the structure and performance of the material are reduced. By improving kneading reaction conditions such as air pressure and vacuum degree, the void ratio of the membrane is greatly reduced, and the mechanical property of the membrane is improved.

In order to solve at least one problem mentioned in the background art, an object of an embodiment of the present invention is to provide a biodegradable environment-friendly material and a preparation method thereof, which solve the problems of high cost, insufficient crystallinity, low melt strength, difficult upper blown film forming, single degradation mode and insufficient mechanical properties of the existing PBAT resin material. The PBAT resin is polymerized with the modified inorganic powder, and the modified inorganic powder has crystallization effect, so that the crystallinity and the solution strength are increased, and the problem of difficult film blowing forming process of the PBAT resin is solved. By adopting the unique kneading process, the problem that the traditional extrusion process degrades PBAT resin and calcium carbonate micro powder under the action of high temperature and high pressure to generate cavity bubbles to influence the film forming quality is avoided.

A biodegradable, environmentally friendly material comprising: 45 wt% -50 wt% of inorganic powder, 45 wt% -55 wt% of PBAT resin and 0.675 wt% -1.5 wt% of surfactant; the biodegradable environment-friendly material has a reticular molecular structure with two interpenetrating phases of a sea phase structure and an island phase structure; the modified inorganic powder is obtained by modifying the inorganic powder through the surfactant, the island phase structure is composed of the modified inorganic powder, and the reticular molecular structure is formed by repeatedly linking, winding and kneading the modified inorganic powder and the PBAT resin.

Preferably, the inorganic powder comprises calcium carbonate, magnesium carbonate and calcium silicate; the particle size of the inorganic powder is more than 3000 meshes.

Preferably, the environment-friendly material further comprises: 0.225 to 0.5 weight percent of dispersant, 0.45 to 1 weight percent of lubricant, 0.225 to 0.5 weight percent of antioxidant and 0.225 to 0.5 weight percent of compatibilizer.

Preferably, the compatibilizer comprises ADR.

Preferably, the surfactant comprises a silicone material.

Preferably, the organosilicon material comprises at least one of liquid hexamethyldisilazane, n-octadecyltrichlorosilane, and hexadecyltrimethoxysilane.

On the basis of the prior art, a preparation method of a biodegradable environment-friendly material is disclosed, which adopts a kneading process, is wholly in a normal air pressure or negative pressure environment, and comprises the following steps:

step 1, conveying inorganic powder into a heat-conducting oil heating type high-speed reaction kettle, taking a surfactant as a modifier, and repeatedly performing collision friction on the inorganic powder in a high-speed vortex form to perform reaction modification treatment on the inorganic powder to obtain second inorganic powder; the exterior of the second inorganic powder body is provided with a surfactant modified layer;

step 2, adding PBAT into the high-speed reaction kettle, and performing linking winding on the PBAT and the second inorganic powder to prepare a first polymer;

step 3, conveying the polymer I to a kneading machine, and performing eutectic kneading treatment to obtain a polymer II with a sea-island molecular structure; wherein the pressure in the kneader is negative pressure;

and 4, conveying the second polymer to a surface mill hot cutting granulating chamber for granulation, cooling in an indirect water-cooling drum cooler, screening to obtain a first particulate matter, and carrying out vacuum packaging and storage on the first particulate matter to obtain the biodegradable environment-friendly material.

Preferably, the modification treatment time in the step 1 is 15min-20 min; the temperature of the chain connection winding in the step 2 is 160-180 ℃, and the time is 30-40 min; in the step 3, the kneading speed of the paddle is 100r/min-120r/min, the kneading time is 30min-40min, and the kneading temperature is 150-180 ℃; the negative pressure in the step 3 is 100-1.01 multiplied by 10⁵Pa。

On the basis of the prior art, the application of the biodegradable environment-friendly material is disclosed, the environment-friendly material or the biodegradable environment-friendly material prepared by the method is made into a material film product through calendering, blow molding or biaxial stretching; or the biodegradable environment-friendly material is extruded, blow-molded or injection-molded to form a material plate or a container.

Preferably, the transverse tensile strength of the material film product is more than or equal to 19.5MPa, the longitudinal tensile strength is more than or equal to 22.3MPa, the transverse elongation at break is more than or equal to 518%, and the longitudinal elongation at break is more than or equal to 490%.

The calcium carbonate serves as a buffering agent component in the degradation process of the PBAT material, effectively promotes the pH stability of the surface of a degradation unit, is beneficial to the growth of alkalophilic bacteria, and prevents the reduction of aerobic respiration efficiency caused by the growth of anaerobic bacteria with too low pH, thereby causing the reduction of the degradation rate of the whole compost. Compared with other acid inert fillers, the silicate taking calcium carbonate, magnesium carbonate and the like as main materials has remarkable promotion effect on the aerobic composting degradation of PBAT materials.

The invention provides a biodegradable environment-friendly material and a preparation method thereof, and the biodegradable environment-friendly material has the following characteristics: 1. inorganic powder is introduced as a filler, and the tensile property of the calcium carbonate/PBAT composite material tends to be reduced after being improved, because the low addition amount of calcium carbonate does not generate an island phase supporting effect, and the inherent mechanical property of the PBAT resin is reduced because the order of the PBAT resin is disturbed; in the proportioning test of the calcium carbonate powder and the PBAT resin, the two phenomena always exist and have a competitive action, the original mechanical strength of the PBAT material is improved when the calcium carbonate is added in an amount of 45-50 wt%, and the cost of raw materials is greatly reduced; 2. the organic silicon surface modifier is introduced into the sea-island structures of the continuous phase and the disperse phase, so that the compatibility of inorganic powder and PBAT is improved, and the ductility and the elongation at break of the modified material are improved compared with those of the original PBAT material, the transverse tensile strength of the material film product is 19.5MPa at most, the longitudinal tensile strength of the material film product is 22.3MPa at most, the transverse elongation at break of the material film product is 518% at most, and the longitudinal elongation at break of the material film product is 490% at most; 3. the negative pressure suction process is adopted to solve the problems of acidolysis and air bubbles of calcium carbonate in the mixed material at high temperature and the defects of the finished product of film blowing molding and injection molding; 4. the PBAT and calcium carbonate are blended and compounded, so that the problem of difficult PBAT degradation is solved, the biodegradability of the composite material is up to more than 90%, and the composite material can meet the industrial production requirements of environment-friendly degradable packaging bags, shopping bags, garbage bags and the like.

Drawings

FIG. 1 is a flow chart of the preparation of biodegradable environment-friendly materials;

FIG. 2 is a microstructure diagram of a biodegradable environment-friendly material;

FIG. 3 is an SEM image of the biodegradable environmental friendly material in example 1;

FIG. 4 is an SEM photograph of a material of experiment 2 without modification;

FIG. 5 is an SEM image of a material obtained by a conventional extrusion process in Experimental example 3;

FIG. 6 shows the change of the longitudinal tensile strength of the environmentally friendly material containing calcium carbonate inorganic powder in different addition amounts;

1-an inorganic powder; 2-modifying layer hydrophilic end; 3-modifying the hydrophobic end of the layer; 4-PBAT resin.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the scope of the present invention.

A biodegradable environment-friendly material is characterized in that the molecular structure of the biodegradable environment-friendly material is a reticular molecular structure with interpenetrating sea phases and island phases, biodegradable PBAT resin and inorganic powder modified by a surfactant are repeatedly linked, wound and kneaded to form a sea phase structure of the reticular molecular structure with interpenetrating sea phases and island phases, and the inorganic powder modified by the surfactant forms an island phase structure of the reticular molecular structure with interpenetrating sea phases and island phases; the surfactant layer connects the island phase and the sea phase;

the method comprises the following steps: 45 to 50 weight percent of inorganic powder, 45 to 55 weight percent of PBAT resin and 0.675 to 1.5 weight percent of surfactant.

Preferably, the inorganic powder is calcium carbonate, magnesium carbonate and calcium silicate; the grain size and the mesh number of the inorganic powder are more than 3000 meshes.

Preferably, the method further comprises the following steps: 0.225 to 0.5 weight percent of dispersant, 0.45 to 1 weight percent of lubricant, 0.225 to 0.5 weight percent of antioxidant and 0.225 to 0.5 weight percent of compatibilizer; the compatibilizer includes ADR.

Preferably, the surfactant comprises a silicone material.

Preferably, the organosilicon material comprises one or more of liquid hexamethyldisilazane, n-octadecyltrichlorosilane and hexadecyltrimethoxysilane.

Preferably, the transverse direction tensile strength of the material film product is 19.5MPa at most, the longitudinal direction tensile strength is 22.3MPa at most, the transverse direction breaking elongation is 518% at most, and the longitudinal direction breaking elongation is 490% at most.

A preparation method of a biodegradable environment-friendly material comprises the following steps:

conveying the inorganic powder into a heat-conducting oil heating type high-speed reaction kettle, taking a surfactant as a modifier, and repeatedly performing collision friction on the inorganic powder in a high-speed vortex form to perform reaction modification treatment on the inorganic powder to obtain second inorganic powder; providing the second inorganic powder with the surfactant-modified layer;

adding PBAT and the second inorganic powder into the high-speed reaction kettle, and performing linking winding to prepare a polymer I;

conveying the polymer I to a kneading machine, and carrying out eutectic kneading treatment to obtain a polymer II with a sea-island molecular structure; the kneading negative pressure is 100-1.01 multiplied by 10⁵Pa；

Conveying the polymer II to a surface mill hot cutting granulating chamber for granulation, cooling in an indirect water-cooling drum cooler, screening to obtain a final product, and carrying out vacuum packaging and storage on the final product;

and processing the first particles into a molded high polymer material.

And (3) rolling, blow molding or biaxial stretching the particles to prepare a film material, or extruding, blow molding or injection molding to prepare a plate or a container.

Preferably, the raw materials of the material comprise: 45 to 50 weight percent of inorganic powder, 45 to 55 weight percent of PBAT resin, 0.675 to 1.5 weight percent of surfactant, 0.225 to 0.5 weight percent of dispersant, 0.45 to 1 weight percent of lubricant and 0.225 to 0.5 weight percent of antioxidant.

Preferably, the modification treatment time is 15-20 min.

Preferably, the temperature of the link winding is 160-180 ℃; the link winding time is 30-40 min.

Preferably, the kneader comprises a double-strength paddle; the kneading rotating speed of the paddle is 100-120 r/min; the kneading time is 30-40 min; the kneading temperature is 150-180 ℃.

To verify the difference between the kneading process of the novel functional materials described herein and the conventional twin screw extrusion process, SEM analysis was performed on the materials made by both methods.

In order to verify the novel functional materials described herein, mechanical test equipment was introduced to test the tensile strength and elongation at break of the materials.

In order to verify the novel functional material, according to a compost degradation test GB T19277.1-2011, the specific method comprises the following steps:

(1) under simulated strongly aerobic composting conditions, the final aerobic biological decomposition capacity and the disintegration degree of the test material are measured; the inoculum used is derived from stable, rotten compost, if possible, obtained from compost of organic matter in municipal solid waste;

(2) mixing the test material with the inoculum, and introducing into a static compost container; in the vessel, the mixture is intensively aerobically composted at a prescribed temperature, oxygen concentration and humidity; the test period does not exceed 6 months;

(3) during the aerobic biological decomposition of the test material, carbon dioxide, water, mineralized inorganic salts and new biomass are the final biological decomposition products; continuously monitoring and periodically measuring the carbon dioxide generated by the test container and the blank container during the test, and accumulating the generated carbon dioxide;

(4) the ratio of the amount of carbon dioxide actually produced by the test material in the test to the theoretical amount of carbon dioxide that can be produced by the material is the percentage of biodegradation;

(5) the theoretical amount of carbon dioxide released can be calculated from the actual measured Total Organic Carbon (TOC) content, the percentage of biodegradation does not include the amount of carbon that has been converted to new cellular biomass, since it is not metabolized to carbon dioxide during the test period; the degree of disintegration of the test material can be determined at the end of the test, and the mass loss of the test material can also be measured.

In some alternative embodiments, the biodegradable plastic polybutylene terephthalate (PBAT) is used as a base material, and the calcium carbonate with 45-50% of surface modification is used as a filler to prepare the degradable high-filling composite material with better film blowing performance. The results of the measurement study, as shown in FIG. 6, indicate that the amount of calcium carbonate was adjusted and the same 0.5 wt% dispersant, 1 wt% lubricant, 0.5 wt% antioxidant, and 0.5 wt% compatibilizer was used, with the remainder being made up with PBAT; with the increase of the addition amount of calcium carbonate, the longitudinal tensile property of the calcium carbonate/PBAT composite material tends to decrease after being increased, because the low addition amount of calcium carbonate does not generate an island phase supporting effect, and the inherent mechanical property of the PBAT resin is reduced because the order of the PBAT resin is disturbed; during the proportioning test of the calcium carbonate powder and the PBAT resin, the two phenomena always exist and have a competitive action; thus, it is shown from FIG. 6 that only in the range of 5 to 55% by mass of calcium carbonate, the "island phase supporting effect" plays a dominant role; the tensile strength is much higher than pure PBAT resin. Furthermore, the use of the surface active modifier and the compatibilizer can obviously improve the tensile property of the calcium carbonate/PBAT (45-55 wt%) composite material, and the tensile property of the composite material reaches the best when the use amount of the surface active modifier and the compatibilizer is constant. As shown in fig. 3, when the film surface was observed by SEM, calcium carbonate was uniformly distributed and completely coated by PBAT. The composite material meets the mechanical property requirement of the market packaging material, greatly reduces the use cost of PBAT, has good application prospect, and greatly reduces the cost of raw materials.

In some optional embodiments, by adopting a unique kneading process, the adverse effect of degradation gas generation on the mechanical property of the material is removed, and the void ratio is reduced;

in some optional embodiments, by introducing the surfactant into the 'sea island' structures of the continuous phase and the disperse phase, the compatibility of the inorganic powder and the PBAT is improved, so that the modified material is greatly superior to the original ductility and elongation at break of the PBAT material, the biodegradation rate of a material system is improved, and the modified PBAT material has the functions of light, oxidation and biodegradation.

Example 1

On the basis of the disclosed embodiment, a biodegradable environment-friendly material is disclosed, wherein the molecular structure of the biodegradable environment-friendly material is a net-shaped molecular structure with interpenetrating sea phases and island phases, biodegradable PBAT resin and inorganic powder modified by a surfactant are repeatedly linked, wound and kneaded to form a sea phase structure with an interpenetrating net-shaped molecular structure with the sea phases and the island phases, and the inorganic powder modified by the surfactant forms an island phase structure with an interpenetrating net-shaped molecular structure with the sea phases and the island phases; the surfactant layer connects the island phase and the sea phase;

the method comprises the following steps: 48 wt% of inorganic powder, 50 wt% of PBAT resin and 1 wt% of surfactant.

Preferably, the inorganic powder is calcium carbonate; the grain size and the mesh number of the inorganic powder are more than 3000 meshes.

Preferably, the method further comprises the following steps: 0.5 wt% of dispersant, 1 wt% of lubricant, 0.5 wt% of antioxidant and 0.5 wt% of compatibilizer; the compatibilizer is ADR.

Preferably, the surfactant comprises a silicone material.

Preferably, the organosilicon material is KH 560.

conveying the polymer I to a kneading machine, and carrying out eutectic kneading treatment to obtain a polymer II with a sea-island molecular structure; the kneading negative pressure is 100 Pa;

and (3) rolling, blow molding or biaxial stretching the first particle to prepare a film material.

Preferably, the raw materials of the material comprise: 48 wt% of inorganic powder, 50 wt% of PBAT resin, 1 wt% of surfactant, 0.5 wt% of dispersant, 1 wt% of lubricant, 0.5 wt% of antioxidant and 0.5 wt% of compatibilizer; the compatibilizer is ADR.

Preferably, the surfactant comprises a silicone material.

Preferably, the organosilicon material is KH 560.

Preferably, the modification treatment time is 20 min.

Preferably, the temperature of the chain winding is 180 ℃; the link winding time was 40 min.

Preferably, the kneader comprises a double-strength paddle; the kneading speed of the paddle is 120 r/min; the time required for kneading is 40 min; the kneading temperature was 180 ℃.

The embodiment also discloses a biodegradable environment-friendly material, which is prepared according to the method, as shown in fig. 2, the PBAT resin and the inorganic powder modified by in-situ polymerization are repeatedly linked, wound and kneaded to form a mesh molecular structure with interpenetrating sea and island phases, the sea phase is a PBAT biodegradable high molecular material (4 shown in fig. 2), the island phase is an inorganic powder (1 shown in fig. 2), and a surfactant hydrophilic layer (2 shown in fig. 2) and a surfactant hydrophobic layer (3 shown in fig. 2) are sequentially distributed around the island phase from inside to outside.

Research results show that with the increase of the addition amount of calcium carbonate, the longitudinal tensile property of the calcium carbonate/PBAT composite material tends to be reduced after being reduced, and the use of the surface active modifier KH560 and the compatibilizer ADR can obviously improve the tensile property of the calcium carbonate/PBAT (45-50 wt%) composite material, and when the use amount of the surface active modifier KH560 and the compatibilizer is 0.5 wt%, the tensile property of the composite material is optimal, the transverse tensile strength of the PBAT (50 wt%) film product can reach 19.5MPa, the longitudinal tensile strength can reach 22.3MPa, the transverse elongation at break is 518%, the longitudinal elongation at break is 490%, and the melt index is 1.58g/10 min. As shown in fig. 3, when the film surface was observed by SEM, calcium carbonate was uniformly distributed, completely coated by PBAT impregnation, and no bubbles were observed. The composite material meets the mechanical property requirement of the market packaging material, greatly reduces the use cost of PBAT and has good application prospect.

Example 2

the method comprises the following steps: 43 wt% of inorganic powder, 55 wt% of PBAT resin and 0.8 wt% of surfactant.

Preferably, the inorganic powder is magnesium carbonate; the grain size and the mesh number of the inorganic powder are more than 3000 meshes.

Preferably, the method further comprises the following steps: 0.45 wt% of dispersant, 0.8 wt% of lubricant, 0.45 wt% of antioxidant and 0.45 wt% of compatibilizer; the compatibilizer is ADR.

Preferably, the surfactant comprises a silicone material.

Preferably, the organosilicon material is KH 550.

The transverse tensile strength of the material film product is 18.5MPa, the longitudinal tensile strength is 21.3MPa at most, the transverse elongation at break is 508 percent at most, and the longitudinal elongation at break is 476 percent at most.

conveying the polymer I to a kneading machine, and carrying out eutectic kneading treatment to obtain a polymer II with a sea-island molecular structure; the kneading negative pressure is 1.00 multiplied by 10⁵Pa；

Preferably, the surfactant comprises a silicone material.

Preferably, the organosilicon material is KH 550.

Preferably, the modification treatment time is 15 min.

Preferably, the temperature of the chain winding is 160 ℃; the link winding time was 30 min.

Preferably, the kneader comprises a double-strength paddle; the kneading speed of the paddle is 100 r/min; the kneading time is 30 min; the kneading temperature was 150 ℃.

The embodiment also discloses a biodegradable environment-friendly material, which is prepared according to the method, as shown in fig. 2, the PBAT resin and the inorganic powder modified by in-situ polymerization are repeatedly linked, wound and kneaded to form a mesh molecular structure with interpenetrating sea and island phases, the sea phase is a PBAT biodegradable high molecular material (4 shown in fig. 2), the island phase is an inorganic powder (1 shown in fig. 2), and a surfactant hydrophilic layer (2 shown in fig. 2) and a surfactant hydrophobic layer (34 shown in fig. 2) are sequentially distributed around the island phase from inside to outside.

In some alternative embodiments, the biodegradable plastic polybutylene terephthalate (PBAT) is used as a base material, and the calcium carbonate with 45-50% of surface modification is used as a filler to prepare the degradable high-filling composite material with better film blowing performance. Research results show that with the increase of the addition amount of calcium carbonate, the longitudinal tensile property of the calcium carbonate/PBAT composite material tends to decrease after being increased, while the use of the surface active modifier and the compatibilizer can obviously improve the tensile property of the calcium carbonate/PBAT (45-50 wt%) composite material, and when the use amounts of the surface active modifier and the compatibilizer are fixed, the tensile property of the composite material reaches the best. As shown in FIG. 3, when the film surface was observed by SEM, calcium carbonate was uniformly distributed and bubble-free, and was completely coated by PBAT infiltration. The composite material meets the mechanical property requirement of the market packaging material, greatly reduces the use cost of PBAT, has good application prospect, and greatly reduces the cost of raw materials.

Example 3

The embodiment discloses a preparation method of a biodegradable environment-friendly material, and as shown in fig. 1, the biodegradable environment-friendly material has a molecular structure of a reticular molecular structure with interpenetrating sea phases and island phases, wherein a biodegradable PBAT resin and inorganic powder modified by a surfactant are repeatedly linked, wound and kneaded to form a sea phase structure of the reticular molecular structure with interpenetrating sea phases and island phases, and the inorganic powder modified by the surfactant forms an island phase structure of the reticular molecular structure with interpenetrating sea phases and island phases; the surfactant layer connects the island phase and the sea phase;

the method comprises the following steps: 45 wt% of inorganic powder, 45 wt% of PBAT resin and 0.675 wt% of surfactant.

Preferably, the inorganic powder is calcium silicate; the grain size and the mesh number of the inorganic powder are more than 3000 meshes.

Preferably, the method further comprises the following steps: 0.225 wt% of dispersant, 0.45 wt% of lubricant, 0.225 wt% of antioxidant and 0.225 wt% of compatibilizer; the compatibilizer includes ADR.

Preferably, the surfactant comprises a silicone material.

Preferably, the organosilicon material is liquid hexamethyldisilazane.

Preferably, the material plate product has a tensile strength of at most 23.3MPa and an elongation at break of at most 435%.

conveying the polymer I to a kneading machine, and carrying out eutectic kneading treatment to obtain a polymer II with a sea-island molecular structure; the kneading negative pressure is 5.0 multiplied by 10⁴Pa；

and (3) extruding and injection molding the particles to prepare a plate material.

Preferably, the raw materials of the material comprise: 45 wt% of inorganic powder, 50 wt% of PBAT resin, 0.675 wt% of surfactant, 0.225 wt% of dispersant, 0.45 wt% of lubricant and 0.225 wt% of antioxidant.

Preferably, the modification treatment time is 15 min.

Preferably, the temperature of the chain winding is 170 ℃; the link winding time was 35 min.

Preferably, the kneader comprises a double-strength paddle; the kneading speed of the paddle is 110 r/min; the time required for kneading is 35 min; the kneading temperature was 170 ℃.

In some alternative embodiments, biodegradable plastic polybutylene terephthalate (PBAT) is used as a base material, and 45-50 wt% of surface modified calcium carbonate is used as a filler to prepare the degradable high-filling composite material with better film blowing performance. Research results show that with the increase of the addition amount of calcium carbonate, the longitudinal tensile property of the calcium carbonate/PBAT composite material tends to decrease after being increased, while the use of the surface active modifier and the compatibilizer can obviously improve the tensile property of the calcium carbonate/PBAT (45-50 wt%) composite material, and when the use amounts of the surface active modifier and the compatibilizer are fixed, the tensile property of the composite material reaches the best.

Experimental example 1

In order to better verify the biodegradable environment-friendly material, the PBAT material without inorganic powder, the processing method and other raw materials are the same as those in example 1.

Experimental example 2

In order to better verify the biodegradable environment-friendly material, the inorganic powder modified material without adding a surfactant, the processing method and other raw materials are the same as those in example 1.

Experimental example 3

In order to better verify the influence of the existing kneading process on the performance of the membrane material, an experimental example 2 was set up, wherein CN 111944280A, a PBAT composite material containing modified wollastonite and the preparation method thereof are adopted, and a multifunctional degradable material is prepared by double screws in the method disclosed by the preparation method, and the formula is the same as that in example 1.

SEM tests of example 1 and experimental examples 1-3 are carried out, and the test results are shown in figures 3 to 5, the SEM picture of example 1 is uniform and bubble-free, and the island phase calcium carbonate powder, the sea phase PBAT resin and the active agent modification layer can be clearly distinguished; experimental example 2 can distinguish island phase calcium carbonate powder and sea phase PBAT resin; experimental example 3 had more bubbles, resulting from the decomposition of PBAT and calcium carbonate.

The results of mechanical tests on the embodiment 1 and the experimental examples 1-3 are shown in the following table, the tensile strength and the elongation at break of the embodiment 1 are greatly improved compared with those of the experimental example 1 without adding the filler and the experimental example 2 without modifying the filler, the problem of difficulty in processing the PBAT film is solved, the performance close to that of a PE film material is obtained, and the practical value is important; the embodiment 1 solves the problems of film material degradation and void ratio in the prior art, and obviously improves the mechanical property compared with the experimental example 3.

Experimental project	Example 1	Experimental example 1	Experimental example 2	Experimental example 3
					Transverse tensile strength/MPa	19.5	15.2	13.4	8.2
Transverse elongation at break/%)	518	440	282	245
					Longitudinal tensile strength/MPa	22.3	17.2	19.2	14.1
Longitudinal elongation at break/%)	490	462	312	180

Compost degradation experiments were performed for example 1 and experimental examples 1-3, with the results shown in the following table:

example 1 the degradation speed is obviously faster than that of the prior art, namely, experiment example 3 in which modified wollastonite is added and experiment example 1 in which calcium carbonate inorganic powder is not added, which shows that the modified calcium carbonate can promote the degradation of PBAT and the degradation rate is better than that of the modified wollastonite.

Residual mass/%)	Example 1	Experimental example 1	Experimental example 2	Experimental example 3
					30d	52	83	63	89
60d	4.4	41	31	58
					120d	0.5	2.3	9	33
180d	0.52	0.11	0.51	5

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in practice.

Claims

1. A biodegradable environment-friendly material is characterized by comprising: 45 wt% -50 wt% of inorganic powder, 45 wt% -55 wt% of PBAT resin and 0.675 wt% -1.5 wt% of surfactant; the biodegradable environment-friendly material has a reticular molecular structure with two interpenetrating phases of a sea phase structure and an island phase structure; the modified inorganic powder is obtained by modifying the inorganic powder through the surfactant, the island phase structure is composed of the modified inorganic powder, and the reticular molecular structure is formed by repeatedly linking, winding and kneading the modified inorganic powder and the PBAT resin.

2. The biodegradable environmentally friendly material according to claim 1, wherein the inorganic powder comprises calcium carbonate, magnesium carbonate and calcium silicate; the particle size of the inorganic powder is more than 3000 meshes.

3. The biodegradable environmentally friendly material of claim 1, further comprising: 0.225 to 0.5 weight percent of dispersant, 0.45 to 1 weight percent of lubricant, 0.225 to 0.5 weight percent of antioxidant and 0.225 to 0.5 weight percent of compatibilizer.

4. The biodegradable, environmentally friendly material of claim 3, wherein the compatibilizer comprises ADR.

5. The biodegradable, environmentally friendly material of claim 1, wherein the surfactant comprises a silicone material.

6. The biodegradable environmentally friendly material of claim 5, wherein the organosilicon material comprises at least one of liquid hexamethyldisilazane, n-octadecyltrichlorosilane, and hexadecyltrimethoxysilane.

7. The preparation method of the biodegradable environment-friendly material is characterized by comprising the following steps of:

8. The method for preparing biodegradable environment-friendly material according to claim 7, characterized in that the modification treatment time in step 1 is 15min to 20 min; the temperature of the chain connection winding in the step 2 is 160-180 ℃, and the time is 30-40 min; in the step 3, the kneading speed of the paddle is 100r/min-120r/min, the kneading time is 30min-40min, and the kneading temperature is 150-180 ℃; the negative pressure in the step 3 is 100-1.01X 105 Pa.

9. Use of a biodegradable environmental friendly material, characterized in that the biodegradable environmental friendly material according to any one of claims 1 to 6 or the biodegradable environmental friendly material prepared by the method according to any one of claims 7 to 8 is subjected to calendering, blow molding or biaxial stretching to form a material film product; or the biodegradable environment-friendly material is extruded, blow-molded or injection-molded to form a material plate or a container.

10. The use according to claim 9, wherein the material film product has a transverse tensile strength of 19.5MPa or more, a longitudinal tensile strength of 22.3MPa or more, a transverse elongation at break of 518% or more, and a longitudinal elongation at break of 490% or more.