Polypropylene (PP)

Polypropylene Poly(propylene)

(1) Production Process of Polypropylene (PP) Polypropylene is composed of propylene, CH2=CHCH3, polymerized by ZN metal catalyst.

(2) Production method of polypropylene (PP) 1 Slurry method. Polymerization in diluents such as hexane is the earliest industrialized and also the most productive method ever produced.

2 liquid phase bulk method. Polymerization in liquid propylene at 70°C and 3 MPa.

3 gas phase method. The polymerization takes place under the gaseous conditions of propylene. The latter two methods do not use thinner, the process is short, and the energy consumption is low. Liquid-phase mass spectrometry has now shown its advantages of being the first to come. Gas-phase methods are also rapidly developing.

Polypropylene classification is divided into isotactic polypropylene and atactic polypropylene according to the structure.

The commonly used polypropylene is isotactic polypropylene.

Characteristics of PP Its molecular structure is similar to that of polyethylene, but the carbon atoms on the carbon chain have a methyl group (–CH3). Polypropylene is slightly more brittle than polyethylene and has a melting temperature of 160°C.

Usually translucent colorless solid, odorless and non-toxic.

Because of the regular structure and high degree of crystallization, the melting point of up to 167 °C, heat, steam sterilization products is its outstanding advantages.

Density 0.90g/cm3, is the lightest universal plastic.

Corrosion resistance, tensile strength 30MPa, strength, rigidity and transparency are better than polyethylene.

The disadvantages are poor low-temperature impact resistance and easier aging, but they can be overcome by modification and addition of antioxidants, respectively.

Application of PP (1) Injection Molded Products: It is the largest application area of ​​polypropylene. The products include turnover boxes, containers, suitcases, auto parts (automotive interior parts, such as dashboards; fenders, ventilation ducts, fans; insurance Bars), Household Appliance Parts, Medical Devices (Disposable Syringes), Instruments (Disher Door Liners, Dryer Vents, Washer Frames and Covers, Refrigerator Door Liners, etc., Household Consumer Goods (Lawns and Gardening Equipment) Such as lawnmowers and sprinklers, etc.) and furniture.

(2) Extruded products: Made of polypropylene fiber, polypropylene film can also be made, in which the strength and transparency of the biaxially stretched film are greatly improved, and it is an important polymer material for packaging.

Polypropylene is the most widely used general-purpose plastic. It can be used as plastic or spun into fibers (PP). Polypropylene is a low-absorbency, high-corrosion fiber that can be used in clothing and furniture, especially for woven carpets. It can also be extruded or blow-molded into thin films, then cut into flat strips for drafting, making woven bags, or as a strapping material - packing tape. Polypropylene composite films have developed rapidly in recent years and can be used for moisture, air separation and cooking, and are used as flexible food and beverage packaging.

Polypropylene pipes are used to deliver hot water - PPR pipes, industrial waste water and chemicals.

Plates are used to make containers.

(3) Thermoformed products: Sheets are thermoformed to form thin-walled products that are used as disposable food containers – drinking cups.

Others, such as blow molded products, polypropylene is widely used in food packaging, such as yogurt containers, hot-filled beverage bottles. toy. Polypropylenes with isotactic and random segments, respectively, can also be made by special catalytic methods (metallocene catalysis). This polypropylene is similar in properties to rubber.

Cationic Dyes are a class of Basic Dyes. Dyeing speed, poor levelness, high color yield, with the retarding agent can be dyed dark.

Cationic dye affinity for acrylic big, due to the adsorption of fast and slow diffusion staining, easy to produce uneven dyeing phenomenon, and once produced uneven dyeing, dyeing difficult by extending the method to correct time. Cationic Dyes, in order to obtain uniform staining, dyeing rate should be appropriately reduced. Factors affecting the rate of cationic dyes in addition to the type of acrylic, there are temperature, pH value of the dye bath, electrolytes, retarding agent.

Basic/Cationic Dyes

Cationic Dyes, Basic Dyes, Basic Orange Dyes, Liquid Cationic Dyes

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