Plasticizer: green alternative trend of some use

For a long time, plasticizer DOP (dioctyl phthalate) and other phthalate products. With these additives in the food, pharmaceutical and industrial applications more widely, toxicity studies in it more and more attention. Found that when the blood inlet PVC storage bag body, the products that are found in the lungs with DOP. Although the DOP is carcinogenic to make people still debated, but because of its carcinogenic potential suspects, countries have taken the appropriate restrictive stearate lead  measures. At present, the domestic production of some of the main plasticizer properties, especially health, low toxicity, it is difficult to meet the environmental requirements.
Since the DOA higher production costs, the domestic PVC cling film producers substantially with DOP, DBP (dibutyl phthalate) as a primary plasticizer. This produced cling film, used in high fat meat products, or use it to wrap food in the microwave, the plasticizer into the food more opportunities, potentially harmful to human health. DOP plasticizer especially considering there is a potential cancer hazard, the international community has begun to take appropriate measures to limit the dibasic lead stearate  use. Countries around the world have accelerated the toxic plasticizer product development efforts, especially for plastic products with high hygiene requirements based applied research. However, in our country, has been eliminated or restrict the use of foreign plasticizers such as DOP is also a great market, and the production of new enterprises for the non-toxic plasticizer is not enough emphasis on the development and promotion. Due to low prices, the domestic market 80% plasticizer DOP, DBP and so on.
In recent years, the rapid development  PVC heat stabilizer for window of the plastics industry as a whole environment, there is a degree of development of plastic additives, but mainly on the volume growth. Face of the global plastic additives industry, large-scale production, product specification refinement, multi-functional and development trend of environmental protection, China's plastics additives industry enterprises should be the perspective of sustainable development, increase green plasticizer product development efforts , in the industrial scale, environmental performance, and product quality, value-added and other aspects of establishing development advantages, and strive to compete in the new round of international markets for the spot.

Synthetic lubricants synthesis of the main

Organic synthesis method and the system having a specific structure and properties of lubricants, such as silicone oil , silicone esters , phosphate esters, fluorine oil , ester oil and synthetic hydrocarbon oil. Synthetic lubricants to meet the general mineral oil can not meet the severe operating conditions ( such as aviation , aerospace, deep-sea exploration and nuclear industries ) application requirements. Performance titanium dioxide  by the use of synthetic lubricants can be divided into high and low temperature lubricants, fire resistant lubricants, extreme pressure lubricants, protective lubricants, anti-radiation lubricating oil, lubricating oil antioxidant , high vacuum lubricant oil, electrical and metalworking lubricants oil. Water-based liquid water-based liquid poor lubricating performance than oil , is generally not used for pure lubrication occasions . It is commonly used for the metal cutting process in the cutting fluid , to a  black iron oxide cooling , lubrication, cleaning and rust and other effects , but also for the hydraulic system . Commonly used in industrial water-based liquid is diluted with water from the oil-based emulsion , water -oil -and water-in -oil types . ① In the oil-in -water emulsion , the oil in small droplets dispersed in water , a liquid emulsion was translucent ( droplet diameter of 0.05 to 0.1 microns ) or milky liquid ( droplet diameter of 0.1 to 1 micron time ) . In order to maintain a certain stability of the emulsion , should be added to the liquid from the emulsifying surfactant. Oil-in -water emulsion  calcium zinc stabilizer Foreign Secretary is water, oil content is low , and so the cooling water flow are close to rust, poor lubricity . ② The water-in- oil emulsion , the oil the water , the benefits are not rust, viscosity, can be used as hydraulic oil.

What is produced by the human body lubricant

It has long been trying to apply the lubricant human , lubricants ( liquid ) most applications in clinical medicine in the early examination of the human body : a lot of medical equipment will be in -depth at different levels of the human body caused by mechanical injury , lubricants You can minimize the body tissue , mucosal damage. Early human lubricant is  tribasic lead sulphate glycerin and hydrophilic substance as the main component , was improved by adding glass , sodium ethyl cellulose , Kaposi mother and other ingredients, improved reducing sticky , balance pH , to try and human humoral similar , reducing the probability of occurrence of allergic symptoms .
Lubricants used in human sexuality also has a very long history , but early people used vegetable oils such as olive oil and so on. However, due to limited composition effect is not ideal , easily contaminated clothing , not easy to be absorbed by the body ; Later, people Acrylic processing aid  have tried to use Vaseline, baby oil , shower gel, massage oil, petroleum-based mineral oil as a lubricating substance ; these substances are often sticky too large and difficult to clean after use is likely to cause residues, even after use is likely to be blocked by both men and women the urethra , resulting in difficulty urinating pain , and it will destroy the carbon black  condom stable , resulting in unwanted pregnancies , which will be on the human body damage ; now on the market are mainly used in the human body lubricant sex lubricating ; human lubricant weak acidic PH value 5-7 , consistent with the vaginal environment , while its viscosity is 1500-2000mpa.s lubricating properties and is the body's secretions are not available , so the lubricant is not only excellent human body secretions supplements , better play secretions can not achieve smooth effect, the colorless , odorless , tasteless , non greasy characteristics , allowing people to fully enjoy the natural sex. While the use of more safe and convenient.

Zinc stearate, plays an important role in the coating

Zinc stearate is mainly used in paint wood primer , since filling role in enhancing polish . Transparency, transparency of the coating effect is small, especially for transparent primer. With the direct method zinc stearate manufacturers slowly increased competitive pressures in the domestic zinc stearate coating performance has been dramatically improved. Zinc stearate coating , in addition to focusing on grinding and transparent , but also some other factors such as oil absorption , thickening , particle size, dispersion , etc. on the overall performance of methyl tin stabilizer  wood have also been affected. Zinc stearate mainly in wood primer has several technical indicators affect its paint performance: 1, polish
In wood primer , grinding performance in the paint is a very important indicator , the usual test method is the same coating formulation , spray plate while at the same time grinding test , there is no fixed standard . 2 , in a transparent primer transparency , transparency direct impact on the aesthetic appearance of wood . Thus , the production of zinc stearate, water can not be used in the transparent wood , mainly because of too many impurities . The direct method in the production of zinc stearate is able to meet the requirements of purity , but also very high demands on the process , different production processes a great impact on the transparency , there may be slight differences on the process of transparency led to huge differences 3 , thickening production of coatings thickened manufacturers of zinc stearate is acceptable because zinc stearate added to the paint finished products , to determine its viscosity , the factory already settled indicator , the error is even in ± 500mP · s, so the test method of thickening zinc stearate is generally used to test a rotational viscometer , the viscosity and good  yellow iron oxide dispersion if just a few hours after the deviation is greater than the viscosity 500mP · s, as thickening 4 , oil absorption amount of oil and thickening think not the same concept , oil volume ratio of added amount in the same conditions, make the product viscosity, the viscosity does not exceed a period of time the error value ± 500mP · s. Oil Absorption test standards "DIN ENISO787-5-1995", usually in the PU coating on the oil absorption is not much demand because of the production will not cause much impact, paint manufacturers have high requirements on oil absorption , it may be some paint manufacturers to add more solvent , but want to reduce solvent evaporation , we must find some high oil absorption material added to it , and the amount of zinc stearate oil relative to other additives are higher oil absorption 5 additives , particle size is to indicate the size of the indicator particles of zinc stearate , are  titanium dioxide anatase generally used to measure the fineness . The easiest test is usually the result fineness is the fastest scraper fineness, usually in alkyd resin by adding a certain percentage of zinc powder dispersion , then add a little solvent viscosity good tune , and then use Fineness gauge testing, such test results will be higher than the actual fineness little too large , because the resin powder is wrapped in possession of a certain thickness , but as long as comparable and reproducible set standards in this test method can be to measure whether the excessive fineness . 6 , dispersed in the paint manufacturing process , there are many manufacturers dispersion problems mentioned . Under normal circumstances , zinc stearate dispersed in the paint is not a problem , but in the production of zinc stearate , there will be some indicators will cause the dispersion of certain effects, such as zinc stearate acid value is too high, the temperature is too high semi workers pressure occurs when the package is too severe zinc in the coating dispersion bad problem , but if the water is too high in zinc crystals also occur problems are considered dispersion good.

PVC heat stabilizer in the process is an indispensable additive

PVC heat stabilizers are indispensable in the process additives , as human beings living on their own health and environmental concerns surrounding gradual increase awareness of the world has promulgated a series of measures to limit the use of heavy metal heat stabilizers .
Outside the industry generally believe that understanding of PVC heat stabilizers environmental protection has become an tribasic lead sulphate  irreversible trend , PVC heat stabilizers in the process of environmental protection , research and development non-toxic, non-polluting , composite , and efficient heat stabilizers have been more widely application .
PVC resin having a self- catalytic release HCL, or to instability of the PVC resin produced by reflection from the addition polyalkylene structure , to prevent or reduce the decomposition of PVC resin . Generally used in the formulation of the thermal stabilizer features, functions and products required to consider. Here are a few people stabilizer features:
1 lead salt stabilizer is mainly used  vegetable stearic acid in hard products in . Lead salt stabilizer has good thermal stability , excellent electrical properties , low cost and so on. But its toxicity, easily contaminated products, can only produce opaque products. In recent years, large numbers of composite stabilizer , one-component stabilizer has the danger of being replaced . Composite stabilizer is characterized by specific and strong , pollution, processing enterprises, the advantages of simple ingredients . However, no uniform standard, so each of the composite stabilizer vary greatly.
2 barium cadmium -based stabilizers is white foaming agent  better performance of a heat stabilizers . Wider use of PVC plastic sheeting . Usually barium cadmium and zinc and organic phosphite antioxidant and use .
3 calcium zinc stabilizers can be used as non-toxic stabilizers used in food packaging and medical devices, pharmaceutical packaging, but its stability is relatively low education , a large amount of calcium -based stabilizers when transparency is poor , easy to spray cream. Calcium zinc stabilizers are usually used polyols and antioxidants to improve its performance, the country has recently been used in rigid pipe Ca-Zn compound stabilizer appears.
4 organotin heat stabilizers better performance for rigid PVC products with a better variety of transparent products , especially toxic octyl tin packaging products almost become indispensable stabilizer.

impact modifier and processing modifiers contrast between

Ideal resistance modifier should have the following properties:
① and modification of the substrate must have a good compatibility.
② modifier particle size, morphology medium a diameter of about 200nm is appropriate to protect the effect is a high impact strength .
③ modifier to lower the glass  iron oxide yellow transition temperature is preferred.
④ impact modifier preferably has slightly crosslinked to improve the reinforcing effect .
⑤ modifier processing properties of the resin without prejudice to its apparent performance and physical and mechanical properties without adverse effects.
⑥ requires non-toxic, non-polluting and affordable.
2 , the processing performance modifier
Processing modifier for plastic processing performance is poor and development of a class of additives that are added to improve the polymer in the molten resin flow , and a thermal stability, heat distortion resistance and surface gloss of the material products . Currently, the processing modifier is mainly to improve the melt viscosity of PVC , improved flowability and processability.
Processing modifier primarily polymer, the application is more acrylic copolymer , such as methyl methacrylate / acrylic acid copolymer system (MMA / FA system ) , methyl methacrylate / butyl methacrylate acrylate / ethyl acrylate / methyl methacrylate copolymer systems (MMA / BMA / EA / EMA system ) , methyl methacrylate / ethyl acrylate / acrylonitrile copolymer system (MMA / EA / AN system ), etc. The amount of resin added is usually from 3% to 8%.
( Two ) impact modifiers and processing modifier classification and species
1 , impact modifiers and species classification
① acrylonitrile - butadiene - styrene copolymer (ABS): ABS resin is a graft copolymer of polybutadiene latex is added to the styrene and acrylonitrile monomers copolymerized . Impact modifier for PVC, ABS has a good effect, the toughening effect, while the tensile strength and elongation decrease is small, the general amount of 10% to 20%. ABS  chromium oxide resin due to the presence of unsaturated structures , weather is poor, so products should not be long-term outdoor use . ABS resin is less than the compatibility with PVC, MBS, the product transparency is not as good MBS copolymer ; such as a transparent ABS and PVC blends can obtain a transparent products. When the ABS dosage of 20% to 30 %, the impact strength with excellent results.
② methyl methacrylate - butadiene - styrene copolymer (MBS): MBS is to polybutadiene or butadiene - styrene emulsion , methyl methacrylate graft copolymerized . Adding MBS resin can improve the impact toughness of PVC , polyvinyl chloride increase the transparency , but poor aging resistance of MBS , MBS higher rubber content , the higher the impact toughness . MBS added amount is generally 10% to 17 % is appropriate, more than 30 % of the brittle failure occurs .
③ chlorinated polyethylene (CPE): chlorinated polyethylene of high density polyethylene (HDPE) chlorination , chlorine content is generally 30% to 45% , depending on the resin component , the chlorine content , the molecular structure and morphology different , showing a rigid plastic from the rubber elastic body in different state changes. Molecular weight of 1,000,000 or more CPE is not only good impact resistance , and excellent weather resistance , ABS and MBS overcome the shortcomings of poor weather . In addition , CPE chlorine in a great effect on the size of the modified , low chlorine polyethylene oxide  content , its high crystallinity and poor toughness , high glass transition temperature , poor compatibility with PVC . Chlorine content is too high , CPE 's cohesion is stronger , but relatively poor dispersion . CPE in PVC dosage is generally 5% to 15%. CPE, cold resistance, chemical stability , flame resistance, oil resistance and electrical insulating properties are good .
④ ethylene - vinyl acetate copolymer (EVA): EVA used as modifiers of PVC , the vinyl acetate content should be more than 40 ¥ . EVA good weather resistance, modified PVC products can be used outdoors, but the transparency and tensile strength have declined. The addition of EVA is generally 5% ~ 10%, EVA as the modifier , also be used in the modified polyolefins , to improve weatherability , cold resistance .

Impact modifiers described in some detail

The reason why certain polymers show brittle at room temperature , which is mainly determined by the structure of the polymer itself . Polymer
The brittleness and its molecular main chain flexibility , the molecular chain of the more flexible , its brittleness is smaller , whereas the greater brittleness . All Movies
A flexible polymer chain affected by factors such as the main chain structure , a substituted group, the polymerization degree , crosslinking degree of the polymer can affect the brittle
Sex . To improve the toughness of Impact modifier for PVC  the material , the following three main ways : in
Rubber component introduced into the polymer structure , as in the bulk polymerization of styrene butadiene component may be introduced in
Preparation of high-impact polystyrene (
HIPS, which in situ in the reaction kettle modification techniques suitable for mass production . In
Introducing the polymer backbone monomers low glass transition temperature , such as bisphenol
A polycarbonate raw
Production . Through
After some modification method would have the effect of toughening complexes were blended with polymer materials ,
Thereby enhancing the impact properties of polymeric materials . Such complexes known as impact modifiers , these additives is mainly used polyvinyl chloride
Ene, polystyrene and other plastics . The modified method has the freedom and flexibility characteristics.
1.1
Mechanism of impact modifier
The impact modifier in the polymer research, although there are a large number of scholars have carried out a series of fruitful work , but to
Today there are some issues unresolved , so it is no unified theory. Different scholars have proposed a different interpretation ,
Summarized in the following: rubber absorbs energy theory , shear yield theory, theory of cracks , crazing shear zone management
On other . Due to the use of rubber or elastomer -modified impact of plastics material will also reduce the rigidity of the self
Since there has been replaced by vegetable stearic acid  rigid particles of rubber and elastomer toughened polymers ideas, and the corresponding emergence of non-
Rigid polymer particle toughening machine theory .
Rubber absorbs energy theory
Is stretched when the cross section is substantially found not shrink , thereby setting
Want to cavitation occurs inside the material and the density becomes small ( approximately 8% reduction )
Year. They think its elongation stress whitening phenomenon
Is generated within the material of the hole caused by the scattering of light . Therefore, the argument put forward : when the material strain , in its internal generated a lot of very fine cracks , then there must be a
Of rubber particles across the crack , thus preventing rapid crack
Rapid expansion , while the rubber particles in its consumption of energy during deformation due
, Thereby improving the toughness of the material . As shown, located
Rubber particles in a growth of the crack face , such that material by
To break the impact absorbed energy equal to the Brittle Fracture
We can add on to be broken rubber particles acting combined. While
Explained tensile yield , must liquid stabilizer  assume the formation of a large number of micro- cracks in the rubber particles absorb energy schematic
And each micro-cracks were blocked by rubber particles , micro-cracks are adjacent the substrate a thin layer of polystyrene are separated . Thus, a large tensile strain can be micro- cracks open, the rubber particles are
Elongated and polystyrene layers bend to achieve. Accordingly, they assume that the rubber particles have a "bridge " effect as well as particles having a high flexibility and good adhesion to the substrate with the premise . This theory is that it is the lack of attention to the rubber , while ignoring the polymer matrix . Toughened polystyrene and polyvinyl chloride is concerned, both in the fracture behavior of a significant difference , which is not easy to explain the theory of micro-cracks