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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
SH-PEG-SS SH-PEG-SS
CHO-PEG-SCM CHO-PEG-SCM
COOH-PEG-HZ COOH-PEG-HZ
Biotin-PEG-Tretinoin Biotin-PEG-Tretinoin
BOC-NH-PEG-SG BOC-NH-PEG-SG
MTX-PEG-Mal MTX-PEG-Mal
c(RGDyk)-PEG-SH c(RGDyk)-PEG-SH
HZ-PEG-N3 HZ-PEG-N3
Cy3.5-PEG-SH Cy3.5-PEG-SH
NH2.HCl-PEG-NH2.HCl NH2.HCl-PEG-NH2.HCl
Diethoxylsilane-PEG-NH2 Diethoxylsilane-PEG-NH2
DSPE(Sodium salt)-PEG-OH DSPE(Sodium salt)-PEG-OH
Teflon micropowder lubricant Teflon micropowder lubricant
Light stabilizer 3529 Light stabilizer 3529 193098-40-7 (C33H60N80)n
Polyethylenglykoldiallylether Polyethylenglykoldiallylether 59788-01-1
Molecular Sieve SSZ-39 Molecular Sieve SSZ-39
Tin Zinc Pb Copper Alloy Powder Tin Zinc Pb Copper Alloy Powder
Cellulose diacetate Cellulose diacetate 9035-69-2 C2H4O2
(R,R)-(-)-2,3-Bis(t-butylmethylphosphino)quinoxaline (R,R)-(-)-2,3-Bis(t-butylmethylphosphino)quinoxaline 866081-62-1 C18H28N2P2
Tetrazine PEG Biotin Tetrazine PEG Biotin
Estrogen PEG Fluorescein Estrogen PEG Fluorescein
Retinoic acid PEG Biotin Retinoic acid PEG Biotin
Diethoxylsilane-PEG-Biotin Diethoxylsilane-PEG-Biotin
Retinoic acid PEG acid Retinoic acid PEG acid
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
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
FITC-PEG-Progestrone FITC-PEG-Progestrone
Boron trifluoride acetonitrile complex Boron trifluoride acetonitrile complex 420-16-6 C2H3BF3N
Palladium carbon catalyst 5% Palladium carbon catalyst 5%
Pyralene Pyralene
UV Absorber 3030 UV Absorber 3030 178671-58-4 C69H48N4O8
POTASSIUM TETRABROMOPALLADATE(II) POTASSIUM TETRABROMOPALLADATE(II) 13826-93-2 Br4H4KPd-
Alkyne-PEG-Mal Alkyne-PEG-Mal
TETRAAMMINEPALLADIUM(II) TETRACHLOROPALLADATE(II) TETRAAMMINEPALLADIUM(II) TETRACHLOROPALLADATE(II) 13820-44-5 Cl4H8N4Pd2
Metal deactivator T553 Metal deactivator T553
mPEG-SS-NHS mPEG-SS-NHS
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
Tetrakis(tri-o-tolylphosphine)palladium(0) Tetrakis(tri-o-tolylphosphine)palladium(0) 175164-86-0 C84H84P4Pd
DMPE PEG NHS DMPE PEG NHS
Monoethoxylsilane-PEG-COOH Monoethoxylsilane-PEG-COOH
Retinoic acid PEG azide Retinoic acid PEG azide
Cysteine PEG Cysteine Cysteine PEG Cysteine
Retinoic acid PEG Maleimide Retinoic acid PEG Maleimide
rac-Ethylenebis(4,5,6,7-tetrahydro-1-indenyl)]zirconium dichloride rac-Ethylenebis(4,5,6,7-tetrahydro-1-indenyl)]zirconium dichloride 100163-29-9 C20H24Cl2Zr10*
4,4'-Butylidenebis(6-tert-butyl-3-methylphenol) 4,4'-Butylidenebis(6-tert-butyl-3-methylphenol) 85-60-9 C26H38O2
UV Absorber 326 UV Absorber 326 3896-11-5 C17H18ClN3O
α-ForMyl-ω-carboxyl poly(ethylene glycol) α-ForMyl-ω-carboxyl poly(ethylene glycol)
[(R)-(+)-2,2′-Bis(di-p-tolylphosphino)-1,1′-binaphthyl]palladiuM(II) chloride [(R)-(+)-2,2′-Bis(di-p-tolylphosphino)-1,1′-binaphthyl]palladiuM(II) chloride 191654-69-0 C48H42Cl2P2Pd
 	Zinc Acrylate Self-polishing Resin Zinc Acrylate Self-polishing Resin
Folic acid PEG DSPE Folic acid PEG DSPE 1236288-25-7
DSPE-PEG-Mal DSPE-PEG-Mal 474922-22-0
mPEG-COOH mPEG-COOH
Ethyl 4-[[(methylphenylamino)methylene]amino]benzoate Ethyl 4-[[(methylphenylamino)methylene]amino]benzoate 57834-33-0 C17H18N2O2
ALKYNE-PEG-CHO ALKYNE-PEG-CHO
Polyethylene glycol-G-isocyanate Polyethylene glycol-G-isocyanate
Thiol-PEG3-acid Thiol-PEG3-acid 1347750-82-6 C9H18O5S
mPEG-NPC(mPEG-4-nitrophenyl carbonate) mPEG-NPC(mPEG-4-nitrophenyl carbonate)
SA-PEG-SA(Succinic Acid-PEG-Succinic Acid) SA-PEG-SA(Succinic Acid-PEG-Succinic Acid)
Acrylamide-PEG-Acrylamide Acrylamide-PEG-Acrylamide
ACA-PEG-OH ACA-PEG-OH
8-Arm PEG-GA 8-Arm PEG-GA
DSPE-PEG-ACA DSPE-PEG-ACA C47H89N2O11P
SPhos Pd G4 SPhos Pd G4
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
Neutral palladium on carbon catalyst Neutral palladium on carbon catalyst
No. 0 general purpose lithium base grease No. 0 general purpose lithium base grease
2,3,4,5-TETRAMETHYLCYCLOPENTADIENEDIMETHYLSILYL-TERT-BUTYLAMIDO TITANIUM DICHLORIDE 2,3,4,5-TETRAMETHYLCYCLOPENTADIENEDIMETHYLSILYL-TERT-BUTYLAMIDO TITANIUM DICHLORIDE 135072-61-6 C15H27Cl2NSiTi
HEXAFLUOROPROPYLENE OXIDE DIMER HEXAFLUOROPROPYLENE OXIDE DIMER C6F12O2
Dichloro[η(5):η(1)-N-dimethyl(tetramethylcyclopentadienyl)silyl(tert-butyl)amido]titanium Dichloro[η(5):η(1)-N-dimethyl(tetramethylcyclopentadienyl)silyl(tert-butyl)amido]titanium 162763-85-1 C15H27Cl2NSiTi
Fmoc-Lys-PEG4-OH Fmoc-Lys-PEG4-OH
Fmoc-NH-PEG-SG Fmoc-NH-PEG-SG
C18H37-PEG-Sulfate C18H37-PEG-Sulfate
S-Acetyl-PEG-OH S-Acetyl-PEG-OH
PLGA(17K)-PEG-COOH PLGA(17K)-PEG-COOH
CY5-PEG-PCL(2K) CY5-PEG-PCL(2K)
Monoethoxylsilane-PEG-NH2 Monoethoxylsilane-PEG-NH2
DLPE-PEG-NH2 DLPE-PEG-NH2
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
OLETH-2 PHOSPHATE OLETH-2 PHOSPHATE 39464-69-2 (C18H36O).(C2H4O)n.x(H3PO4)
PEG derivatives PEG derivatives
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