Cellulose precipitation dispersion mixer

High shear mixing and dispersing machine for settling fiber slurryAramid precipitation fiber disperser, chitosan precipitation fiber disperser, cellulose precipitation fiber disperser, polymer precipitation fiber disperser
(For details and prices, the consulting company has a prototype that can be tested for free!)

1、 Product Name:Cellulose precipitation dispersion mixer

2、 Preparation and properties of precipitated fibers
Precipitated fiberIt is formed instantaneously in a high-speed and high shear coagulation bath by the polymer industry, with a time of about 10-5 seconds. Therefore, the control of various influencing factors during the formation of precipitated fibers has an important impact on their properties. Fiber precipitation is carried out using isophthalic chloride and isophenylenediamine as polymerization monomers to prepare meta aramid fibers with different molecular weights in the dimethylacetamide system; The triethanolamine hydrochloride salt generated during the reaction process is removed using triethanolamine, and after filtration, a meta aramid solution is obtained; Using DMAc/H2O mixed solution as the coagulation bath for aramid precipitation fibers; After the rotational speed stabilizes, extract and filter the interstitial aramid solution with a syringe. Inject the aramid solution into the high shear coagulation bath along the middle of the cylinder at a rate of 1:20 to 1:100, with the volume ratio of the aramid solution added at once to the volume of the coagulation bath inside the cylinder; The precipitated fibers are formed at the moment when the meta aramid solution is injected into the coagulation bath.
3、 Size and application of chitosan precipitated fibers
Chitosan precipitation fiberThe size of chitosan microcellular precipitated fibers prepared from chitosan solution is relatively stable, with a diameter range of 1-3 μ m and a length of 100-300 μ m under humid conditions. This precipitated fiber size is suitable for manufacturing non-woven fabrics for hygiene. In the process of forming precipitated fibers, the polymer solution can first be regarded as a non Newtonian fluid with certain viscoelasticity, which is rapidly stretched and deformed by the shear force of the liquid in a high-speed shear coagulation bath. While the polymer solution is stretched and deformed, the coagulant penetrates into its interior through the interface between the coagulation bath and the polymer solution. As the concentration of the coagulant inside the polymer solution increases, the polymer solution gradually transitions from liquid to solid. The polymer solution is stretched and deformed, the coagulant penetrates into the interior of the solution, and the polymer solution gradually transitions from liquid to solid, all at the same time, until a critical value is reached - the shear force of the high-speed shear coagulation bath can no longer cause deformation of the gradually solidified polymer droplets, thus forming precipitated fibers.
In the preparation process of precipitated fibers, the properties of polymer solution (concentration, viscosity, temperature, ion content, etc.), coagulation bath properties (solvent to coagulant ratio, coagulation bath temperature, ion concentration, etc.), and shear rate (greater than 12 s-1) are the main factors affecting the formation and properties of precipitated fibers.

Application of sedimented fibers: aramid paper and its composite materials, biomaterials

At present, most of the research on precipitated fibers at home and abroad focuses on the selection and optimization of preparation processes, as well as the observation of the morphology and size of precipitated fibers. However, there has been a lack of in-depth and systematic research on the relationship between various factors in the preparation process and the morphology, size, and properties of precipitated fibers, especially on the formation mechanism of precipitated fibers. Therefore, future research will focus on the following areas
(1) Settling fibers are formed in a high-speed shear coagulation bath, so stable shear rate is the main factor in preparing settling fibers with stable size and performance. Therefore, equipment that generates high-speed shear can be optimized for design;
(2) Metal ions not only have a significant impact on the forming process of precipitated fibers, but their residual content also has a key influence on the electrical insulation properties of precipitated fibers, aramid paper, and composite materials. Therefore, starting from polymerization, neutralizing agents that can replace metal salts can be selected;
(3) Currently, the preparation of precipitated fibers is mostly done at room temperature, and by adjusting the ambient temperature, the main performance influencing factors during the formation of precipitated fibers, such as the viscosity of polymer solutions and the diffusion coefficient of coagulation baths, can be controlled.

4 SIDCellulose precipitation dispersion mixerEquipment Introduction
High speed mixing and dispersing machine for settling fibersSpecially designed to mix and disperse powders that are difficult to dissolve in liquids, while minimizing the amount of air mixed in. The rotor/stator design generates strong shear forces, all pre hydrated, without "fish eye" dispersion side effects. The dispersion and mixing process only takes a small amount of time, does not have excessive effects on shear sensitive products, and can be processed in a cyclic manner.

5、 Principle of SID sedimentation fiber mixing and dispersing machine equipment
High shear mixing and dispersing machine for settling fiber slurryBy utilizing the high-speed rotation of a special rotor to generate a vacuum, the powder is uniformly sucked into the hopper or working chamber and evenly distributed in a rapidly flowing liquid flow. In the liquid flow, the powder is instantly wetted without producing agglomerated lumps. Due to the uniform wetting of the powder by the liquid flow from the beginning, there is no un wetted powder, and no crust formation on the surface of the liquid flow, stirring shaft, and container wall. Traditional craftsmanship is prone to forming hard crusts. It can be seen that using PLM system can greatly improve the quality of products. The main reason for the reduction of dust is that the vacuum is generated by the liquid, and all the powder is introduced into the liquid flow without any residue. The environmentally friendly auxiliary facilities necessary for traditional processing techniques will no longer be needed here.
From the perspective of equipment, there are several factors that affect the dispersion effect, including:

1. Form of dispersion head (batch and continuous) (continuous is better than batch)

2. Shear rate of dispersing head (the higher, the better the effect)

3 dispersed head tooth structure (divided into initial teeth, middle teeth, fine teeth, ultra-fine teeth, with fine teeth having better effect)

4. The residence time of materials in the dispersed wall and the emulsification dispersion time (can be regarded as the same motor, the smaller the flow rate, the better the effect)

5 cycles (the more, the better the effect, and by the end of the device's lifespan, it cannot be any better)

Calculation of linear velocity

The definition of shear rate is the relative velocity of the liquid layer between two surfaces.

- Shear rate (s-1)=v rate (m/s)
G distance between stator and rotor (m)

As can be seen from the above, the shear rate depends on the following factors:

- Linear velocity of the rotor

In this case, the distance between the two surfaces is the rotor stator spacing.
The spacing range between SID stator and rotor is 0.2~0.4 mm

Speed V=3.14 X D (rotor diameter) X rotational speed RPM/60

6、 SID sedimentation fiber high-speed mixing and dispersion equipment selection table:

note

*The flow range in the table refers to the data measured when the medium is "water";
*The amount of powder absorption depends on the characteristics of the powder itself (such as particle size, swelling ability, flowability, etc.). If it cannot be confirmed, please provide samples or select based on experimental data;
*If there are special working conditions, please provide detailed and accurate technical parameters and process requirements, and SID professional engineers will provide special design solutions;
*The data in this table is subject to change without prior notice, and the correct parameters are based on the actual product provided.
The following is a sample image of a successful case of Xide Company's sedimentation fiber production

7、 Performance and value of settling fiber mixing and dispersing machine
The high-speed mixing and dispersing machine for precipitated fibers applies high-speed shear force to the precipitated fibers. Under the action of centrifugal force obtained by the high-speed rotating rotor, the water-based precipitated fibers are simultaneously sucked into the working chamber from the feeding area of the working head in the axial direction. The strong centrifugal force draws the material radially into the narrow cavity gap between the stator and rotor, where it is subjected to centrifugal compression, liquid layer friction, hydraulic shear, and impact tearing, resulting in high porosity and porous precipitated fiber materials, as well as stable morphology, size, and performance of precipitated fibers. The SID high-speed mixing and dispersing machine has made certain progress in the research of cellulose precipitation fibers and the development of biopharmaceutical materials, as well as the application of aramid as insulation materials for electrical appliances
8、 SID sedimentation fiber mixing and dispersing machine application fields:
Food industry, biomedicine, daily care products, nanomaterials, coatings and inks, petrochemicals, printing and dyeing auxiliaries, paper industry, pesticides and fertilizers, plastics and rubber, power electronics, fine chemicals, and other industries. In the fields of new polymer materials, chemical materials, and fine chemicals such as graphene, asphalt, new lithium batteries, cosmetics, and pharmaceuticals, their applications are particularly extensive and widespread.

High shear mixing and dispersing machine for settling fiber slurryAramid precipitation fiber disperser, chitosan precipitation fiber disperser, cellulose precipitation fiber disperser, polymer precipitation fiber disperser