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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
mPEG-NH-CHO mPEG-NH-CHO
NH2-PEG-PA NH2-PEG-PA
MTX-PEG-NH2 MTX-PEG-NH2
PAA(2K)-PEG-NH2 PAA(2K)-PEG-NH2
NH2-PEG-Mannose NH2-PEG-Mannose
SH-PEG7-NH2.HCl SH-PEG7-NH2.HCl
Ruthenium red test solution Ruthenium red staining solution Colorant Ruthenium red test solution Ruthenium red staining solution Colorant
2,5-bis(tert-dodecyldithio)-1,3,4-thiadiazole 2,5-bis(tert-dodecyldithio)-1,3,4-thiadiazole 59656-20-1 C26H50N2S5
Metal ruthenium powder Metal ruthenium powder
O-(2-Aminoethyl)-O'-[2-(Boc-amino)ethyl]polyethylene glycol 3000 O-(2-Aminoethyl)-O'-[2-(Boc-amino)ethyl]polyethylene glycol 3000 198227-38-2 C29H60N2O13
(η(5):η(1)-C13H8SiMe2N(t)Bu)ZrCl2 (η(5):η(1)-C13H8SiMe2N(t)Bu)ZrCl2 145519-50-2 C19H23Cl2NSiZr
Palladium, [μ-[1,1'-(1,4-butanediyl)bis[1,1-bis(1,1-dimethylethyl)phosphine-κP]]]dichlorobis[(1,2,3-η)-1-phenyl-2-propen-1-yl]di- Palladium, [μ-[1,1'-(1,4-butanediyl)bis[1,1-bis(1,1-dimethylethyl)phosphine-κP]]]dichlorobis[(1,2,3-η)-1-phenyl-2-propen-1-yl]di- 2756973-32-5 C38H58Cl2P2Pd2
2-Hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone 2-Hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone 106797-53-9 C12H16O4
Propanoic acid, 2-?hydroxy-?, polymer with 2-?hydroxyacetic acid Propanoic acid, 2-?hydroxy-?, polymer with 2-?hydroxyacetic acid 34346-01-5 C5H10O6
Α-azido-Ω-mercapto polyethylene glycol Α-azido-Ω-mercapto polyethylene glycol
mPEG-SA(mPEG-Succinic acid) mPEG-SA(mPEG-Succinic acid)
mPEG-VS(mPEG-Vinyl sulfone) mPEG-VS(mPEG-Vinyl sulfone)
Iodoacetyl-PEG-Biotin Iodoacetyl-PEG-Biotin
Thalidomide-O-PEG4-amine Thalidomide-O-PEG4-amine 2401832-00-4 C23H31N3O9
Thalidomide-O-PEG4-Propargyl Thalidomide-O-PEG4-Propargyl 2098799-77-8 C24H28N2O9
Fmoc-Lys-PEG8-OH Fmoc-Lys-PEG8-OH
Poly(dipropyleneglycol)phenyl phosphite Poly(dipropyleneglycol)phenyl phosphite 80584-86-7 C102H134O31P8
Vinyl resin Vinyl resin
Alcohols, C12-14, ethoxylated propoxylated Alcohols, C12-14, ethoxylated propoxylated 68439-51-0
[DSPE-PEG-MAL] α-Maleimidyl-ω-distearoyl-sn-glycero-3-phosphoethanolamino poly(ethylene glycol) [DSPE-PEG-MAL] α-Maleimidyl-ω-distearoyl-sn-glycero-3-phosphoethanolamino poly(ethylene glycol)
Teflon micropowder rubber and plastic Teflon micropowder rubber and plastic
PVM/MA PVM/MA 1644545-52-7 C14H13ClF6N6
BIS(2-METHYLALLYL)PALLADIUM CHLORIDE DIMER BIS(2-METHYLALLYL)PALLADIUM CHLORIDE DIMER 12081-18-4 C16H28Cl2Pd2
CARBOPOL ETD 2020 CARBOPOL ETD 2020 176429-87-1
DSPE-PEG-NHS DSPE-PEG-NHS 1445723-73-8 C49H89N2O15P
Poly(dimethylamine-co-epichlorohydrin-co-ethylenediamine) Poly(dimethylamine-co-epichlorohydrin-co-ethylenediamine) 42751-79-1 C7H20ClN3O
zirconium carbide zirconium carbide 12020-14-3 ErFeH2O
	1,3-Dimethyl-1,3-diphenylurea 1,3-Dimethyl-1,3-diphenylurea 611-92-7 C15H16N2O
5-BENZOXAZOLOL, 2-METHYL- 5-BENZOXAZOLOL, 2-METHYL- 23997-94-6 C8H7NO2
Chloro[1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene]gold(I) Chloro[1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene]gold(I) 852445-81-9 C21H24AuClN2
Di-chlorobis[(1,2,3-)-1-phenyl-2-propenyl]dipalladium(II) Di-chlorobis[(1,2,3-)-1-phenyl-2-propenyl]dipalladium(II) 12131-44-1 C18H12Cl2Pd2
α-Azido-ω-MaleiMidyl poly(ethylene glycol) α-Azido-ω-MaleiMidyl poly(ethylene glycol)
UV-791 UV-791
DibroMo(1,5-cyclooctadiene)palladiuM(II) DibroMo(1,5-cyclooctadiene)palladiuM(II) 12145-47-0 C8H12Br2Pd
acrylate-PEG-acrylate acrylate-PEG-acrylate
Thio-PEG12-acid Thio-PEG12-acid 1032347-93-5 C27H54O14S
UV absorber UV-9 UV absorber UV-9 131-57-7 C14H12O3
DSPE-PEG-Silane DSPE-PEG-Silane
FITC-PEG-NHS FITC-PEG-NHS
S-acetyl-PEG4-Propargyl S-acetyl-PEG4-Propargyl 1422540-88-2 C13H22O5S
Di-μ-iodobis(tri-t-butylphosphino)dipalladium(I) Di-μ-iodobis(tri-t-butylphosphino)dipalladium(I) 166445-62-1 C24H56I2P2Pd2
ALPHA,OMEGA-BIS(PROPIONIC ACID) DODECAE(ETHYLENE GLYCOL) ALPHA,OMEGA-BIS(PROPIONIC ACID) DODECAE(ETHYLENE GLYCOL) 892155-64-5 C30H58O17
POTASSIUM TETRANITROPALLADATE(II) POTASSIUM TETRANITROPALLADATE(II) 13844-89-8 K2N4O8Pd
Tetrazine PEG Maleimide Tetrazine PEG Maleimide
Lysine PEG Lysine Lysine PEG Lysine
DMPE PEG NBD DMPE PEG NBD
Monoethoxylsilane-PEG-Biotin Monoethoxylsilane-PEG-Biotin
CHO-PEG12-COOH CHO-PEG12-COOH
Chloro{1,3-bis[2,6-di-i-propylphenyl]-4,5-dihydroimidazol-2-ylidene}gold(I) Chloro{1,3-bis[2,6-di-i-propylphenyl]-4,5-dihydroimidazol-2-ylidene}gold(I) 852445-84-2 C27H38AuClN2
Br-PEG-OH Br-PEG-OH
Silane-PEG-SH Silane-PEG-SH
TRANS-DIBROMOBIS(TRIPHENYLPHOSPHINE)- TRANS-DIBROMOBIS(TRIPHENYLPHOSPHINE)- 22180-53-6 C36H30Br2P2Pd
2(BIS(2 4DI-T-BU-PHENOXY)PHOSPHINOOXY)3 2(BIS(2 4DI-T-BU-PHENOXY)PHOSPHINOOXY)3 217189-40-7 C84H126Cl2O6P2Pd2
No. 3 extreme pressure lithium grease No. 3 extreme pressure lithium grease
No. 68 industrial white oil No. 68 industrial white oil
TCO-PEG3-FITC TCO-PEG3-FITC
4-ArmPEG-(2OH-2COOH) 4-ArmPEG-(2OH-2COOH)
COOH-PEG-Tretinoin COOH-PEG-Tretinoin
Monoethoxylsilane-PEG-SC Monoethoxylsilane-PEG-SC
Alkyne-PEG-Silane Alkyne-PEG-Silane
DBCO-PEG-SVA DBCO-PEG-SVA
PLGA(5K)-PEG-SH PLGA(5K)-PEG-SH
8-ArmPEG-(7Arm-OCH3,1ARrm-SH) 8-ArmPEG-(7Arm-OCH3,1ARrm-SH)
NH2-PEG-Retinoic acid NH2-PEG-Retinoic acid
COOH-PEG-N+Me3 COOH-PEG-N+Me3
Palmitic acid-PEG-NH2 Palmitic acid-PEG-NH2
tetraethyl 2,2'-(1,4-phenylenedimethylidyne)bismalonate tetraethyl 2,2'-(1,4-phenylenedimethylidyne)bismalonate 6337-43-5 C22H26O8
m-PEG-Aminooxy m-PEG-Aminooxy
m-PEG-CH2COOH m-PEG-CH2COOH
Resin acids and Rosin acids, maleated, esters with glycerol Resin acids and Rosin acids, maleated, esters with glycerol 94581-16-5
SH-PEG4-NH2·HCl SH-PEG4-NH2·HCl
Bis(2,26,6Tetramethylheptanedionato)palladium(II) Bis(2,26,6Tetramethylheptanedionato)palladium(II) 15214-66-1 C22H38O4Pd
Photoinitiator Photoinitiator
Platinum on activated carbon Platinum on activated carbon
GPhos Pd G3 GPhos Pd G3 2489525-82-6
Bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate Bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate 41556-26-7 C30H56N2O4
NHS-PEG-MAL NHS-PEG-MAL
teflon wax teflon wax
alpha,omega-Di-succinimidyl ester poly(ethylene glycol) (PEG-MW 10.000 Dalton) alpha,omega-Di-succinimidyl ester poly(ethylene glycol) (PEG-MW 10.000 Dalton) C20H26N4O11
O-(2-CARBOXYETHYL)POLYETHYLENE GLYCOL O-(2-CARBOXYETHYL)POLYETHYLENE GLYCOL 117786-94-4 H(OCH2CH2)nCH2CH2COOH
Antioxidant T502 Antioxidant T502
O-[2-(Biotinyl-amino)ethyl]-Oμ-(2-carboxyethyl)polyethylene  glycol  3000 O-[2-(Biotinyl-amino)ethyl]-Oμ-(2-carboxyethyl)polyethylene glycol 3000 948595-11-7 (C2H4O)nC15H25N3O5S
Carboxymethylcellulose sodium salt Carboxymethylcellulose sodium salt 9085-26-1 C8H16NaO8
Polyethylene glycol-G-thiol Polyethylene glycol-G-thiol
Glutamic Acid PEG Glutamic Acid Glutamic Acid PEG Glutamic Acid
Vitamin D PEG NH2 Vitamin D PEG NH2
mPEG Tetrazine mPEG Tetrazine
Biotin-PEG3-CH2COOH Biotin-PEG3-CH2COOH 1189560-96-0 C18H31N3O7S
4-Methylmorpholine N-oxide monohydrate 4-Methylmorpholine N-oxide monohydrate 70187-32-5 C5H11NO2
Tinuvin-1130 Tinuvin-1130 104810-47-1 C20H23N3O3
Bis(tert-butyldioxyisopropyl)benzene Bis(tert-butyldioxyisopropyl)benzene 25155-25-3 C20H34O4
2’,4’-Di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate 2’,4’-Di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate 4221-80-1 C29H42O3
SAS-PEG-SAS SAS-PEG-SAS
Boc-NH-PEG-Mal Boc-NH-PEG-Mal
FITC-PEG-N3 FITC-PEG-N3
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