CN108752940A - A kind of preparation method of degradable garbage bags - Google Patents

Abstract

The invention discloses a preparation method of a degradable garbage bag, which is prepared from the following raw materials in parts by weight: 40-70 parts of defatted soybean meal, 40-70 parts of polylactic acid, 10-15 parts of glycerin, and 1-3 parts of environmentally friendly pigments 10-15 parts of water, 10-50 parts of talcum powder. The garbage bag produced by the treatment process of the present invention has the advantages of non-toxicity, environmental protection, no pollution, light weight, high tensile strength, high right-angle tear strength, low water absorption, high elongation at break, biodegradability, and no need for recycling. features.

Description

A kind of preparation method of degradable garbage bags

Technical field

The invention belongs to refuse bag fields, and in particular to a kind of preparation method of degradable garbage bags.

Background technology

The polybag of people's daily shopping be mostly with made of oil, due to the use of enormous amount, caused by resource Waste, environmental pollution are very surprising.Polybag is embedded in underground and wanted about 200 years and could rot, and serious contaminated soil；Such as Fruit takes burning disposal mode, then will produce noxious fume and toxic gas, long-term pollution environment.

Chinese 1,000,000,000 polybags that use up of buying vegetables daily, the dosage of other various polybags is daily at 2,000,000,000 or more. 2,300,000,000 polybags are discarded in Beijing every year, are generated 140,000 tons of waste plastic packaging waste, are accounted for the 3% of entire house refuse.Shanghai is every Year generates 190,000 tons of waste plastic packaging waste, accounts for the 7% of house refuse total amount.The annual waste plastic packaging waste in Tianjin More than 100,000 tons.The polybag that market is given all is mainly nondegradable, if being used as refuse bag, will seriously endanger environment.

Invention content

The purpose of the present invention is for existing problem, provide a kind of preparation method of degradable garbage bags.

The invention is realized by the following technical scheme：

A kind of degradable garbage bags are made of the raw material of following parts by weight：40~70 parts of de-fatted soybean dregs, polylactic acid 40~70 Part, 10 ~ 15 parts of glycerine, 1~3 part of environmental-friendly pigment, 10~15 parts of water, 10~50 parts of talcum powder.

A kind of preparation method of degradable garbage bags, includes the following steps：(1) respectively by de-fatted soybean dregs and clear water by material Liquid mass ratio 1：8 mixing adjust pH value to progress first time extraction, extraction under the conditions of 7.5,45 DEG C with 0.5mol/L NaOH After 10min, double gauze filtering retains filtrate, and levigator mill excessively is even after filter residue adds 2 times of deionized waters to stir evenly, levigate Afterwards again plus 3 times of deionized waters, pH value is adjusted to 7.5 with the NaOH of 0.5mol/L, carry out second under room temperature and extract, extraction After 30min, double gauze filtering will filter gained filtrate mixing twice, and high speed centrifugation 3min removes residue, with 1moL/L's Low-speed centrifugal 3min after HCl adjusting supernatant pH values sink to 4.4,40 DEG C of acid, the gained precipitation broken rear plus 4 times of clear water of blender solution, PH value to neutrality is adjusted with the NaOH of 1mol/L to redissolve, and with acetic anhydride acetylation, is slowly added into acid while stirring at room temperature Acid anhydride, and it is interior constant with the NaOH solution adjusting PH of 0.1~0.3mol/L during this period, and sustained response l~2 hour are straight To after the reaction was complete (mixture pH value is stablized constant), PH values are adjusted to pH value to 4.5 with hydrochloric acid, are then centrifuged for isolating Acylated protein, then after washing, adjusting PH to neutrality acetylated soybean albumen is obtained after drying；(2) silane coupling agent surface is used Processing, the acetylated soybean albumen after being coupled after dry；(3) by the acetylated soybean albumen after coupling, glycerine, environmental protection Pigment, water, talcum powder stir in blender, stand 30min to balancing each other, by mixture and polylactic acid and increase-volume Agent is blended 3~5min in mixer, and temperature is 160 DEG C, and blend melt is quenched to room temperature and crushing and granulates, and obtains particle Material；(4) particulate material is put into extruder, material is melted in barrel by the effect of temperature and shearing force, and by screw rod Push head to, takes double bubble expressing techniques, be first quenched the melt squeezed out from co-extrusion die head with cold water, film is made in cooling stretch Pipe；(5) by membrane tube reheating, inflation, cooling, stretching, through cooling and shaping, tension force, thickness measuring, sided corona treatment, deburring point Cut, winding to get.Further, the bulking agent in (3) step is existed for 3/7 soya-bean polypeptides and lactide by mass ratio At 100 DEG C, vacuum is sufficiently stirred reaction and block copolymer is made under stannous octoate and dibutyltindilaurate catalyzed system.

Further, extrusion temperature is in (4) step：First segment, 140~150 DEG C；Second segment, 150~160 DEG C；Third Section, 160~170 DEG C；Latter end, 170~175 DEG C.

Beneficial effects of the present invention：

In a kind of preparation process of degradable garbage bags provided by the invention, two kinds of rings of polylactic acid and soybean protein are mainly applied Protect recyclable materials.Polylactic acid is with lactic acid for the obtained high molecular polymer of main polymerizable raw material, easily natural decomposition, than Weight is relatively low, has fabulous feel, drapability and appearance, good resilience, excellent curling and crimp retention to have controllable receipts Contracting, intensity are high, are not easy by influence of ultraviolet light, can use a variety of dyeings, outstanding machinability, and bonding temperature is controllable System, crystalline melt temperatures are up to 120 DEG C -230 DEG C, low combustible.It can be by microorganism（Such as bacterium, fungi and algae）Completely Decompose the material for becoming low molecular compound.But the refuse bag of single polylactic acid component is difficult to control its degradation progress and time, Cause polylactic acid refuse bag poor using durability degree, the time is short.Soybean protein acid resistance corrosive nature is excellent, and dyefastness is high, ruler Very little stability is good, easy cleaning, quick-drying.However make its processing containing hydrophilic radicals such as a large amount of amino, carboxyls in soybean protein molecule Difficulty, poor water resistance easily absorb water and lead to performance degradation, the development of soybean protein material is made to be restricted.And pass through Surface treatment, the hydrophilic interaction on reduction soybean protein surface, and by adjusting soybean protein ratio in formula, reach refuse bag The biodegradable effect soybean protein of controllable time has stronger anti-microbial property, to bacteriums such as Escherichia coli, Candida albicans There is inhibiting effect, is conducive to the parasitism for preventing bacterium.Acetylation can improve its water proofing property with the side chain of modified soy protein Energy.Material can be improved in water toughness and processability is added, a small amount of talcum powder, which is added, can increase water proofing property.And soybean egg Just there is good ageing resistance so there is no need to add additional synthesis antioxidant containing natural antioxidant content isoflavones in white Can, into the pollution without causing antioxidant ingredient.

The present invention has the following advantages compared with prior art：

A kind of preparation method of degradable garbage bags provided by the invention gathers breast using two kinds of sustainable regrown materiaves of environmental protection Acid and soybean protein give full play to the special performance of two kinds of materials by specially treated.The microbial action existing for nature It can cause to degrade, and final degradable become carbon dioxide (CO₂) or/and methane (CH₄), water (H₂) and its contained element O Mineralising inorganic salts, degradation process environmental protection, environmental pollution will not be caused, can effectively solve the rings such as the pollution that disposed waste bag is brought Border problem.A small amount of degradable garbage bags product is only deposited currently on the market, comprehensive performance is bad, and of high cost, it is difficult to which volume production obtains Less than practical application.And most of is half degradation products, i.e. biological disintegration material.Its main body is still synthesis tree difficult to degrade Fat does not solve the problems, such as inherently.Moreover, by the oxidation resistance of soybean protein itself isoflavones, artificial conjunction is not added At antioxidant, reduce cost, avoid pollution.

Specific implementation mode

Illustrate the present invention with specific embodiment below, but is not limitation of the present invention.

Embodiment 1

A kind of degradable garbage bags are made of the raw material of following parts by weight：40 parts of de-fatted soybean dregs, 40 parts of polylactic acid, glycerine 10 Part, 2 parts of environmental-friendly pigment, 10 parts of water, 50 parts of talcum powder.

A kind of preparation method of degradable garbage bags, includes the following steps：(1) respectively by de-fatted soybean dregs and clear water by material Liquid mass ratio 1：8 mixing adjust pH value to progress first time extraction, extraction under the conditions of 7.5,45 DEG C with 0.5mol/L NaOH After 10min, double gauze filtering retains filtrate, and levigator mill excessively is even after filter residue adds 2 times of deionized waters to stir evenly, levigate Afterwards again plus 3 times of deionized waters, pH value is adjusted to 7.5 with the NaOH of 0.5mol/L, carry out second under room temperature and extract, extraction After 30min, double gauze filtering will filter gained filtrate mixing twice, and high speed centrifugation 3min removes residue, with 1moL/L's Low-speed centrifugal 3min after HCl adjusting supernatant pH values sink to 4.4,40 DEG C of acid, the gained precipitation broken rear plus 4 times of clear water of blender solution, PH value to neutrality is adjusted with the NaOH of 1mol/L to redissolve, and with acetic anhydride acetylation, is slowly added into acid anhydrides while stirring at room temperature, And during this period in the NaOH solution of 0.2mol/L to adjust PH constant, sustained response 1 hour is until the reaction is complete After (mixture pH value is stablized constant), PH values are adjusted to pH value to 4.5 with hydrochloric acid, are then centrifuged for isolating acylated protein, then After washing, adjusting PH to neutrality acetylated soybean albumen is obtained after drying；(2) it is surface-treated with silane coupling agent, after dry Acetylated soybean albumen after being coupled；(3) by acetylated soybean albumen, glycerine, environmental-friendly pigment, water, the talcum after coupling Powder stirs in blender, stands 30min to balancing each other, by mixture and polylactic acid and bulking agent in mixer Be blended 4min, temperature be 160 DEG C, blend melt be quenched to room temperature and crush granulate, obtain particulate material；4) particulate material is put into In extruder, material is melted in barrel by the effect of temperature and shearing force, and pushes head to by screw rod, and double bubbles is taken to squeeze Go out technique, be first quenched the melt squeezed out from co-extrusion die head with cold water, membrane tube is made in cooling stretch；(5) by membrane tube reheating, Inflation, cooling, stretching, through cooling and shaping, tension force, thickness measuring, sided corona treatment, deburring cut, winding to get.

Further, the bulking agent in (3) step be by mass ratio be 3/7 soya-bean polypeptides and lactide at 100 DEG C Under, vacuum is sufficiently stirred reaction and block copolymer is made under stannous octoate and dibutyltindilaurate catalyzed system.

Further, extrusion temperature is in (4) step：First segment, 145 DEG C；Second segment, 155 DEG C；Third section, 165 DEG C； Latter end, 170 DEG C.

Embodiment 2

A kind of degradable garbage bags are made of the raw material of following parts by weight：30 parts of de-fatted soybean dregs, 50 parts of polylactic acid, glycerine 10 Part, 2 parts of environmental-friendly pigment, 10 parts of water, 50 parts of talcum powder.

A kind of preparation method of degradable garbage bags, includes the following steps：(1) respectively by de-fatted soybean dregs and clear water by material Liquid mass ratio 1：8 mixing adjust pH value to progress first time extraction, extraction under the conditions of 7.5,45 DEG C with 0.5mol/L NaOH After 10min, double gauze filtering retains filtrate, and levigator mill excessively is even after filter residue adds 2 times of deionized waters to stir evenly, levigate Afterwards again plus 3 times of deionized waters, pH value is adjusted to 7.5 with the NaOH of 0.5mol/L, carry out second under room temperature and extract, extraction After 30min, double gauze filtering will filter gained filtrate mixing twice, and high speed centrifugation 3min removes residue, with 1mol/L's Low-speed centrifugal 3min after HCl adjusting supernatant pH values sink to 4.4,40 DEG C of acid, the gained precipitation broken rear plus 4 times of clear water of blender solution, PH value to neutrality is adjusted with the NaOH of 1mol to redissolve, and with acetic anhydride acetylation, is slowly added into acid anhydrides while stirring at room temperature, And during this period in the NaOH solution of 0.2mol/L to adjust PH constant, sustained response 1 hour is until the reaction is complete After (mixture pH value is stablized constant), PH values are adjusted to pH value to 4.5 with hydrochloric acid, are then centrifuged for isolating acylated protein, then After washing, adjusting PH to neutrality acetylated soybean albumen is obtained after drying；(2) it is surface-treated with silane coupling agent, is obtained after dry Acetylated soybean albumen after to coupling；(3) by acetylated soybean albumen, glycerine, environmental-friendly pigment, water, the talcum powder after coupling It is stirred in blender, stands 30min to balancing each other, in mixer altogether by mixture and polylactic acid and bulking agent Mixed 4min, temperature are 160 DEG C, and blend melt is quenched to room temperature and crushing and granulates, and obtains particulate material；(4) particulate material is put into In extruder, material is melted in barrel by the effect of temperature and shearing force, and pushes head to by screw rod, and double bubbles is taken to squeeze Go out technique, be first quenched the melt squeezed out from co-extrusion die head with cold water, membrane tube is made in cooling stretch；(5) by membrane tube reheating, Inflation, cooling, stretching, through cooling and shaping, tension force, thickness measuring, sided corona treatment, deburring cut, winding to get.

Further, the bulking agent in (3) step be by mass ratio be 3/7 soya-bean polypeptides and lactide at 100 DEG C Under, vacuum is sufficiently stirred reaction and block copolymer is made under stannous octoate and dibutyltindilaurate catalyzed system.

Further, extrusion temperature is in (4) step：First segment, 145 DEG C；Second segment, 155 DEG C；Third section, 165 DEG C； Latter end, 170 DEG C.

Comparative example 1

This comparative example compared with Example 2, in raw material weighs step, saves de-fatted soybean dregs ingredient, method step in addition to this Rapid all same.

Comparative example 2

This comparative example compared with Example 2, in raw material weighs step, saves compatilizer ingredient, method and step in addition to this is equal It is identical.

Comparative example 3

This comparative example compared with Example 2, in raw material weighs step, saves polylactic acid ingredient, method and step in addition to this is equal It is identical.

The mechanical property of refuse bag prepared by 1 each embodiment and comparative example of table

Note：It is tested with reference to GB/T 28018-2011；Compost Biodegradation is tested：By above-mentioned obtained each group refuse bag according to GB/T 19277.2-2013 carry out compost degradation experiment, want strict temperature control, moisture in experimentation, and test period is 50 days.Tension rope drawing force, the biodegradability of refuse bag made from treatment process of the present invention it can be seen from upper table 1 obtain Effective improvement is arrived, while the control of its anti-permeability performance, drop performance is preferable, it can be very nearly the same with originality.Present invention processing Refuse bag made from technique have nontoxic, environmentally friendly, pollution-free, light-weight, tensile strength is big, angle tear strength is big, can biology drop It solves, without the good characteristics of recycling.

Claims (4)

1. a preparation method of degradable garbage bag, is characterized in that, is made of the raw material of following parts by weight: 40-70 parts of defatted soybean meal, 40-70 parts of polylactic acid, 10-15 parts of glycerin, 1-3 parts of environmental pigments, 10-15 parts of water, 10-50 parts of talcum powder. 2. The preparation method of a kind of degradable garbage bag according to claim 1, characterized in that it comprises the following steps: (1) respectively mixing defatted soybean meal and clear water according to the mass ratio of material to liquid at 1:8, and using 0.5mol /L NaOH to adjust the pH value to 7.5, and carry out the first extraction at 45°C. After extraction for 10 minutes, filter with double-layer gauze and keep the filtrate, and add 2 times deionized water to the filter residue, stir evenly, and then pass it through a water mill to grind evenly. Then add 3 times more deionized water, adjust the pH value to 7.5 with 0.5mol/L NaOH, and conduct the second extraction at room temperature. After extraction for 30 minutes, filter with double-layer gauze, mix the filtrate obtained from the two filtrations, and centrifuge at high speed for 3 minutes , remove the residue, adjust the pH value of the supernatant to 4.4 with 1mol/L HCl, centrifuge at a low speed for 3 minutes after acid precipitation at 40°C, disintegrate the obtained precipitate with a mixer, add 4 times of water, and adjust the pH value to medium with 1mol/L NaOH Redissolve with acetic anhydride, acetylate with acetic anhydride, add acid anhydride slowly while stirring at room temperature, and use 0.1-0.3mol/L NaOH solution to adjust the pH during this period, and continue to react for 1-2 hours until the reaction is complete (mixture After the pH value is stable), adjust the pH value to 4.5 with hydrochloric acid, then centrifuge to separate the acylated protein, then wash with water, adjust the pH to neutral, and then dry to obtain acetylated soybean protein; (2) use silane Coupling agent surface treatment, drying to obtain coupled acetylated soybean protein; (3) fully stir the coupled acetylated soybean protein, glycerin, water, and talcum powder in a mixer, and let stand for 30 minutes until phase equilibrium , blend the mixture with polylactic acid and compatibilizer in an internal mixer for 3 to 5 minutes at a temperature of 160°C, quench the blend melt to room temperature and crush it into granules to obtain granules; (4) put the granules into In the extruder, the material is melted under the action of temperature and shear force in the barrel, and pushed to the machine head by the screw. The double-bubble extrusion process is adopted. First, the melt extruded from the co-extrusion die is quenched with cold water. Cold, cooling and stretching to make the film tube; (5) secondary heating, inflation, cooling and stretching of the film tube, cooling and shaping, tension control, thickness measurement, corona treatment, trimming and cutting, winding, Instantly. 3. the preparation method of a kind of degradable garbage bag according to claim 2, is characterized in that: the compatibilizer of described step (3) is that soybean polypeptide and lactide are 3/7 by mass ratio at 100 At ℃, under the catalytic system of stannous octoate and dibutyltin dilaurate, the block copolymer was prepared by fully stirring and reacting under vacuum. 4. The preparation method of a degradable garbage bag according to claim 2, characterized in that: the extrusion temperature in the step (4) is: first section, 140-150°C; second section, 150-150°C 160°C; the third stage, 160~170°C; the last stage, 170~175°C.