阅读说明：本技术 一种全降解无氟纸浆模塑育苗杯及其制备方法 (Full-degradable fluoride-free paper pulp molding seedling cup and preparation method thereof ) 是由 王建华 陈华 管正光 陈波 何永梁 丁锦晖 杨凡 毛长斌 于 2020-05-18 设计创作，主要内容包括：本发明公开了一种全降解无氟纸浆模塑育苗杯的生产方法,将纸浆原料配比后疏解得均匀的浆料,加入防水剂、湿强剂、干强剂等助剂制得混合浆料；将聚甲基丙烯酸甲酯-丙烯酸乙酯聚合物溶于甲苯溶液,搅拌后加入二氧化硅纳米颗粒,搅拌后加入乙醇溶液,然后在湿胚上进行喷涂；最后将纸浆模塑湿坯进行脱水、热压定型、切边制成模塑制品。本发明提供的全降解无氟纸浆模塑育苗杯为绿色环保全降解材料,其废弃后可直接丢弃并自然降解成种植用土壤；或经破碎还原成种植用土壤进行复用或丢弃。(The invention discloses a method for producing a fully-degradable fluoride-free paper pulp molded seedling cup, which comprises the steps of proportioning paper pulp raw materials, defibering to obtain uniform slurry, and adding assistants such as a waterproof agent, a wet strength agent, a dry strength agent and the like to prepare mixed slurry; dissolving polymethyl methacrylate-ethyl acrylate polymer in a toluene solution, adding silicon dioxide nano particles after stirring, adding an ethanol solution after stirring, and then spraying on a wet blank; finally, dehydrating, hot-pressing and shaping the pulp molding wet blank, and cutting edges to obtain a molding product. The fully-degradable fluoride-free paper pulp molding seedling cup provided by the invention is a green environment-friendly fully-degradable material, can be directly discarded after being discarded and can be naturally degraded into soil for planting; or the soil is crushed and reduced into planting soil for reuse or discarded.)

1. A preparation method of a full-degradable fluoride-free paper pulp molding seedling raising cup comprises the following steps:

step 1: the paper pulp raw materials are measured according to the proportion, a hydraulic pulper is used for pulping to obtain pulp, and the mass concentration of the pulp is 3.5% -4.0% during pulping;

step 2: defibering the treated pulp by using a dual-function defibering machine, and cutting, splitting and attenuating fibers by using the defibering machine to obtain uniform pulp;

and step 3: mixing the pulp with white water, adding chemical medicines such as a waterproof agent, a wet strength agent, a dry strength agent and the like, and uniformly stirring to prepare mixed pulp;

and 4, step 4: conveying the mixed slurry to a forming machine through a pipeline, and performing vacuum filtration and dehydration to obtain a wet embryo of the seedling cup;

and 5: spraying wet embryos of the seedling cup: adding silicon dioxide nanoparticles into a polymethyl methacrylate-ethyl acrylate polymer solution at 40-50 ℃, stirring for 10-20 minutes, then adding an ethanol solution, uniformly stirring, and spraying on the surface of a wet embryo of a seedling cup;

step 6: and (3) dehydrating, hot-pressing for shaping, transferring and trimming the sprayed wet blank of the seedling cup to obtain a finished product of the fully-degradable fluorine-free paper pulp molded seedling cup.

2. The method for preparing the full-degradable fluoride-free pulp molding nursery cup as claimed in claim 1, wherein the method comprises the following steps: in the step 1, the paper pulp raw materials are sugarcane pulp and bamboo pulp, and the ratio of the raw materials to the raw materials is 30-40: 60-70 wt%.

3. The method for preparing the full-degradable fluoride-free pulp molding nursery cup as claimed in claim 1, wherein the method comprises the following steps: in step 2, the properties of the obtained slurry: the wet weight is 14-17 g, the beating degree is 20-23 DEG SR, and the viscosity is 60-70 Pa.s.

4. The method for preparing the full-degradable fluoride-free pulp molding nursery cup as claimed in claim 1, wherein the method comprises the following steps: in the step 3, the pulp and the white water are mixed and mixed according to the setting of a DCS control system, the concentration of the mixed pulp is 0.27-0.32%, and the pulp mixing time is 15-25 min.

5. The method for preparing the full-degradable fluoride-free pulp molding nursery cup as claimed in claim 1, wherein the method comprises the following steps: in the step 3, the waterproof agent does not contain fluororesin, the wet strength agent is polyamide polyepichlorohydrin resin, and the dry strength agent is starch and a modified substance thereof.

6. The method for preparing the full-degradable fluoride-free pulp molding nursery cup as claimed in claim 1, wherein the method comprises the following steps: the operation parameters of the dehydration treatment of the pulp molding wet blank in the step 4 are as follows: and (3) dehydrating for 15-20 s under the suction negative pressure of-0.03 MPa to-0.035 MPa until the water content is 65-75%.

7. The method for preparing the full-degradable fluoride-free pulp molding nursery cup as claimed in claim 1, wherein the method comprises the following steps: the particle size of the silicon dioxide nano particles used in the step 5 is 15-25 nm.

8. The method for preparing the full-degradable fluoride-free pulp molding nursery cup as claimed in claim 1, wherein the method comprises the following steps: the spraying amount in the step 5 process is as follows: the weight of the pulp absolutely dry fiber is 1-5%.

9. The method for preparing the full-degradable fluoride-free pulp molding seedling raising cup as claimed in claim 1, wherein the method comprises the following steps: the hot-press shaping conditions of the step 6 are as follows: the pressure intensity is 50-70 kg/cm²The temperature is 170-230 ℃ and the time is 20-40 s.

10. The method for preparing the full-degradable fluoride-free pulp molding seedling raising cup as claimed in claim 1, wherein the method comprises the following steps: the ratio of the oven dry weight of the chemical medicines such as the waterproof agent, the dry strength agent, the wet strength agent and the like to the oven dry weight of the paper pulp fiber in the step 3 is as follows: 0.8-1.6 parts of waterproof agent, 0.6-1.2 parts of dry strength agent and 0.6-1.2 parts of wet strength agent (the absolute dry fiber amount of paper pulp is 100 parts).

11. A nursery cup product obtained by the method for preparing a full-degradable fluorine-free paper pulp molding nursery cup according to any one of claims 1 to 10.

Technical Field

The invention belongs to the technical field of paper pulp seedling raising cup production.

Background

Seedling transplantation is an important means for high yield and high efficiency in modern agriculture, but the current seedling transplantation is difficult to further enlarge the scale, mainly because a seedling container cannot be kept up with the seedling transplantation, the air permeability of a seedling plastic bag (pot) is poor, the seedling reviving period is long, and serious environmental pollution is caused. In some places, manual pot making is adopted for seedling raising, time and labor are wasted, and in addition, soil or sticky sand in many areas is difficult to make pots and is difficult to popularize in a large area.

In order to impart water-and oil-repellent functions to products, fluorine-based water-and oil-repellent agents such as PFOA (perfluorooctanoic acid and salts) and PFOS (perfluorooctane sulfonyl compounds) are most commonly used, but they are hardly degraded in the natural environment, have bioaccumulation and various toxicities, and have common characteristics of persistent organic pollutants, and are considered as novel persistent environmental pollutants which have been intensively studied in the 21 st century. For a seedling raising cup which is environment-friendly, the fluorine-containing water-proof and oil-proof agent cannot be used.

Pulp molding is a three-dimensional paper making technology, which takes waste paper, wood pulp or other plant fibers as raw materials and uses a special mold to mold a pulp product with a certain shape on a molding machine. It has four major advantages: 1. the raw materials are waste paper, wood pulp or other plant fibers, including paperboard, waste paper box paper, waste white edge paper, softwood pulp, hardwood pulp, bamboo pulp, bagasse pulp and the like, and the sources are wide; 2. the manufacturing process is completed by the working procedures of pulping, adsorption molding, drying and shaping and the like, the flow is short, and the environment is not harmful; 3. the product can be recycled; 4. the volume ratio of the foamed plastic is small, the weight is light, the plastic can be overlapped, and the transportation is convenient.

Disclosure of Invention

The invention aims to provide a novel fully-degradable fluoride-free paper pulp molded seedling cup and a preparation method thereof, which can realize complete soaking culture in water, natural hydrolysis at the later stage of a growth cycle, no harm to the environment and no need of manual recovery.

The invention is realized in this way, a preparation method of a full-degradable fluoride-free paper pulp molding seedling cup, comprising the following steps:

step 1: the paper pulp raw materials are measured according to the proportion, a hydraulic pulper is used for pulping to obtain pulp, and the concentration of the pulp obtained by pulping is 3.5% -4.0%;

step 2: defibering the treated pulp by using a dual-function defibering machine, and cutting, splitting and attenuating fibers by using the defibering machine to obtain uniform pulp;

and step 3: mixing the pulp with white water, adding chemical medicines such as a waterproof agent, a wet strength agent, a dry strength agent and the like, and uniformly stirring to prepare mixed pulp;

and 4, step 4: conveying the mixed slurry to a forming machine through a pipeline, and performing vacuum filtration and dehydration to obtain a wet embryo of the seedling cup;

and 5: spraying wet embryos of the seedling cup: adding silicon dioxide nanoparticles into a polymethyl methacrylate-ethyl acrylate polymer solution at 40-50 ℃, stirring for 10-20 minutes, then adding an ethanol solution, uniformly stirring, and spraying on the surface of a wet embryo of a seedling cup;

step 6: and (3) dehydrating, hot-pressing for shaping, transferring and trimming the sprayed wet blank of the seedling cup to obtain a finished product of the fully-degradable fluorine-free paper pulp molded seedling cup.

Further, in the step 1, the paper pulp raw materials are sugarcane pulp and bamboo pulp, and the ratio of the raw materials to the raw materials is 30-40: 60-70 wt%.

Further, in step 2, the mass of the slurry is as follows: the wet weight is 14-17 g, the beating degree is 20-23 DEG SR, and the viscosity is 60-70 Pa.s.

Further, in the step 3, the waterproof agent is fluororesin-free, the wet strength agent is polyamide-polyepichlorohydrin resin, and the dry strength agent is starch and a modifier thereof, and is a food-grade commercially available product. The addition amount of chemicals such as the waterproof agent, the dry strength agent, the wet strength agent and the like is determined according to the absolute dry pulp ratio according to the size of the prepared pulp, and the ratio of the chemicals such as the waterproof agent, the dry strength agent, the wet strength agent and the like to the absolute dry pulp fibers is further selected as follows: 0.8-1.6 parts of waterproof agent, 0.6-1.2 parts of dry strength agent and 0.6-1.2 parts of wet strength agent (absolute dry fiber is taken as 100 parts).

Further, in the step 3, pulp is mixed with the white water according to DCS setting, the concentration of the mixed pulp is 0.27-0.32%, and the pulp mixing time is 15-25 min.

Further, the operation parameters of the dehydration treatment of the pulp molding wet blank in the step 4 are as follows: and (3) dehydrating for 15-20 s under the suction negative pressure of-0.03 MPa to-0.035 MPa until the water content is 65-75%.

Further, the step 5 of preparing the spray coating comprises the following steps:

dissolving 1.5-2.0 wt/v% of polymethyl methacrylate-ethyl acrylate polymer in a toluene solution, stirring for 10-20 minutes at 40-50 ℃, adding silicon dioxide nanoparticles (the mass ratio of the silicon dioxide nanoparticles to the polymethyl methacrylate-ethyl acrylate polymer is 1.5-2.0: 100) with the particle size of 15-25 nm, and stirring for 10-20 minutes. And finally, adding an ethanol solution (the volume of which is consistent with that of the toluene solution), stirring for 1-2 minutes, and spraying on the wet embryo. The spraying amount is as follows: 1-5% of the weight of the absolutely dry paper pulp fiber.

Further, in step 6, the hot press setting conditions are as follows: the pressure intensity is 50-70 kg/cm²The temperature is 170-230 ℃ and the time is 20-40 s.

The invention has the beneficial effects that: the invention adopts bamboo and common crop waste as the raw materials of the slurry, and the prepared product is a green environment-friendly fully-degradable material, so that no environmental pressure exists from the source to the finished product. The product can be directly discarded after being used and can be naturally degraded into soil for planting; or the soil is crushed and reduced into planting soil for reuse or discarded. The non-fluorine water repellent agent is adopted, a better water-resistant and anti-seepage effect is obtained, the cup can be used as a seedling cup for a long time, and meanwhile, the cup has a remarkable yield increasing effect.

Detailed Description

The following examples are given to illustrate the practice of the present invention in detail. The technical parameters and auxiliaries which are not specifically mentioned in the examples below can be selected routinely and adaptively by the person skilled in the art on the basis of the knowledge in the technical field.

The preparation method of the wet blank spraying chemical material of the pulp molding seedling raising cup provided by the invention is shown in the following examples 1 and 2: