Yeni bir katyonik gemini surfaktant sentezi ve yüzey özellikleri
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Dosyalar
Tarih
2016
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Trakya Üniversitesi Fen Bilimleri Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/restrictedAccess
Özet
Gemini veya dimerik surfaktantlar bir spacer grupla bağlı yüklü veya yüksüz iki amfifilik molekülden ibarettir. Keza ticari (monomerik) surfaktantlar tek kuyruğa bağlı bir polar veya apolar baş gruba sahiptirler. Spacer’in kimyasal yapısı, uzunluğu ve yapısal bükülebilirliği değişebilir. Böylece geniş surfaktant sınıf elde edilir. Gemini surfaktantlar uygun ticari monomerik surfaktantlardan oldukça fazla yüzey aktifliğe, düşük kritik misel konsantrasyonu (KMK) ve çok düşük Krafft noktası değerlerine sahiptirler. Onların süper özelliklerinden dolayı yeni Gemini surfaktant sentezi zordur. Bu çalışmada, hidroksil spacer gruplu yeni bir katyonik gemini surfaktant, N1,N3-diheksadesil-2-hidroksi-N1,N1,N3,N3-tetrametilpropan-1,3-diamonyumbromür (16-3OH-16) sentezlendi, saflaştırıldı ve karakterize edildi. Sentezlenen gemini surfaktantın Krafft noktası, kritik misel konsantrasyonu, iletkenlik, yüzey gerilimi, viskozite, agregasyon sayısı, yoğunluk ve görünür molar hacim gibi fiziksel özellikleri tayin edildi. Konduktometrik, tensiyometrik, viskozimetrik ve spektrofotometrik metotlar kullanılarak sentezlenen gemini surfaktantın KMK değeri yaklaşık 1,8 x 10-4 M olarak bulundu. Ticari surfaktant olan CTAB için de aynı metotlar kullanıldı ve CTAB nin 9.25 x 10-4 M KMK değeri olarak bulundu. Gemini surfaktant ve CTAB’nin Spektrofotometre ile yapılan ölçümler sonrası misel agregasyon sayıları (Nagg) sırasıyla 38 ve 84 olarak bulundu. Ubbelohde viskozimetresi ile viskozite değerleri bulundu. Yüzey gerilimi ölçümlerinden yararlanılarak maksimum yüzey alanı konsantrasyonu (?max) , yüzey basınç KMK. (?KMK) ve adsorpsiyon standart Gibbs enerjisi (???????°)hesaplandı. Saf gemini surfaktant ve CTAB nin belli molar kesirlerinde karışımları hazırlandı ve bu karışımlara saf çözeltilere uygulanan metotlar kullanılarak fizikokimyasal ölçümler alındı. Sentezlenen Gemini surfaktantın, CTAB’nin ve ikili karışımların mikrobiyal ölçümleri TUTAGEM merkezinde yapıldı. Bazı karışımların bazı bakteriyel için anti bakteriyel özellik gösterdiği gözlendi.
abstract
The Gemini or dimeric surfactants are composed of two amphiphilic molecules, charged or uncharged, connected by a spacer group. Likewise, commercial (monomeric) surfactants have a polar or apolar head group attached to a single tail. The chemical structure, length and structural bendability of the spacer can be varied, resulting in a broader surfactant class. Gemini surfactants have considerably higher surfactant, lower critical micelle concentration (CMC) and very low Krafft point values than suitable commercial monomeric surfactants. Due to their superb properties, the nowel Gemini surfactant synthesis is difficult. In this work, the novel cationic Gemini surfactant, N1,N3-dihexadecyl-2- hydroxyl -N1,N1,N3,N3-tetramethylpropane-1,3-diammoniumbromide (16-3OH-16) with a hydroxyl spacer group was synthesized, purified and characterized. Physical properties such as Krafft point, critical micelle concentration, conductivity, surface tension, and viscosity, the number of aggregations, density and visible molar volume of the synthesized Gemini surfactant were determined. The CMC values of the Gemini surfactant synthesized using conductometric, tensiometric, viscosimetric and spectrophotometric methods were found to be about 2 x 10-4 M. The same methods were used for CTAB (the commercial surfactant) and the value of CMC was found to be 9.25 x 10-4 M. The number of mycelial aggregates (Nagg) after measurement with spectrophotometer for Gemini surfactant and CTAB were found to be 38 and 84, respectively. Viscosity values were found with Ubbelohde viscometer. The maximum surface area concentration (?max), surface pressure at CMC(?CMC) and adsorption standard Gibbs energy(???????°) were calculated using the surface tension measurements. Mixtures of pure Gemini surfactant and certain fractions of CTAB were prepared and physico-chemical measurements were taken using these pure solutions. Microbial assays of the synthesized Gemini surfactant, CTAB and binary mixtures were performed at the TUTAGEM center. It has been observed that some blends show antibacterial properties for some bacteria.
abstract
The Gemini or dimeric surfactants are composed of two amphiphilic molecules, charged or uncharged, connected by a spacer group. Likewise, commercial (monomeric) surfactants have a polar or apolar head group attached to a single tail. The chemical structure, length and structural bendability of the spacer can be varied, resulting in a broader surfactant class. Gemini surfactants have considerably higher surfactant, lower critical micelle concentration (CMC) and very low Krafft point values than suitable commercial monomeric surfactants. Due to their superb properties, the nowel Gemini surfactant synthesis is difficult. In this work, the novel cationic Gemini surfactant, N1,N3-dihexadecyl-2- hydroxyl -N1,N1,N3,N3-tetramethylpropane-1,3-diammoniumbromide (16-3OH-16) with a hydroxyl spacer group was synthesized, purified and characterized. Physical properties such as Krafft point, critical micelle concentration, conductivity, surface tension, and viscosity, the number of aggregations, density and visible molar volume of the synthesized Gemini surfactant were determined. The CMC values of the Gemini surfactant synthesized using conductometric, tensiometric, viscosimetric and spectrophotometric methods were found to be about 2 x 10-4 M. The same methods were used for CTAB (the commercial surfactant) and the value of CMC was found to be 9.25 x 10-4 M. The number of mycelial aggregates (Nagg) after measurement with spectrophotometer for Gemini surfactant and CTAB were found to be 38 and 84, respectively. Viscosity values were found with Ubbelohde viscometer. The maximum surface area concentration (?max), surface pressure at CMC(?CMC) and adsorption standard Gibbs energy(???????°) were calculated using the surface tension measurements. Mixtures of pure Gemini surfactant and certain fractions of CTAB were prepared and physico-chemical measurements were taken using these pure solutions. Microbial assays of the synthesized Gemini surfactant, CTAB and binary mixtures were performed at the TUTAGEM center. It has been observed that some blends show antibacterial properties for some bacteria.
Açıklama
Anahtar Kelimeler
Viskozimetrik Yöntem, Antimikrobiyal Çalışmalar, Katyonik Gemini Surfaktant, Konduktometrik Yöntem, Spektrofotometrik Yöntem, Agregasyon Sayısı, Viscosity Method, Antimicrobial Studies, Cationic Gemini Surfactant, Conductometric Method, The spectrophotometric Method, Aggregation Number
