Synthesis , Characterization and Biological Activities of new Nano Schiff bases Composites

New nano composites containing Schiff bases have been synthesized and presented in this paper. All compounds have been categorized through FT-IR and some of them by H-NMR spectroscopy. The antibacterial performance of the prepared compounds has been investigated according to the agar diffusion method. The compounds (P1, P2, C1, and C2) have shown, in general, significant inhibition against bacterial.

Interface area between fillers and matrix [6]. Many of the inorganic minerals have hydrophilic surfaces and are not favorable with most hydrophobic polymer matrices. The purpose of fillers surface modification is to confirm their hydrophobization with the polymer in order to make intercalation or exfoliation [7]. Chemical grafting of polymers onto inorganic particles can be gotten via covalent bonding with the hydroxyl groups on the unmodified particle surface [8,9]. For more than hundred and fifty years, schiff bases (SBs) have still been Avery essential kind of organic compounds in chemical, medical, biochemical, and pharmaceutical areas. SBs have been given a huge range of organic activities like antimalarial, antipyretic, and antibacterial activities [10].
A solution of (0.01 mol), 1.34gm, of (Tere Phthaldehyde) in (20) ml of absolute ethanol, (0.02 mol),2.18 gm of (4-aminophenol) was added. Then, number of drop glacial acetic acid was added as a catalyst. The reaction mixture was heated under reflux for 4 hours. Then, this reaction mixture was cooled and the product was stirred. Lastly, it was filtered and purified by recrystallization based on hot water with m.p (264-266) °C and yield 79.5% [12].

Preparation of 4-((4-bromobenzylidene) amino) pheny methacrylate (4):
Compound 4 was prepared by the same preparation procedure of compound 3 but using 0.01mol, 2.76 of compound 2 with 0.01mol, .045 gm of methacryloyl chloride.m.p (99-101),yield 80%. (5): [14]. About 1.0 g of nano alumina in flask with 20 ml toluene was stirred. At that time, 3.0 g of acrylic acid monomer was added drop wise. The reacted mixture was left for stirring process for (8) hour. Subsequently, the product was filtered and washed initially with 15 ml distilled water and secondly with 15 ml acetone, and dried then under room temperature. [15].

2.8.1Preparation of P1
In a two-neck round-bottom flask, (25) ml of toluene as a solvent was positioned under nitrogen atmosphere in controlled water bath at (80 º C). After 3 minutes, 0.15 g of benzoyl peroxide was inserted. Then, 3 g of compound 3 was added, and left for stirring process for 5 hours. The product was filtered and washed primarily with 10 ml toluene and then with 10 ml acetone, dried under room temperature.

2.8.2Preparation of P2
Polymer P2 was prepared based on the same method of polymer P1, using compound 4.

Preparation of Nanocomposites (C1, C2): [15]
2.9.1 Preparation of C1 Nanocomposite C1 was prepared by the same process of P1 but after inserting benzoyl peroxide. About 2.5 g nano alumina grafted acrylic acid and then 2.5 g of compound 3 were sequentially added.

preparation of C2
This Nanocomposite was prepared by the same sort of C1 but with compound 4.

Biological Activity
The antibacterial-activity of the prepared compounds (P1, P2, C1, and C2) was performed in relation to the agar diffusion method. The prepared compounds were tested against bacillus ceru, bacillus sabtillus, staph. Each compound was dissolved in 2ml DMSO in concentration (0.024 M). The plates were then incubated at 37ºC and examined after 24 hrs.

Results and Discussion
The structures of all synthesized compounds were confirmed by using FT-IR spectral. It was a good evidence corresponding to the structure of suggested compounds and some of the compounds by H-NMR.

Characterization of Schiff-baes Compounds (1, 2).
The compound (1) was prepared by reacting Tere Phthaldehyde with 4-amino phenol in absolute ethanol. Figure 1. Depicts browed peak at (3417) cm-1 that is related to the (O-H), stretching. An observed band at 1620 cm -1 is assigned to C=N isomethane, and showed disappeared band of primary (NH2) and carbonyl of aldehyde. The compound (2) has equipped by reacting 4-bromobenzaldehyde with 4-amino phenol in absolute ethanol. Figure  2. Depicts the following absorption bands: O-H stretching is at (3105) cm -1 . It as well shows a peak at (1621) cm -1 due to the C=N and also disappeared band of primary (NH2) and carbonyl of aldehyde.

3.2Characterazation of Esters Compounds (3, 4).
Compounds (3,4) were categorized through FT-IR and H-NMR spectral tools. The compound (3) was prepared by reacting compound (1) with methacryloyl chloride in THF. Based on FT-IR, Figure 3. Illustrates the strong peak at (1743) cm -1 that is related with the C=O stretching. Stretching band of (C=N) showed absorbance at 1618cm -1 with disappeared band of O-H. The H-NMR spectrum for compound 3 showed signals at d = 1.25 ppm for 3 protons of (CH3) groups signals seemed at d =6.82 ppm for two protons of (CH2) groups with multiple signals in the region with d =7.3-8.4 for aromatic protons. The signal at d=9.99 ppm is for one proton of C=N as in Figure 4. The compound 4 xprimed by reacting compound (2) with methacryloyl chloride in THF. Figure 5. X illustrated disappeared band of O-H, band at approximately 1737 cm-1 related with stretching vibration (C=O) of ester. The stretching band of (C=N) showed an absorbance at 1612cm-1. It also showed appearance features bands at (2916-2850) cm-1 of Aliphatic (CH3). The H-NMR spectrum showed signals at d = 1.19 ppm for three protons of (CH3) group, multiple signals in the region of d =6.5-7.5 for aromatic protons. The signal at d=9.49 ppm was for one proton of C=N as explained by Figure 6.

3.3Characterazation of Nanoalumaina-graft Acrylic Acid Monomer.
Nanoalumina-graft acrylic acid monomer was organized by grafted nanoalumina with acrylic acid. The structure of this compound was investigated through FT-IR spectroscopy. By FT-IR, Figure 7. Depicts the following absorption bands C=O stretching at 1751cm-1. Also, it shows the peak at (3487) cm -1 as a result of the O-H.

Charchteraztion of Polymer (P1, P2)
The polymers were prepared by free radical polymerization. Those polymers were considered by FT-IR spectroscopy. The characteristic absorption bands of the polymer (P1) as in Figure 8. Showed strong peaks at (2916-2850) cm-1 of absorption. Alkyl groups (C-H) and the FT-IR spectrum also showed disappearance the peak of (C=C) group which verified the formation of the polymer. Figure 9. For polymer (P2) showed peaks at (2916-2848) cm-1 of absorption Alkyl groups (C-H). FT-IR as wellx depicted disappearance of a peak of (C=C) group.

Charchteraztion of Nanocomposite
The nanocomposite was prepared by polymerization of nanoalumina grafted -acrylic acid once with compound 3 once more with compound 4. By FT-IR spectrum, Figure 10. Of nanocomposite C1 showed the appearance of x stretching bands of alkyl groups (C-H) at (2927-2850). On the other hand, FT-IR disappearance band of (C=C) group. The FT-IR spectrum of nanocomposite C2 in Figure 11. Depicted strong band in region between (2916-2848) due to absorption of alkyl groups (C-H) and also disappearance band of (C=C) group.

Biological activity Results.
The resulting data of biological activity were listed in Table 1. All compounds (P1, P2, C1, and C2) were given inhibition in contradiction of bacteria (b. staph , b.cerus). But with (b. sabtillus), there was no any inhibition.

Conclusions
In this article, new nanocomposites were created, and their biological activities were investigated regarding their structure. The chemical structures of these nanocomposites and their polymers were examined by FT-IR spectroscopy. The results were in agreement with the considered molecular structure.