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Catalyst and Auxiliary

The catalyst can change the reaction rate in the chemical reaction, and the composition and the quality of the catalyst can be kept constant after the reaction. The catalyst that accelerates the reaction is called the positive catalyst, slows down called Negative Catalyst or slow agent. It said catalyst is a positive catalyst for the general correction. This kind of catalyst in the industry, especially the organic chemical industry used more, and has great significance, Such as sulfuric acid prepared by contacting, ammonia, hydrolysis of the ester and polysaccharide, Oil Hydrogenation, etc. Commonly used catalysts are mainly metal, metal oxide and inorganic acid. If the catalyst is solid, the substance of the reaction is gas, to form a multi-phase catalytic reaction, this catalyst, sometimes called catalyst or contact agent. The catalyst is generally selective, it can only make a reaction or a certain type of reaction to speed up. But some reaction can be used for a variety of catalysts, such as the hydrogenation reaction can often be platinum, palladium, nickel, should be carefully chosen. In the catalytic reaction, the catalyst is often added cocatalyst known to enhance catalytic action of the catalyst. For example, iron is a catalyst in ammonia industry, adding a small amount of potassium and aluminum can enhance the catalytic effect of iron. The composition and weight of the catalyst and cocatalyst cannot change before and after the reaction. All of the above are inorganic catalysts. The enzyme is a protein, is very important organic catalyst.

There are many kinds of catalyst, catalyst and reaction system according to the phase of the classification, there are two types of homogeneous and heterogeneous catalysts. Heterogeneous catalysts most widely used, there are 3 kinds of gas, liquid and solid state, the variety and application of solid catalyst. The solid catalyst, which is made of metal (nickel, platinum, palladium, chromium, cobalt, titanium, vanadium, etc.) or metal oxide (copper oxide, vanadium pentoxide, lead oxide), is dispersed and deposited on the carrier in order to obtain a good dispersion effect and increase the specific surface area. The catalyst requires reliable activity, stability, selectivity, long working life, not easy to poisoning and over-burning, easy to regenerate. In order to improve the catalytic efficiency, the pure metal catalysts are made into alloy catalysts (such as nickel aluminium alloy) and composite catalysts (ZieglerNatta). The composite catalyst is composed of main catalyst and co-catalyst. In the new efficient catalysts also add other components. The production and development of high efficiency catalyst have promoted the development of polymer materials, and produced much polymer function and structure material ,which is new generation of high performance and high added value.

With the extensive application of catalyst and a number of new catalysts, we can make a lot of new chemical reactions to achieve industrialization, in order to provide an increasing number of chemical products; also can make some of the original chemical reaction conditions have been improved, in order to improve the production efficiency and product quality, make full use of resources. The important subject in the field of modern chemistry and chemical research is to select and develop more and better catalyst for the new generation. But the role of a catalyst is not beneficial to humans, such as combustion products of supersonic jet fuel as a catalyst can cause the stratosphere (10 to 50 km altitude) decomposition of ozone in the atmosphere, to the sun's ultraviolet absorption decreased, resulting in some areas of skin cancer patients increased. Is developing a new supersonic jet fuel, its combustion products will not become a catalyst,which will cause the ozone decomposition catalyst in the stratosphere.

Additives are added in the industrial and agricultural production, especially in the chemical production of some of the auxiliary chemicals, its role is to improve the production process, improve product quality and yield, or to give the product a unique application performance.

Additive are large class of important chemical in the production of auxiliary raw materials, they can give a special performance to product, improve use of finished products; and can accelerate the chemical reaction rate, improve product yield; they can save raw materials, improve processing efficiency. Additives are widely used in the chemical industry, especially organic synthesis, synthetic material processing and petroleum refining, pesticide, medicine, dye, paint and other industrial sectors. Additives can be divided into synthesized additives and processing additives. Synthetic additives are used in monomer synthesis and polymerization of a variety of auxiliary agents in resin, fiber, rubber, etc. They include catalysts, initiators, solvents, dispersants, emulsifiers, polymerization inhibitors, regulators, termination agents, etc. Processing aid refers to the auxiliary chemicals used in the manufacture of raw rubber, plastics processing, chemical fiber spinning and spinning process, including plasticizers, heat stabilizers, antioxidants, light stabilizers , flame retardants, blowing agents, lubricants, mold release agents, curing agents, accelerators, softeners, anti-scorching agents, surfactants, oils, fillers, etc. In these additives, many of them are dangerous chemicals, Such as benzoyl peroxide, azobisisobutyronitrile, hydrogen peroxide - ferrous blue, alkyl aluminum chloride, titanium and other initiators, catalysts are inflammable and explosive materials, should be required to "chemical Dangerous Goods Safety Management Regulations", for storage, transportation, operation and use.

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Structure Chemical Name CAS MF
Alkene-PEG-PLA(3K) Alkene-PEG-PLA(3K)
PLGA(10K)-PEG-Mal PLGA(10K)-PEG-Mal
Benzyl-PEG-OH Benzyl-PEG-OH
PLL-PEG-OH PLL-PEG-OH
PLGA(2K)-PEG-SC PLGA(2K)-PEG-SC
Phosphoric acid-PEG-COOH Phosphoric acid-PEG-COOH
ASP-PEG-ASP ASP-PEG-ASP
8-ArmPEG-(6Arm-Mal,2Arm-Biotin) 8-ArmPEG-(6Arm-Mal,2Arm-Biotin)
Cy3.5-PEG-Mal Cy3.5-PEG-Mal
mPEG-DMPE(ammonium salt) mPEG-DMPE(ammonium salt)
PLA(2K)-PEG-NH2 PLA(2K)-PEG-NH2
cRGD-PEG-NH2 cRGD-PEG-NH2
Tetraamminepalladium(II) dichloride Tetraamminepalladium(II) dichloride 13815-17-3 ClH8N4Pd+
Azido-PEG24-NHS ester Azido-PEG24-NHS ester 2375600-46-5 C55H104N4O28
TETRAAMMINEPALLADIUM(II) TETRACHLOROPALLADATE(II) TETRAAMMINEPALLADIUM(II) TETRACHLOROPALLADATE(II) 13820-44-5 Cl4H8N4Pd2
Metal deactivator T553 Metal deactivator T553
DMPE PEG NHS DMPE PEG NHS
Monoethoxylsilane-PEG-COOH Monoethoxylsilane-PEG-COOH
POTASSIUM TETRABROMOPALLADATE(II) POTASSIUM TETRABROMOPALLADATE(II) 13826-93-2 Br4H4KPd-
Diazepam SE Diazepam SE
NA NA
Formaldehyde synthesis catalyst Formaldehyde synthesis catalyst
Industrial slurry bed nitro-hydrogenation catalyst Industrial slurry bed nitro-hydrogenation catalyst
Industrial butanol and octanol liquid-phase hydrogenation catalyst Industrial butanol and octanol liquid-phase hydrogenation catalyst
para polyphenylene para polyphenylene
AgiSyn 717 AgiSyn 717
HO-PEG16-OH HO-PEG16-OH 4669-05-0 C32H66O16
Alkyne-PEG-Mal Alkyne-PEG-Mal
mPEG-SS-NHS mPEG-SS-NHS
Retinoic acid PEG azide Retinoic acid PEG azide
Cysteine PEG Cysteine Cysteine PEG Cysteine
Retinoic acid PEG Maleimide Retinoic acid PEG Maleimide
Fmoc-NH-PEG12-CH2CH2COOH Fmoc-NH-PEG12-CH2CH2COOH 1952360-91-6 C42H65NO16
Dopamine-PEG-Dopamine Dopamine-PEG-Dopamine
8-arm-PEG-OPSS 8-arm-PEG-OPSS
FA-PEG-OH FA-PEG-OH
mPEG-FITC mPEG-FITC
OPSS-PEG-MAL OPSS-PEG-MAL
DSPE-PEG(5000) DBCO DSPE-PEG(5000) DBCO 2052955-83-4
POLY(VINYLACETATE PHTHALATE) POLY(VINYLACETATE PHTHALATE) 53237-50-6 C12H14O7
PLGA-COOH PLGA-COOH
8-ArmPEG-(7Arm-COOH,1ARrm-NH2) 8-ArmPEG-(7Arm-COOH,1ARrm-NH2)
ACA-PEG-NH-Mal ACA-PEG-NH-Mal
Benzyl-PEG40-OH Benzyl-PEG40-OH
CLS-PEG-NBD CLS-PEG-NBD
COOH-PEG-NH2.HCl COOH-PEG-NH2.HCl
DMPE-PEG-SC DMPE-PEG-SC
DPPE-PEG-SC DPPE-PEG-SC
FA-PEG4-Alkyne FA-PEG4-Alkyne
mPEG-Anilin mPEG-Anilin
N3-PEG-PAA(1.8K)-DA N3-PEG-PAA(1.8K)-DA
PLGA(12K)-PEG-NH2 PLGA(12K)-PEG-NH2
PLGA(2K)-PEG-COOH PLGA(2K)-PEG-COOH
STA-PEG-SC STA-PEG-SC
URANIUM URANIUM 7440-61-1 U
SG-PEG-SG SG-PEG-SG
4-arm-PEG-OPSS 4-arm-PEG-OPSS
Alkyne-PEG-FITC Alkyne-PEG-FITC
mPEG-PLGA mPEG-PLGA
Acetylthio-PEG-Mal Acetylthio-PEG-Mal
AC-PEG-SS-PEG-AC AC-PEG-SS-PEG-AC
Biotin-PEG-CHO Biotin-PEG-CHO
CLS-PEG-Biotin CLS-PEG-Biotin
Cy5-PEG-COOH Cy5-PEG-COOH
DA-PEG-NH2 DA-PEG-NH2 1383691-49-3 (C2H4O)nC12H18N2O4
FITC-PEG-Progestrone FITC-PEG-Progestrone
mPEG-CLS mPEG-CLS
NH2-PEG-GAA NH2-PEG-GAA
Palmitic acid-PEG-COOH Palmitic acid-PEG-COOH
Phosphoric acid-PEG-N3 Phosphoric acid-PEG-N3
PLGA(50:50)(8K)-PEG-Mal PLGA(50:50)(8K)-PEG-Mal
VD-PEG-Mal VD-PEG-Mal
4-(4-Pyridyl)Benzoic Acid 4-(4-Pyridyl)Benzoic Acid 2163772-19-6 C42H45N7O8
2,2,6,6-Tetramethyl-4-piperidinyl stearate 2,2,6,6-Tetramethyl-4-piperidinyl stearate 167078-06-0 C27H53NO2
2-Hydroxy-4-methoxybenzophenone-5-sodium sulfonate 2-Hydroxy-4-methoxybenzophenone-5-sodium sulfonate 6628-37-1 C14H13NaO6S
Pentaerythritol glycidyl ether Pentaerythritol glycidyl ether 3126-63-4 C17H28O8
dipotassium tetrakis(thiocyanato-S)palladate(2-) dipotassium tetrakis(thiocyanato-S)palladate(2-) 14516-47-3 C4K2N4PdS4
WETTING AGENT FOR PRINTING INKS WETTING AGENT FOR PRINTING INKS
OLETH-2 PHOSPHATE OLETH-2 PHOSPHATE 39464-69-2 (C2H4O)nC18H36O.xH3O4P
PEG derivatives PEG derivatives
Palladium carbon catalyst 5% Palladium carbon catalyst 5%
Pyralene Pyralene
UV Absorber 3030 UV Absorber 3030 178671-58-4 C69H48N4O8
Cellulose diacetate Cellulose diacetate 9035-69-2 C2H4O2
Teflon micropowder lubricant Teflon micropowder lubricant
Copper on Zirconium Phosphate Copper on Zirconium Phosphate
Tin Zinc Pb Copper Alloy Powder Tin Zinc Pb Copper Alloy Powder
MONO-ANDDIGLYCERIDESOFFATTYACIDS MONO-ANDDIGLYCERIDESOFFATTYACIDS
Polyethylenglykoldiallylether Polyethylenglykoldiallylether 59788-01-1
Molecular Sieve SSZ-39 Molecular Sieve SSZ-39
9,9-Bis[4-(2-acryloyloxyethyloxy)phenyl]fluorene 9,9-Bis[4-(2-acryloyloxyethyloxy)phenyl]fluorene 161182-73-6 C35H30O6
Light stabilizer 3529 Light stabilizer 3529 193098-40-7 (C33H60N80)n
Hexafluoropropylene dimer/perfluoro (4-methyl-2-pentene) HFO-1336mzz Hexafluoropropylene dimer/perfluoro (4-methyl-2-pentene) HFO-1336mzz
PCL Microspheres PCL Microspheres
Iodoacetyl-PEG-Mal Iodoacetyl-PEG-Mal
8-Arm PEG-SA 8-Arm PEG-SA
DSPE-PEG-COOH DSPE-PEG-COOH C48H90NO14P
CY5.5-PEG-SH CY5.5-PEG-SH
DIHYDROGEN DI-MU-CHLORODICHLOROBIS(DI-T-BUTYLPHOSPHINITO-KP)DIPALLADATE(2-) DIHYDROGEN DI-MU-CHLORODICHLOROBIS(DI-T-BUTYLPHOSPHINITO-KP)DIPALLADATE(2-) 386706-32-7 C16H39Cl4O2P2Pd2-
Tetrakis(tri-o-tolylphosphine)palladium(0) Tetrakis(tri-o-tolylphosphine)palladium(0) 175164-86-0 C84H84P4Pd
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