Winter construction of concrete admixtures

In the process of construction management, the commonly used concrete admixtures are early-strength admixture, superplasticizer, retardants, antifreeze agents and so on. Following are the brief introduction of several kinds of admixtures used in the winter.

1 Water Reducing Agents

Use water reducing agents can reduce the moisture content of the concrete, make the ice crystals fine and uniform, further reducing destructive power of ice water on the concrete. Thus, water reducing agent used in winter construction of concrete is essential. Currently, the more common varieties of water reducing agent are:

(1) lignin sulfonate (calcium or sodium) common reducing agent;

(2) naphthalene sulfonic acid formaldehyde condensation product superplasticizer;

(3) polycyclic aromatic sulphonate formaldehyde condensation product superplasticizer;

(4) formaldehyde condensation product superplasticizer melamine sulfonate;

(5) the aliphatic superplasticizer;

(6) polycarboxylate water reducing agent;

(7) modification of lignin sulfonic acid calcium (or sodium) of superplasticizer.

Naphthalene water reducing agent and aliphatic water reducer is the main kind Winter construction. Besides, early strength composite components of polycarboxylate water reducing agent in winter construction of concrete is more common.



2 Air-entraining Agents

Add air-entraining agent can introduce closed tiny pores (air content in 3%-5%) in concrete and these pores can buffer produced by mixing water ice volume expansion. This helps to resistance to early frost damage and improve the durability of hardened concrete. According to chemical composition of air-entraining agent can be divided into the following categories:

(1) wood resin acids;

(2) the detergent category;

(3) lignin sulfonate salts;

(4) oil acid salts;

(5) hydrocarbon organic sulfonic acid salt.

When it is needed to be air entrained concrete in winter construction, air-entraining water-reducing agent can also be used, such as sodium calcium lignosulphonate, wood and polycarboxylic series of water reducing agent.

In addition, rust inhibitor in reinforced concrete engineering to reduce or prevent corrosion of metal embedded in concrete to improve the durability of concrete in winter construction. If you have interest in construction chemicals of OKCHEM, please read more here!
Source: https://www.okchem.com/news/winter-construction-concrete-admixtures.html

Daily chemicals in our life

The main ingredients of daily chemicals are surfactant of anionic, non-ionic, amphoteric, cationic, then is function additive.

Kitchen detergents can be roughly divided into fresh food, tableware detergents and kitchen detergents. There are many strict requirements to food and food containers. So, the composition of kitchen detergents and washing method has its particularities.
As dishwashing detergent pay more attention to decontamination ability and bubble functions, so dishwashing detergent generally do not use low foaming surfactant.

The commonly used surfactant of hand dishwashing detergents has sodium linear alkyl benzene sulfonate (LAS), fatty alcohol polyoxyethylene ether sulfate (AES), Allah--vinyl sulfonate (AOS), fatty acid alkanolamide, fatty Alcohol Ethoxylates (AE or AEO), fatty alcohol sulfates(FAS), alkyl sulfonate (SAS), amine oxide, alkyl glycosides (APG). LAS, AES, FAS, SAS, SOS is the main component of hand dishwashing detergents.



Coconut powder, coconut oil can make the kitchen cleaner more lubrication, they are effective to clean. Coconut powder is made from coconut, it is a fruit with a high nutritional value. The effect of coconut powder and coconut oil is lubrication. We can better protect the skin when use with this component.

Dishwashing detergent rarely using just one surfactant. Two or more than two kinds of surfactant tends to have better washing effect than single surfactant. Commonly used system are LAS/AES; LAS/AE/FAA; AES/OA; AES/AOS/OA; etc.

Concentrated laundry detergent mainly consists of high content surfactant as the main actives, and accompanied by sodium carbonate, silicate, anti-redeposition agents and other additives. Some products also have functional additive ingredients such as bleaching and sterilization.

Softeners has powder and liquid two kinds. Softening agent can solve the problem of rough feel, and it can make the surface and inside of the fabric smooth.

Toilet cleaners and kitchen cleaners are different. Toilet cleaners contain pesticides, sodium hypochlorite bleach and other chemicals, so toilet cleaner is acid. Kitchen cleaners are mainly fatty alcohol polyoxyethylene ether, polyethylene glycol cocoate, ethylene glycol monobutyl ether, propylene glycol butyl ether and 0.5% of ammonia, so the kitchen detergent is alkaline. If you have interest in daily chemicals such as kitchen cleaners, fabric cleaners, toilet cleaners, personal care chemicals, etc, please click here for more directly!
Source: https://www.okchem.com/news/daily-chemicals-life.html

Composition and classification of plastics

The plastics that we usually use is not a pure substance, it is made of many materials, and polymer (or synthetic resin ) is the main component of plastic. Besides, it also need to add a variety of auxiliary materials to the polymer to improve the performance of plastic, such as fillers, stabilizers, colorants, plasticizers, lubricants, etc. Thus it can become a high performance plastic.

Synthetic resins is the main components of plastic, their content in plastic is 40%~100%. Due to the large content and its properties often determine plastic properties, so resin is often viewed as synonymous with plastic. Actually, resins and plastics are two different concepts. Resin is the original polymer, it is not only used to make plastics, but also paints, adhesives and synthetic materials. But a tiny part contains 100% resin, the vast majority of plastic need the main components resin and other substances.

Fillers can increase strength and heat resistance performance and reduce costs. Adding wooden powder to phenolic resin can greatly reduce costs, this makes bakelite became one of the most cheapest plastic, also it can significantly improve the mechanical strength. There are organic fillers and inorganic fillers, the former has wood powders, rag, paper and fabric fibers, etc; the latter are glass fibre, diatomaceous silica, asbestos, and so on.



Plasticizers can increase plasticity and flexibility of plastic, reduce the brittleness and make it easy for plastic processing. Plasticizers are high-boiling organic compounds that generally mixed-soluble with resin, nontoxic, odorless, light and thermal stability, the most commonly used are phthalic acid esters. For example, soft PVC can be obtained if add more plasticizer when producing PVC, if add less or not add plasticizer it can get rigid PVC.

In order to prevent synthetic resin has light and heat of decomposition and destruction during processing and use, and extend the service life, it needs to add stabilizer to plastic. Commonly used are stearate, epoxy resin and so on.
It can be divided into thermoplastic and thermosetting plastic according to the nature of plastic heating.

Thermoplastic molecular structure is linear structure, soften or melt when heated, it can be made into a certain shape, cooling and hardening. Heated to some extent it soften again, cooled and hardened. This process can be repeated several times.

Molecular structure of thermosetting plastics is the body structure, softens when heated. It can plastic into definite shape, but heated to a certain degree or after adding a small amount of stabilizer, then hardened stereotype, it does not become soft and change its shape when reheating. Heating won't make it soften after processing of thermoset plastic, therefore, it cannot be recycled. Bakelite, amino plastics and epoxy belongs to this type of plastic. Molding process of thermoset plastic is complex, so continuous production is difficult, but it has good heat resistance, not easy to deformation and relatively inexpensive. If you think this is helpful and have interest in plastic raw materials, you can click here directly!
Source: https://www.okchem.com/news/composition-classification-plastics.html

Several catagory of plastic raw materials

Plastic raw materials is polymer or macromolecules, it also commonly known as plastic or resin. The so-called plastic raw materials is one kind of synthetic resin, the shape is similar to natural resins of pine resin, but it is synthesized by chemically force, so it is known as plastic.

According to various using, plastics are usually divided into general plastics, engineering plastics and special plastics.



General plastics generally refers to the large production, wide use, good forming and cheap. There are five major varieties of general plastics, namely, polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS) and acrylonitrile-butadiene-styrene copolymer (ABS). These five plastic occupies most of the plastic materials used, the rest can be categorized into special plastic variety, such as PPS, PPO, PA, PC, POM etc, they are rarely in daily life products and mainly used in the engineering industry, high-end fields such as science and technology for national defense, such as automotive, aerospace, construction, communications and other fields. Classification of plastics according to its plasticity can be divided into thermoplastic and thermosetting plastics. Typically, thermoplastic plastic products can be recycled, but thermosetting plastics cannot. According to the optical properties of plastic, it can be divided into transparent, translucent and opaque material, and PS, PMMA, AS, PC belongs to transparent plastic, and most other plastic are opaque plastic.

Engineering plastics refers to be able to withstand forces and has good mechanical properties, high temperature resistance, low temperature resistance and good dimensional stability, as well as can be used as structural plastics, such as polysulfone and polyamide. Engineering plastics can be divided into general and special engineering plastics. General engineering plastics includes polyamide, polyacetal, polycarbonate and modified polyphenylene ether thermoplastic polyester, ultra high molecular weight polyethylene, methyl pentene polymer, vinyl alcohol copolymers. Special engineering plastics has crosslinking of non-cross-linked. Crosslinking are double maleamic polyurethane, poly-triazine, crosslinked polyimide, heat-resistant epoxy resin and so on. Non-cross-linked are polysulfone, PES, polyphenylene ether, polyimide, polyether ether ketone (PEEK), etc.

Special plastics has special function and can be used for special applications such as aviation, aerospace. For example, fluorine plastic and silicone has outstanding resistance to high temperature, lubrication and other special functions. It enhances plastics and foams with high strength, high buffering and other special properties, which belong to the category of specialty plastics. More information about plastic raw materials, please click here. Hope this is helpful to you, thanks!
Source: https://www.okchem.com/news/several-catagory-plastic-raw-materials.html

Coagulants & Flocculants in water treatment

Coagulants & Flocculants is very important operation in various water and wastewater processing, because it decides follow-up process of run situation, eventually water of quality and run cost. The coagulation process can reduce water COD value, remove suspended real and colloidal particles in water, and also remove bacteria and virus in water. Besides, it has the role of phosphorus removal, decolorization, deodorant and mitigation of eutrophication in water.

Coagulant has inorganic and organic compounds. Inorganic compound mainly are water-soluble of bivalent or trivalent metal salts. Flocculant is organic polymer, most are high molecular weight and has particular electric and the charge density.



Commonly used inorganic flocculants are aluminum sulfate, alum, ferric chloride, ferrous sulphate, polyferric chloride is the new coagulant developed in the past half a century. Due to their combination of coagulation and flocculation functions, the efficacy can be multiplied compared with traditional pharmacy, it gradually become the mainstream pharmaceutical water treatment industry. Organic coagulant mainly are polyacrylamide, polyamine, etc.

Coagulation and flocculation are included in coagulation treatment. In condensed phases of water gel double layer is compressed and lose stability to form small particles; during flocculation stage such coalescence with each other to form larger particles Floc, these flocs can separate from the water removed in certain precipitation conditions.

In the practical application, as coagulants/flocculants are polymer materials, large and small molecules are in the same product, the so-called "molecular weight" is just an average concept. Therefore, when a wastewater treatment with a certain coagulant or Flocculent, "neutralization" and "bridge" are intertwined at the same time. Flocculation is the result of many factors, there are still some not to identify and solve problems at present.

As all we know, flocculation is related to coagulation agents molecular structure, molecular weight, charge density; also related to surface properties of suspended particles, particle concentration, surface area; related with medium (water) pH value, conductivity and other substances in the water, water temperature, agitation and other factors. In spite of theory and experience, select a flocculant by test is still indispensable. If you have interest in water treatment chemicals, please click here to get more!
Source: https://www.okchem.com/news/coagulants-flocculants-water-treatment.html

Why need paper coating process? Because paper fiber is no longer loose arrangement and it has some tightness after calendering. But the smoothness of the surface still does not meet the requirements of high-end fine print. The non-coated paper has poor surface uniformity, the printing ink is not uniform and low gloss, it cannot make the tiny dot restored, then it results in level loss and some uniformity in the field of the image decline, this affect the printing effect, thus fine printing paper needs paper coating processes to further improve the paper surface properties.

Lots of materials for paper, such as plant fibers and animal fibers, organic and inorganic, metal and so on. Coating additives can improve the quality of paint, give special properties or make coating operations normal. This series of chemicals mainly are: dispersant to reduce the high concentration of paint viscosity to make it has good rheological properties; lubricant can be used to build paint rheology, reduce the friction coefficient and reduce sticking phenomenon of of coated paper in super calendering; solvent resistance to increase water resistance of starch and casein, PVA and other coating adhesive; paint rheology modifiers used to adjust the viscosity of the paint to suit a variety of coating process. Viscosity reducing agent is to reduce the viscosity of paints, such as urea, dicyandiamide, etc. While thickener or super absorbent polymers is to increase viscosity of paints, such as acrylates copolymer, cellulose derivatives, and so on. Viscosity reducing agent can make paint maintain appropriate rheological properties, avoid coated paper peeling, streak or arching problems. Also, it needs to add defoaming agents, preservatives, fluorescent whitening agents and other additives during the coating process.



Coating adhesive can make the pigment bonding with each other in coating process. The traditional use of coating adhesive are casein, soybean protein, oxidized starch and polyvinyl alcohol and other natural or synthetic compounds, in the 1950s developed of styrene-butadiene LaTeX, acrylic emulsions, polyvinyl acetate, then is Carboxylated styrene-butadiene LaTeX which used as adhesive coating can improve mechanical stability and increased brightness coated paper and printing ink. It has taken the place of casein and used as the primary binder. After the oil crisis, mix use of synthetic LaTeX mixed and starch phosphate ester and other starch derivatives to ensure quality and reduce the cost of adhesives.

Purpose of paper coating is to cover a layer of paint consists of fine particles that has good absorption to inks on the surface formed by fibers of the rough and plain paper with large pores. This in order to obtain a good uniformity and smoothness of the paper. It also improves gloss, stability and opacity of the paper through coating, and these characteristics increase with the increase of coating. If you have interest, view more here!
Source: https://www.okchem.com/news/knowledge-paper-coating.html

The common polymers

Polymer refers to macro molecular compound, one or several structural units connected by covalent bonding of high molecular weight compounds. Most natural polymers exist in the organism, and it is essential for life.

These natural polymers some are important nutrients, such as protein, starch; some can be used for daily necessities, such as natural rubber, cellulose; some can control our genetic in organisms, such as nucleic acid.

Synthetic polymers are usually high molecular weight organic compounds. Compared to natural polymers, its structure is simple, usually a maximum of two different units, such as nylon, polyvinyl chloride (PVC), etc.

There are common polymers, such as polyurethane. In addition to urethane, polyurethane macromolecules also contain ether, ester, urea, biuret, urea acid ester and other groups. According to the different raw materials, there has a different nature of the products, they usually are polyester and polyether-type. It can be used in the manufacture of plastics, rubber, fibers, rigid and flexible foams, adhesives and coatings.

Poly ethylene glycol and Poly ethylene oxide are made by polymerization of ethylene oxide, but the synthesis method and the molecular weight is different. Generally, PEG refers to polymers of molecular weight in 500-20000, molecular weight of PEO is 100000-5000000. From moleculars perspective, the main difference of this two is molecular volume different, second is synthesis of catalysts and way of different. Generally, molecular chain ends of PEG are hydroxy, but one end of PEO molecular is hydroxy, the other is alkyl. Due to the features of polymer material, different molecular volume will led to larger differences of performance. It can be said as two different materials from using, but it is not appropriate to say the two materials are fundamental different.



Polymer refers to high molecular weight (usually up to 104~106) compounds that through covalent bonds repeated connection of many of the same, simple structure.

Classification of polymers can be from different angles, such as single sources, synthesis, end use, heating, polymer structure and so on. If you have interest in polymer and need more details, please read more here now.
Source: https://www.okchem.com/news/the-common-polymers/

Synthesis adhesives and uses

From the application structure of adhesive, packaging industry is the largest industry of adhesives application. It is widely distributed in paper products, printed decoration, plastic and other packaging industry. Meanwhile, with the development of adhesives industry, it improves the quality and grade of packaged products and promote the development of the packaging industry.



Synthesis adhesive is composed by main agent and additives. Main agent is called main ingredient, base material or stick material; additives are curing agent, diluted agent, plasticizer, filler, coupling agents, initiator, thickeners, anti-old agent, polymerization inhibitor, stabilizer, complexing agent, emulsion agent and so on. According to requirements and uses, it also can be the components of flame retardant agent, sent bubble agent, elimination bubble agent, coloring agent, antifungal agents, etc.

According to the different raw materials, hot melt adhesives can be divided into EVA hot-melt adhesive, polyamide hot-melt adhesive, polyester hot melt adhesive, polyolefin hot melts, etc. Currently, EVA hot-melt adhesive is the major production and use one. The main raw material of adhesive for polyolefin series is vinyl series, SBS, SIS polymer body.

Synthetic adhesives is mainly used in wood processing, construction, décor, automotive, footwear, packaging, textiles, electronics, printing and binding, and other fields. The main exported synthetic adhesives is formaldehyde poly vinyl acetate, polyethylene acid acetal and pressure-sensitive adhesive.

Polyurethane adhesive can adhesive various materials, it can still keep physical and chemical nature of the material after bonding at low temperature. It mainly used in footwear, packaging, automotive, magnetic recording materials and other fields.
Silicone adhesive is a seal adhesives with cold and heat resistance, aging resistance, waterproof, moisture-proof, retractable high fatigue strength, permanent deformation, nontoxic and so on. In recent years, such adhesives in China is developing rapidly.

Adhesives for wood processing is applied to medium-density fiberboard, gypsum board, plywood and particle board, etc.

Construction adhesives is mainly used in building decoration, sealing or bonding between the structures. With the development of construction industry, high-rise buildings and interior decoration, the consumption of construction adhesive has increased sharply. Building decorative adhesive such as polyvinyl acetate, POLYACRYLIC acid, VAE emulsion can basically meet the need in the domestic.

Due to its variety and different components, here will not explain each adhesive this time. If you have interest in adhesives such as natural adhesives and synthesis adhesives, please click here to get more!
Source: https://www.okchem.com/news/archives/825

Use and precautions of PP ink

Requirement of different printing processes for ink is not exactly the same, besides it must add appropriate supplementary components to make them easier to use in specific occasions. For example, the viscosity of offset printing inks is large and the water resistance is good, gravure inks is more dilute, good liquid; screen printing ink need to have good permeability.





The main difference of different printing process uses ink is the ink contains different additives. Characteristics of PP ink: without treatment, wear-resistant up to 6 levels, scratch-free up to 5 levels, alcohol tolerance, solvent, resistance to acid and alkali, good twists, good color matching, good weather resistance, fine and uniform ink for construction, low odor, nontoxic inks, etc.

The applications of PP ink are as follows: rigid PP, treatment of PE material such as stationery folders, medicine bottles, trademark, licensing, solution tanks, helmets, automotive parts, electronic parts, electrical accessories, specialty products, printing of polypropylene materials (PP) or spraying technology, etc.

PP ink applied on surface static, flame treatment or not treatment rigid PP and BOPP material of printing inks. Colour dispersion of PP ink is good, excellent adhesion characteristics, etc. Currently, it mainly used in the industries of plastics industry, packaging, decoration, silk screen printing or pad printing.

Precautions for use:

1 the adaptability of different materials on the ink is different, customers should test printing to determine compliance with requirements

2 ink may yellow and corroded packaging wall after long term storage, but this does not affect printing

3 adjustable gold and silver inks should be use promptly after adjusted, it cannot be stored

4 choose different drying rate of diluent according to the climatic and environmental changes

5 when ink completely dry, the new printing products can be packaged

6 please keep away from ignition source when in storage and use, and save in a dark environment

If you have interest in Printing Ink Raw Materials, PP Inks, pigments and other chemicals raw materials in OKCHEM, please read more here, thanks!
Source: https://www.okchem.com/news/use-precautions-pp-ink.html

Water reducing agent in concrete

There has two roles on concrete quality when mixed the right amount of water reducing agent with concrete:

1 Mixed with the right amount of water reducing agent without changing the case of a concrete mix ratio and water/cement ratio, which can enhance the fluidity of concrete without reduce the concrete strength.

2 Water/cement ratio can be reduced while maintaining the fluidity and cement use amount unchanged. Due to the reduction of water consumption makes concrete density increase, thereby increase the strength and durability of concrete.

According to the composition of materials, water reducing agent can be divided into water sulfonate, polynuclear aromatic salts and water-soluble resin sulfonate. Sort by setting time it can be divided into standard type, early strength and retarding type. In accordance with the participation of composition, it can be divided into ordinary water reducers, superplasticizers, early strength water reducer and air-entraining water reducing agent.



The economic effect of adding water reducing agent to concrete are as follows:

1 keep the mix ratio of concrete unchanged, this can significantly increase the fluidity of concrete;

2 maintain the fluidity of concrete and cement usage does not change, it can reduce the amount of water and increase strength;

3 maintain the fluidity and strength intact to reduce the amount of cement;

4 keep the concrete liquidity requirements unchanged can reduce the amount of water and increase the frost resistance and impermeability of concrete;

5 delay the hydration of cement and reduce the thermal stress of mass concrete, as well as reduce the possibility of cracking.

Studies show that after joining the reducing agent, the hydrophobic group of reducing agent oriented adsorption on the surface of cement particles, hydrophilic point to the aqueous and form a single molecule or molecules adsorbed film.
Due to the adsorption dispersion, moist and lubricated, just use a small amount of water can easily mix concrete evenly, so as to improve the workability of the fresh concrete.

Because of the dispersion of water reducing agent, this keeps the cement particles more isolation and makes early hydration increases the reaction area of cement particles. Hydration reaction of cement of this stage in the process of dissolution - hydration - crystallization. While filming of water reducing agent would hinder the reaction, but its impact is small,but its overall effect is to increase the speed of initial hydration. If you have interest in water reducing agent and other construction chemicals, please click here!
Source: https://www.okchem.com/news/water-reducing-agent-concrete.html

Application of TPE

TPE has excellent weatherability, coloring, temperature resistance, as well as good process performance. It not only secondary injection molding, coating and adhesion with PP, PE, PC, PS, ABS and other body material, but also separately molded. It is nontoxic and security.

Thermoplastic Elastomer (TPE) is widely used in various fields



TPE applications in the field of wire and cable

Traditionally wires and cables mostly use PVC as insulation and coating materials, because of environmental problems caused by PVC material, this replaced by TPE materials.

TPE applications of kitchen and sanitary ware

TPE material can fully play a role in the grease and moist environment of kitchen and toilet. Kitchen handle wrapped with TPE is anti-slip and comfortable, kitchen knife and scissors with slip circle package is more solid and more security.

TPE application of tool handles

In a way of two materials-plastic, TPE applied to tool handles, it provides products with non-slip and shock-absorbing, soft and warm comfort, as well as improve durability and value of products. Oil-proof and soft anti-slip properties of TPE makes electric drill more reliably in the greasy dirt and dust work environment.

TPE application of baby products

Baby products requires a more high level of safety and health, the soft, high toughness and nontoxic properties of TPE just meet the strict requirements of the product.

TPE application of sports equipment

With excellent weather resistance and chemical resistance, TPE used in outdoor sports equipment has better performance than traditional rubber. Water supplies such as flippers, goggles, etc can still maintain good flexibility and resilience after seawater immersion and after sun exposure.

TPE application of airbag

TPE have a good air-tightness, elastomer PP plastic bags allow the airbag a better dispersion and cushioning impact.

Thermoplastic Elastomer is a combination of rubber and plastic properties of materials. It displays rubber elasticity at room temperature and plastic molding of polymer materials at high temperatures.

There are many different varieties of thermoplastic elastomer materials in OKCHEM, characteristic and application of the different kinds of TPE is different. For example, styrenic thermoplastic elastomers (TPS), thermoplastic polyurethane elastomer (TPU), PP/EPDM blending modification of TPV thermoplastic elastomers, Polyolefin elastomers (TPO) and thermoplastic polyester elastomer (TPEE). If you have interest in plastic raw materials such as TPE, please click here!
Source: https://www.okchem.com/news/application-of-tpe.html