During this research accomplish some chemical modifications on the Poly for new modified polymers with Kimaaaúah qualities, physical and unexpected new applications that the first of these chemical modifications that was completed is the introduction of a poly styrene butadiene swash and then this group

تم خلال هذا البحث انجاز بعض التحويرات الكيمائية على بولي للحصول على بوليمرات محورة جديدة ذات صفات كيمييائية وفيزيائية ولها تطبيقات جديدة متوقعة ان اول هذه التحويرات الكيمائية التي انجزت هي ادخال مجموعة على البولي ستايرين بيوتادايين ومن ثم اختال هذه المجموعة

modification of polystyrene co butadiene

This study is the second stage of the paper “Studying the Effect of Rubber- Silicone on Physical Properties of Asphalt Cement”. The present study examines the effect of additives on asphalt mixture performance. Asphalt mixture has been designed by Marshall Method for determining the optimum asphalt content and geophysical properties of mix according to ASTM (D-1559). Rubber-silicone at different percentages (1%, 2%, 3% and 5%) was added to asphalt binder. Six specimens of asphalt rubber silicone mixture (ARSM) for each percentage are prepared and evaluated according to Marshall method. Diametric tensile creep test ASTM (D-1075) at 60 Co was used to evaluate permanent deformation and modulus of elasticity for ARSM. The study showed that the Rubber-Silicone has more effects on performance of asphalt mixture by increasing the Marshal stability, air voids, and reducing the flow and bulk density compared with the original mix. It also increases the flexibility properties of the mix and this appears from reducing the permanent deformation at test temperature (60C), the reduction percent is about (30 to 70) %.

هذه الدراسة تمثل الجزء الثاني والمكمل لدراسة تأثير إضافة المطاط السلكوني على الخواص الفيزيائية لمادة الإسفلت الإسمنتي.البحث تناول دراسة تأثير إضافة المطاط السلكوني على أداء الخلطة الإسفلتية. صممت الخلطة الإسفلتية بواسطة طريقة مارشال لتحديد المحتوى الامثل للإسفلت وتحديد الخواص الجيوفيزيائية للخلطة بموجب المواصفة الأمريكية القياسية تحت البند ASTM D-1559 .أضيف المطاط السلكوني الى الإسفلت كنسبة وزنية بنسب مختلفة (1%, 2%, 3%, 5%) وتم إعداد ستة نماذج من الخلطة الإسفلتية المضاف إليها المطاط لكل نسبة وقيمت بموجب طريقة مارشال.كما قيمت التشوهات الدائمية للخلطة عن طريق فحص الكلل للشد القطري بموجب المواصفة القياسية الأمريكية ASTM D-1075 عند درجة حرارة (60) م وتحديد معامل الجساءة لها. أظهرت الدراسة ان لإضافة المطاط السلكوني تأثير كبير على ادا الخلطة الإسفلتية من خلال زيادة قوت الثبات و نسبة الفراغات وتقليل مقدار التشوه والكثافة الكلية بالمقارنة مع الخلطة الأصلية. بالإضافة الى ذلك فقد ازدادت خاصية المرونة للخلطة من خلال تقليل التشوهات الدائمة عند درجة الحرارة (60) م حيث تراوحت نسبة التقليل من (30 الى 70)%.

asphalt mixture --- modification --- additives --- rubber-silicone --- performance

Cadmium (Cd) modified aluminium–silicon cast alloys are well known for their outstanding mechanical properties as they combine excellent strength with good ductility that is due to a modification of brittle Si in the eutectic with traces of Cd (0.2–1.0 wt%). The results showed that the Cd leads to the refinement of eutectic silicon from ~95 to 10µm. The alloys which used in this work were Al-7Si alloy with additions of 0.2, 0.6 and 1 wt% Cd as well as Al-7%Si with out Cd addition. The effect of keeping time also studied and the results indicate that the addition of 1%Cd with keeping time 3min was the best (about 10 µm).

تكون مصبوبات سبائك الألمنيوم-سليكون، المعدلة بنيتها البلورية بإضافة كميات محسوبة من الكادميوم، ذات خواص ميكانيكية عالية. وهذه الخواص ناتجة عن الجمع بين المتانة العالية والمطيلية الجيدة والناتجة عن تعديل البنية البلورية لطور السليكون الايوتكتيكي من شكل رقائق أو صفائح هشة إلى شكل خيطي منتظم وذلك بفعل إضافة الكادميوم لغاية 1% كمعدل للبنية البلورية. تشير نتائج فحص البنية المجهرية لطور السليكون الايوتكتيكي إلى أن المصبوبة المضاف إليها كادميوم بنسبة 1% قد يصل تحول هذا الطور من شكل ابري أو رقائقي ذو طول حوالي 95 مايكرون إلى خيطي بطول حوالي 10 مايكرون . إن السبائك التي تم دراستها في هذا البحث هي ألمنيوم-7%سليكون بإضافة الكادميوم بنسب(0.2، 0.6 و 1.0%) إضافة إلى السبيكة الأصلية بدون إضافات. كذلك تم دراسة تأثير وقت الحفظ عند درجة حراة إضافة الكادميوم وقد أظهرت النتائج إن المصوبة التي أضيف لها الكادميوم بنسبة 1.0% ووقت حفظ 3 دقائق كانت هي الأفضل (طول السليكون الايوتكتيكي الخيطي10 مايكرون).

Casting --- Solidification --- Microstructure --- Al alloys --- Modification

The purpose of this study is to improve the specifications of cut back asphalt (S125) in order to use in the treatment of holes, potholes and cracks of roads. Different methods were carried out to enhance physical and mechanical properties and to get better construction behavior. These treatments are:-First: The vacuum distillation of S125 cut back asphalt was employed to remove oil, vacuum gas oil and vacuum residue as a rapid curing. FTIR spectra of the four fractions of S125 were recorded. It was observed a low penetration and high softening point for the vacuum residue.Second: extraction method using ethanol as a solvent was employed to extract light component that could be in the S125 cut back asphalt. The results indicated that the softening point was highly increased and the penetration as well as ductility was decreased to minimized level.Third: Some Polymers were used as cross linking agent such as melamine and phenol formaldehyde resins. Fourth: The unsaturated monomers were polymerized free radically to increase the solidification of S125. Fifth: The hydrated white cement was used as additive to the S125 cutback asphalt at different ratios to improve the properties. This method was observed as a suitable and economic method, and easy employed compared to others and the best rheological behaviors were given in this method. Also the vacuum distillation method gave high improvements in rheological properties for asphalt residue.

: Liquid asphalt --- Modification --- Cut back S125.

Stone Matrix Asphalt (SMA) is a gap-graded mix that is gaining popularity worldwide. SMA does not application in Iraq; in order for adopt the use of SMA mixtures particularly on high volume roads such as highways and urban intersections in Iraq. So, the new methodology has to be evaluated using Iraq materials and conventional laboratory methods to insure good performance in the Iraq's highway. The purpose of this study is to evaluate the effect of additives type and content on the performance of stone matrix asphalt mixtures. A detailedlaboratory study is carried out by preparing asphalt mixtures specimens using aggregate from Al-Nibaay, (40-50) grade asphalt from dourah refinery and two types of fiber (carbon fiber and polypropylene fiber) with percentages (0.2, 0.3, 0.4, 0.5%) by weight of total mix and two types of polymer (phenol and polyethylene) with percentages (7.5, 10, 12.5, 15%) by weight of total mix were tested in the laboratory. Compacted mixtures were tested to evaluate the effects on SMA bulk specific gravity, maximum specific gravity, void content, MarshallStability, Indirect Tensile Strength (ITS) and permanent deformation. Three different tests temperatures (20, 40,60C°) were employed in the creep test and two temperatures (5, 25 C°) were used in indirect tensile test to investigate the susceptibility of these mixes to change in temperature. The results clearly indicate the importance of using the proper type of stabilizing additive. According to the study results, polymers additives were found to be more effective than fibersadditives. SMA Mix modified with phenol additives can be used in cold and normal temperature area, whereas SMA Mix modified with polyethylene additive can be used in high temperature area.

SMA --- Polymer modification --- Phenol resin --- creep test --- tensile strength