Anti-plasticizing Effect Of Plasticizers
Plasticizer is one of the most productive auxiliaries in plastic additives, and the main products are DOP, bop, DIBP and DIDP, and China has become the largest producer and consumer Plasticizer in Asia. Reply to "auxiliaries" for more information
The concept of plasticizers
Any material that can reduce the melt temperature of the resin and improve the fluidity of the resin in the molten state and the softness of the product are called plasticizers. When Plasticizer is added to polymer material, it can reduce its melt viscosity, Plasticizer glass transition temperature and elastic touch without changing its basic chemical properties, which can improve its processability and improve the softness and tensile properties of the product.
The plasticizing principle of plasticizer
1. Polymer materials in the role of resistance to plasticizing factors
1 intermolecular force
The polymer materials composed of high molecular chains with higher spatial rules can be localized crystals under suitable conditions, Plasticizer and the crystallization zone is more stable than the amorphous region, the free space is smaller, more difficult to plasticizing, in short, to make the polymer material plasticizing, it must weaken its intermolecular force and destroy the crystallization zone. Reply to "auxiliaries" for more information
2. Plasticizer Principle of plasticizing
With regard to the principle of plasticizers, there are many theoretical viewpoints in the industry, such as: Lubrication theory, Gel theory and free volume theory, the most commonly accepted formulation is: Polymer material plasticized, is due to the material in the polymer molecule chain aggregation effect is weakened. That is, the plasticizer molecule is inserted between the polymer molecular chain, Plasticizer which weakens the force of the polymer molecule chain, the result increases the mobility of the polymer molecule chain, reduces the crystallinity of the polymer, and thus increases the plasticity of the polymer.
. Plasticizer's anti-plasticizing effect
When the dosage of plasticizer is reduced to a certain degree, it will result in the increase of the hardness of polymer material, the decrease of elongation rate and the decrease of impact strength. Plasticizer It is generally believed that the reason of the anti plasticizing effect is that a small amount of plasticizer makes the polymer chain move easily and promotes the orientation and crystallization of the amorphous region.
Classification of Plasticizers
1. The introduction can be divided into: internal plasticizers and external plasticizers
External Plasticizers--to add the way to introduce polymer materials plasticizer, can also be called "added Plasticizer", its outstanding advantages are easy to adjust the amount of flexibility and control of the degree of plasticizing, is commonly used plasticizers, usually referred to as plasticizers refers to external plasticizers. Reply to "auxiliaries" for more information
2. According to compatibility can be divided into main plasticizer and auxiliary plasticizers
The main plasticizer--and the basic polymer material (resin, rubber) compatibility is good, its molecules can not only enter the polymer material of the amorphous zone, Plasticizer but also can be inserted into the crystallization zone, also known as "solvent-based plasticizer", can be used alone. Auxiliary Plasticizer--the compatibility with the basic polymer material (resin, rubber) is poor, its molecule can only enter the amorphous region of the polymer material, but cannot insert the crystallization area, can only use with the main plasticizer together, cannot use alone.
3. According to applicability can be divided into universal, high-performance and special plasticizers
General-Purpose Plasticizer (GP)---cost-effective, good performance balance and thus a strong applicability of plasticizers. Phthalate esters are typical plasticizers. High-Performance plasticizer (PP)--a plasticizer that provides some particular excellent performance, including:
① Strong solvent Type (PP-SS) Plasticizer: can provide a particularly strong plasticizing properties, commonly used mainly in the polar strong special phthalate esters, Plasticizer high aromatic ring content of non-phthalic acid ester, such as benzoic acid ester, phosphoric acid, such as toluene.
② low-temperature-resistant (PP-LT) Plasticizer: can provide particularly good resistance to isothermal properties, also known as cold plasticizer, commonly used mainly aliphatic two-acid ester.
③ low Volatile (PP-LV) Plasticizer: With a particularly low volatility, also known as heat-resistant plasticizers, commonly used mainly in the benzene tri-acid ester and polyester.
Special Plasticizers-plasticizers that provide some/some special properties, including:
① Low diffusion type (SP-LD) Plasticizer: With a particularly low diffusivity, also known as durability plasticizer, commonly used mainly in polyester.
② Heat-stabilized (Sp-stab) Plasticizer: The function of PVC-assisted heat stabilizer, commonly used in epoxy compounds.
③ Flame Retardant Type (SP-FR) Plasticizer: Both flame retardant function, Plasticizer commonly used mainly phosphate ester and halogenated hydrocarbons.
4. According to the chemical structure can be divided into
① phthalate esters: including adjacent, pair, and phthalic acid ester.
② aliphatic two acid ester: including Hexyl hexanoate, nonylphenol ester, decyl acid ester, etc.
③ phenyl acid ester: including benzene phthalate ester and benzene ester.
④ polyol esters: The lower fatty acid esters and benzoic acid esters of four yuan alcohols, such as glycol, two yuan alcohol, propanol, etc.
⑤ citrate esters: including citric acid fatty alcohols ester and acetyl citrate fatty alcohol ester.
⑥ phosphate ester: Includes phosphoric acid aliphatic alcohol ester, phenol phosphate ester, Plasticizer phosphoric acid mixed ester and chlorinated phosphate ester.
⑦ Polyester: Two-yuan acid and two-yuan alcohol polycondensation.
⑧ epoxy compounds: including epoxy oil, epoxy fatty acid ester and so on.
⑨ other: such as chlorinated hydrocarbons, benzoic acid, etc.
Requirements for Plasticizers
1. Plasticizer effect is better
2. Plasticizer and resin compatibility, easy to disperse in the resin, not easily volatile, no dialysis, no extraction, not by swelling or chemical substances occur physical or chemical effects
3. Good durability, long-term preservation in resin
4. With other auxiliaries in the processing or use conditions do not occur
5. Heat resistance to light cold resistance, Plasticizer electrical insulation is better, not easy to burn, low toxicity or non-toxic.