الفهرس 
Packaging and Flexible PackagingOnly 14 pages are availabe for public view
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Abstract
Polyurethanes are one of the most important industrial products exhibiting
versatile properties suitable for use in many fields as coatings, adhesives,
sealants, and foams. Considering the continuous depletion of fossil feed
stocks, dramatic fluctuations in the oil price, and environmental issues,
academic and industrial researchers are devoting increasing attention and
efforts to the utilization of renewable resources with comparable properties
as raw materials for the production of polyurethanes. This research is
focused on exploiting vegetable oils in the preparation of biobased polyols
and polyurethanes due to their low toxicity, inherent biodegradability, ready
availability, and relatively low price. Vegetable oil-based polyols are another
promising monomer, which can react with diisocyanates to afford
polyurethane elastomers which have various applications in printing inks and
coatings.
Chapter 1 contains a general introduction about various types of polymeric
packaging sheets and films. Types of printing techniques and inks used based
on their specific functions both the film and the ink.
In chapter 2, Synthesis of polyurethane elastomers prepared via the
prepolymer method was adopted; the PU was characterized for the the
following features:
1. Chemical structre validation for both reactants and products using
Fourier transform infrared (FT-IR) spectroscopy in absence and
resence of chain extenders, diisocyantes and polyols.
2. Molecular weight determination (Mw, Mn, and DP) using Gel
Permeation chromatography (GPC),
3. Flow and fluidity character was achieved through viscosity
measurements.
4. Solid content and solubility in common solvents.5. Printing ink films were designed using these PUEs as a plasticizer
and their optical properties were tested by X-rite, gloss. Other
properties such as mechanical properties as crinkle test, curling
resistance and adhesion strength, and thermal properties as heat and
freeze resistance were examined.
The results proved that the samples of PUEs were hydrophobic and
this nature was increased as the chain extender length was increased,
also all PUEs show low molecular weights and viscosities. Thermal
tests was performed to analyze the thermal behavior of the printing
inks which showed that all the PUEs were stable up to 200 oC and
showed very good freeze stability. All mechanical tests showed very
good results with slightly increase with aromatic isocyanates.
Chapter 3 describes practically the effect of replacing 50% of petroleum
based polyol by castor oil and vegetable oil-based polyols prepared by ringopening of epoxidized vegetable oils (soybean and palm olein) with different
ring openers (Water, Methanol and Ethylene glycol). The properties of the
resulting polyols were investigated. It was characterized for viscosity,
hydroxyl number, acid value, molecular weight, FT-IR, and DSC revealing
all changes with regard to chemical structural features and its prelative
physical properties. Moreover, the properties of final PUs prepared from
castor oil, palm olein polyols and methoxylated soybean oil polyol were
compared with standard PU. The effect of bio-component on the chemical
and thermal stability of resulting PU was again recharacterized for
comparison reasons and efficiency. Printing ink films were designed using
these prepared PUEs as a plasticizer and were tested for optical properties by
X-rite, gloss, mechanical properties as crinkle test, curling resistance and
adhesion strength, and thermal properties as heat and freeze resistance. The
results revealed that the chemical structure of these polyols and their functionality primarily dictate performance properties and their end-use
applications. The results proved also t+hat the samples of biobased PUEs are
found as hydrophobic in nature, in addition, all the PUEs showed low
molecular weights and viscosities. The thermal behavior study of printing
inks indicated that all the PUEs were stable up to 180oC and demonstrate
very good freeze stability except palm olein based polyurethanes (PU PM 50
and PU PW 50). All derived inks from bio-based oils displayed approved
values for the mechanical tests with slightly increase for the samples PU-CO
50 and PU- SB 50.