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1

Modification of poly(vinyl chloride) by aromatic amines: application to the extraction of some metal cation

Mabrouki Adnen, Ammari Fayçel

Polimery

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2021

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T. 66, nr 7-8

389--398

EN

The reaction of poly(vinyl chloride) (PVC) with various aliphatic amines in 1,4-dioxane has been studied. These reactions led to the formation of new polymers (PVC-L), which were characterized by different spectroscopic methods: differential thermal analysis (DTA) and infrared. The extraction percentages were determined by comparing the initial conductivity of the aqueous solution containing the studied metal with the final conductivity of the aqueous solution at extraction equilibrium. One of the obtained polymers gave an extraction rate of 82.05% for Li +, which underlines the importance of the substitution of chlorine atoms by diethylenetriamine groups. A kinetic study of the extraction shows that the optimal duration of extraction was obtained with the polymer most substituted by diethylenetriamine groups.

PL

Badano reakcję poli(chlorku winylu) (PVC) z różnymi aminami alifatycznymi w 1,4-dioksanie. Reakcje te doprowadziły do powstania nowych polimerów (PVC-L), które charakteryzowano metodami różnicowej analizy termicznej (DTA) i podczerwieni. Procent ekstrakcji określano przez porównanie początkowej przewodności roztworu wodnego zawierającego badany metal z końcową przewodnością roztworu wodnego w stanie równowagi ekstrakcji. Dla jednego z otrzymanych polimerów uzyskano stopień ekstrakcji 82, 05% dla Li +, co podkreśla znaczenie podstawienia atomów chloru przez grupy dietylenotriaminowe. Badania kinetyczne wykazały, że optymalny czas ekstrakcji uzyskano dla polimeru z najbardziej podstawionym grupami dietylenotriaminowymi.

2

Functional groups grafted on poly(vinyl chloride) – evaluation of new modified polymers in metal ions adsorption

Mbarki F., Ammari F., Amor A. B. H., Meganem F.

Polimery

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2017

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T. 62, nr 2

109--117

EN

Poly(vinyl chloride) (PVC) has been subjected to numerous chemical modifications which were undertaken in order to improve its properties, the use of PVC in new applications and understanding of PVC-related phenomena. This work describes the chemical modification of PVC by amino groups (benzylamine and diethylenetriamine) through nucleophilic substitution reactions of its chlorine atoms to obtain P1 polymer. The modified polymer was subsequently reticulated with dichlorodiethyl ether to obtain P2 polymer. The obtained polymers were characterized using infrared spectroscopy (FT-IR), elemental analysis (CHN), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), differential thermal analysis (DTA), and X-ray diffraction (XRD). The modified polymers (P1 and P2) were tested for metal ion extraction (cadmium, cobalt, lead, or chromium) using the solid-phase extraction (SPE) method and the inductively coupled plasma atomic emission spectrometry (ICP-AES) technique. Quantitative adsorption measurements were performed using solutions containing 2 • 10-4M of heavy metal ions with pH = 3.5–4.5 at a flow rate of 0.6 dm3/min. The new extractants based on modified PVC (P1 and P2) were able to remove the negative effects of heavy metals contained in aqueous solutions. For Pb2+, the extraction percentage was 98 % using P1 and 90.3 % using P2.

PL

Przeprowadzono chemiczną modyfikację poli(chlorku winylu) (PVC) w reakcji nukleofilowego podstawienia atomów chloru grupami aminowymi (benzyloamina i dietylenotriamina). Otrzymany polimer P1 szczepiono następnie eterem dichlorodietylowym – uzyskano polimer P2. Wytworzone polimery scharakteryzowano za pomocą spektroskopii w podczerwieni (FT-IR), analizy elementarnej (CHN), różnicowej kalorymetrii skaningowej (DSC), analizy termograwimetrycznej (TGA), różnicowej analizy termicznej (DTA) i dyfrakcji rentgenowskiej (XRD). Polimery P1 i P2 testowano w procesie ekstrakcji jonów metali (kadmu, kobaltu, ołowiu lub chromu), stosując ekstrakcję w fazie stałej (SPE) imetodę atomowej spektrometrii emisyjnej z plazmą wzbudzaną indukcyjnie (ICP-AES). Pomiary ilościowe adsorpcji prowadzono w roztworach wodnych zawierających 2 • 10-4M jonów metali ciężkich, opH=3,5–4,5 i przy szybkości przepływu 0,6 dm3/min. Nowe ekstrahenty na bazie zmodyfikowanego PVC (P1, P2) adsorbowały metale ciężkie zawarte w roztworach wodnych – w wypadku jonów Pb2+ ekstrakcja za pomocą P1 wyniosła 98 %, a za pomocą P2 – 90,3 %.

3

Zastosowanie trietyloaminy w syntezie organicznej

Kowalski P., Sikorska-Jarosz J.

Wiadomości Chemiczne

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2003

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[Z] 57, 11-12

1133--1162

EN

This review shows examples of application of Et3N in oxidations, eliminations, substitutions, and addition reactions. Triethylamine (Et3N) appears to be most popular organic amine base in organic synthetic chemistry. The popularity comes from its low price along with easiness of removal by distillation. However, Et3N is a very dangerous fire hazard when exposed to the heat, flame, or oxidizers. Their salts with inorganic acids are somewhat insoluble in most organic solvents of low polarity and for that reason may by removed from the reaction media by simple filtration. Examples of application of Et3N in oxidation reactions are shown in ozonolysis of cycloalkene 1-8 [3-5] (figs 1-4-5), and figs 1-6-8 show oxidation of 1-14, 1-16, and 1-18 alcohols, employing activated DMSO [6-12]. Various oxidation processes of hydrazones with iodide in the presence of Et3N are presented in fig. 1-9 [13]. Elimination reactions, concerned mainly with dehydrohalogenations, are described in examples of halogen derivatives of lactone 2-1 [17], ketone 2-3 [18,19], sulfone 2-6 [20], and acids 2-9 and 2-11 [21,22] (figs 2-1-5). Dehalogenation of 2-13 [23], 2-17 [26-28], and 2-22 [31-37] acid chlorides are presented in figs 2-6-8, while formation of nitrile oxides in figs 2-11-13 [38-42]. Competitive dehydrobromination and dehydrochlorination reaction occurs in the presence of Et3N in 1,1,1-trichloro-3-bromo-3-fenylopropane (2-35) is described in fig. 2-15 [44]. Mechanizm and examples of transformation of chlorosulfonyl chlorides are presented in figs 2-17-20 [47-51], and dimerization of aldiminium salts [63] in fig. 2-25 as well. Applications of Et3N in carbon-carbon bond formation in an intramolecular Heck reaction are shown in fig. 3-1 [70-74]. Example of use of Et3N in enolboronation of carbonyl compounds is described in fig. 3-2 [75-78], and additionally, in synthesis of silyl enol ethers can be found in figs 3-3-6 [89-104]. Application of Et3N as the base in neutralizing the acids liberated in preparing diazo ketones and mixed anhydrides are indicated in fig. 3-7 [105-107] and fig. 3-8 [108-117] respectively, while in protecting of hydroxy group in figs 3-9-11 [118-126]. Use of Et3N as the effective catalyst in cyjanoethylation reaction of active methyl group in acetylacetone (4-2) [130] and alkylpyridine methiodides 4-4-5, 4-8-9 [131] are shown in figs 4-1-3, and in isomerization reaction of pyrazolines 4-14 [133] and cycloaddition of indane-1,3-dione (4-16) [134] in figs.4-5?6.