Aminopropyl siloxane

Structural Formula Poly[N-(2-aminotethyl)-3-aminopropyl]siloxane-coated non-stoichiometric magnetite... 

Spacer bonded propanediol Si-(CH2)30CH2CH(0H)CH20H Used in NPC and RPC but more useful for NPC because of low retention in RPC. Reasonable retention of polar compounds by hydrogen bond and dipole-type interactions in NPC. More hydrogen-bond acidic and less hydrogen-bond basic then aminopropyl-siloxane-bonded layers in NPC. More retentive than amino-propylsiloxane-bonded layers in RPC. Similar retention to short chain alkylsiloxane-bonded layers but different selectivity for hydrogen- bonding compounds ... 

As it was mentioned above, as far back as 1966 a method was advanced for producing aminoorganosUica gel by hydrolysis of 3-aminopropyltriethoxysilane (APTES) [or of its mixrnres with tetraethoxysilane (TEOS)] in an alkali medium [11]. The procedure for producing poly (3-aminopropyl)siloxane (PAPS) xerogel involved interaction of a mixrnre TEOS/APTES (42 15 cm ) in 50 cm of methanol in the presence of 10 cm of a 0.5 M solution of NaOH. The obtained gel was washed for 7 days up to the neutral reaction of washing waters and dried at 120°C up to constant sample weight. The adsorptive capacity of the sorbent with respect to methacrylic acid was equal to 1.6 cm /g. 

Amphiphilic polysiloxanes have been recently obtained by reacting a water-soluble poly(3-aminopropyl)siloxane with fatty acid chlorides to attach hydrophobic moieties and subsequently with gluconolactone which provided the hydrophilic groups. The regularity of the nanoaggregates in water formed from the amphiphilic polysiloxanes was relatively controlled by the chain lengths and fimctionalities of the hydrophobic parts [90],... 

The complexes of Co(II) with salen and salophen were prepared according to [9,10]. The poly(3-aminopropyl) siloxane matrix (SAP) was obtained by the procedure [11] with some small modifications of this method [12]. Tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTES) (Aldrich) were used without previous pimfication. 

Figure 2. Schematic representation of the modification route. Surface Ti water-vapor—plasma-pretreated titanium. Surface A poljr(3-aminopropyl)siloxane pendant surface. Surface M maleimide-modified surfaces with different alkyl chains. Surface P peptide- or L-cysteine-modified surfaces. H-SR L-cysteine, RGDC, and GRGDSPC.

In siunmary, a three-step reaction procedure was employed to attach RGD-containing peptides onto a titanium surface. First, water-vapor-plasma-pretreated titanium surfaces were silanized with (3-aminopropyl)-triethoxysilane in dry toluene, resulting in a multilayer film of poly(3-aminopropyl)siloxane. Second, the free primary amino groups were linked to one of the three hetero-cross-hnkers AI-succinimidyl-6-maleimidylhex-anoate, iV-succinimidyl-3-maleimidylpropionate, and N-... 

In this study polymer immobilization involved the reaction of carboxylic acid polymers (CAPs) with APS (3-aminopropyl siloxane) functionalized glass beads (Scheme 1). The polymers, PAA and PMA reacted with the active APS amine groups to form salts. 

Bazylak, G. and Aboul-Enein, H.Y., Enantioseparation in series of beta-blockers by normal-phase planar chromatography systems with bonded aminopropyl-siloxane silica layer and chiral counter ion. Presented at 22nd Int. Symp. on Chromatography, Rome, Italy, September 13-18, 1998. 

Detailed procedures for the synthesis ofa,o>-organofunctionally terminated siloxane oligomers with well defined structures have been given 50,66-67). Tables 6 and 7 provide the data on the synthesis and characteristics of aminopropyl and hydroxybutyl terminated polydimethylsiloxane oligomers prepared via anionic and cationic ringopening polymerization of octamethylcyclotetrasiloxane (D in the presence of appropriate disiloxanes, respectively. 

Table 10. Characteristics of aminopropyl-terminated poly(dimethyl-diphenyl)siloxane oligomers 66 171)...

The first example of siloxane-urea segmented copolymers were prepared by the direct reaction of aminopropyl-terminated polydimethyl siloxane oligomers and MDI (4,4 -diphenylmethane diisocyanate), in solution at room temperature as shown in the Reaction Scheme XI. 

The effect of structural variations in siloxane oligomers in the synthesis and properties of the resulting siloxane-urea copolymers have also been investigated 161). In these studies aminopropyl-terminated poly(dimethyl-diphenyl)siloxane and poly-... 

Table 14. Synthesis and characteristics of siloxane-urea segmented copolymers based on MDI and aminopropyl terminated PDMS oligomers 1571...

Poly(arylester)-polysiloxane multiblock copolymers have also been synthesized by the interfacial polymerization of aminopropyl terminated polysiloxane oligomers with bisphenol-A and a mixture of isophthaloyl and terephthaloyl chlorides117, 193-1951 as illustrated in Reaction Scheme XV. In these reactions the poly(arylester) blocks are formed in situ during the copolymerization, so the control of their block sizes is not very precise. It is also important to note that since aminopropyl terminated siloxane oligomers are employed, the linkages which connect the arylester and siloxane blocks are amide linkages. 

Siloxane-urea copolymers were synthesized by the reaction of the aminopropyl terminated PDMS oligomers with MDI or HMDI with no chain extenders (Reaction Scheme XI and Tables 14 and 15). Therefore, in these copolymers the hard segments consist of the aminopropyl end groups on the siloxane oligomers and MDI or HMDI backbones as shown below. The soft segment is pure polydimethylsiloxane. 

American scientists prepared the organo-silica sol-gel membranes60 and demonstrated in a single layer format for pH measurement and multiple-layer format for both C02 and NH3. The sensors used a hydroxypyrenetrisulfonic acid (HPTS) as the indicator immobilizes in a base-catalyzed sol-gel containing poly(dimethyl)siloxane, aminopropyl-triethoxysilane (APTES) and tetraethylorthosilicate (TEOS). This indicator gel was over coated with a hydrophobic sol-gel to reduce cross reactivity to pH when either carbon dioxide or ammonia were examined. 

In this paper we will discuss the synthesis of a, urhydroxybutyl terminated polydimethylsiloxane oligomers by cationic routes and a,u-aminopropyl terminated poly(dimethy1-diphenyl)siloxane oligomers by anionic methods respectively. Detailed procedures for the synthesis of aminopropyl, carhoxypropyl and glycidoxypropyl terminated polydimethylsiloxane oligomers have already been described elsewhere(1 1). ... 

Table II provides a summary of the results on the characteristics of aminopropyl terminated poly(dimethyl-diphenyl)-siloxane oligomers synthesized. These reactions were conducted in bulk at 160°C with K0H as the initiator. As can be seen from Table II the stoichiometric number average molecular weights sought and obtained are in very good agreement. The level of diphenylsiloxane incorporation was determined by UV spectroscopy. There is no absorption of dimethylsiloxane backbone in the spectral range of 240 to 280 nm. On the other hand, phenyl groups absorb very strongly over these wavelengths (Figure 3). For quantitative analysis we have used the absorption peak at 270 nm as the reference.

Characteristics of Aminopropyl Terminated Poly(Dimethyldiphenyl)siloxane Oligomers... 

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