ABSTRACT: In this research two kinds of pure polytetrafluoroethylene (PTFE) (C 2 F 4 ). China_UAE source prepared from solution cast as film and strip have been studied by mechanical properties (Tensile testing instrument) subjected to different temperature heating cycle. Both modifications show variation inelongation at yield, stress at yield, elongation at break, stress at break, and young modulus) when temperature is changed. It seems that the product company of China is better than the product company of UAE in mechanical properties of this polymer

Dr May A S Mohammed

Rand B Lutfi

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ISSN: 2350-0328 
International Journal of Advanced Research in Science, 
Engineering and Technology 
Vol. 3, Issue 3 , March 2016 
 
Copyright to IJARSET                                                           www.ijarset.com                                                                        1581 
 
 
Different Mechanical Properties between Two 
Types of PTFE Subjected to Heat Treatment 
 
Dr.May A.S Mohammed , Rand B. Lutfi 
Physical Department, College of Education For Pure Science/ Ibn Al-haytham, Baghdad University, Adamiyia, 
Baghdad-Iraq. 
 
ABSTRACT: In this research two kinds of pure polytetrafluoroethylene (PTFE) (C2F4). China_UAE source prepared 
from solution cast as film and strip have been studied by mechanical properties (Tensile testing instrument) subjected 
to different temperature heating cycle. Both modifications show variation inelongation at yield, stress at yield, 
elongation at break, stress at break, and young modulus) when temperature is changed. It seems that the product 
company of China is better than the product company of UAE in mechanical properties of this polymer. 
 
KEYWORDS: PTFE, Mechanical properties. 
 
I. INTRODUCTION 
In this study, one of thermoplastic polymers was used; it is Polytetrafluoroethylene - (PTFE) (C2F4) n. 
Polytetrafluoroethylene is a linear branchless extremely crystalline polymer with a melting point of (327 °C) and 
related to the family of fluoro plastics. 
We have decided to restudy PTEF due to the lack of its mechanical data and its structural complexity. It is an 
exceptional material in many ways; it offers some beneficial properties over the widest temperature range in a better 
way than does any other polymer. It is resistant to almost all caustic and acidic materials and it is insoluble in all 
common solvents. PTFE has the highest resistivity of any material, low dielectric loss and a very high dielectric 
strength. Its availability from many manufacturers and its use as a common engineering material for small high 
performance parts. The sliding friction coefficient between PTFE and many of engineering materials is very low and 
when sintered with wear reducing compounds, an industrially remarkble class of bearing materials is produced [1,2]. 
The mechanical properties of polymer the characteristics exhibited by the material when subjected to externally 
applied mechanical force. In other term, mechanical properties speak about the reaction of a material to applied forces. 
the most natural test of a material’s mechanical properties is tensile test, in which a strip or cylinder of the material, 
having length L and cross-sectional area A, is anchored at one end and subjected to an axial load P – a load acting 
along the specimen’s long axis – at the other. 
The tensile test is popular since the properties obtained can be applied to design different components. The tensile test 
measures the resistance of a material to a static or slowly applied force. The strain rates in a tensile test are typically 
small [3,4]. 
In general, the stress as the force acting per unit area over which the force is applied. Strain is defined as the 
change in dimension per unit length. Stress is typically expressed in Pa (Pascals). Strain has no dimensions [5]. 
The stress over the circular cross section that is perpendicular to the axial load will be: 𝐬= 
𝐅
𝐀
…… (1) 
Where F is the force applied and A is cross-sectional area  
Strain = 
∆𝑳
𝑳
…… (2) 
Where L is the original length and∆L is the change in length [6]. 
        Stress acquired at the highest applied force is called Tensile strength which is the maximum stress on the 
engineering stress strain curve. This amount is usually known as the ultimate tensile strength. At some point, one 
region is deformed more than others and a large, local decrease in the cross sectional area occurs. This locally deformed 
region is called the neck and this state is called necking. At this point a lower force is desired to continue its 
 
 
      
         
        
ISSN: 2350-0328 
International Journal of Advanced Research in Science, 
Engineering and Technology 
Vol. 3, Issue 3 , March 2016 
 
Copyright to IJARSET                                                           www.ijarset.com                                                                        1582 
 
 
 
 
deformation due to smaller cross-sectional area, the engineering stress, determined from the original area A, decreases 
[7]. 
 
      Young’s modulus (E) or the modulus of elasticity is the slope of the stress strain curve in the elastic region. 
Hooke’s Law is the relationship between stress and strain in the elastic region is known [8,9]. 
E = 
𝒔𝒕𝒓𝒆𝒔𝒔
𝒔𝒕𝒓𝒂𝒊𝒏
…. (3) 
II. EXPERIMENTAL 
 
 We used two sets samples of PTFE ribbon with different origins, the first set is a ribbon of polymer (PTFE) China 
origin and the second set is also a ribbon of (PTFE) but Emirates origin. By taking the bar is made of this article 
polymeric that prepared from solution cast as film and strip it has been preparing the two sets of samples in the form of 
a rectangular shape dimensions (14×1.9) cm. 
The behavior of tensile samples was marked at room temperature by utilizing tensile testing instrument model (H50KT) 
produced by (Tinius 
Olsen / UK). Samples were prepared as figure (1) 
 
 
 
 
 
Figure (1)Planner for the dimensions of sample examination 
 
 
         The specimen was loaded at speed 5 mm/min between two grips adjusted by hand for (2000 N) computerized 
tensile test instrument, with an electronic expansion. Load-Elongation curves were recorded and yield stress and strain 
were calculated at the corresponding points to the Load-Elongation curve, we also calculate the amount of strain by 
identifying the difference between primary and final lengths occurring in process of drag when cutting the sampleand 
determine the Young modulus depending on the linear part of the stress-strain curve. 
In this study, four samples of poly (tetrafluoroethylene) (PTFE) were tested at (RT, 100,200,250)
 °
Cto calculate the 
tensile properties of the samples. 
 
 
 
 
 
      
         
        
ISSN: 2350-0328 
International Journal of Advanced Research in Science, 
Engineering and Technology 
Vol. 3, Issue 3 , March 2016 
 
Copyright to IJARSET                                                           www.ijarset.com                                                                        1583 
 
 
 
 
 
III. RESULTS 
 
Load-Elongation curves for two types of PTFE samples are shown in figures (2a) and (2b) respectively. 
From these tensile curves for PTFE, we can get young's modulus, stress at break, stress at yield, elongation at yield. 
 
 
 
And elongation at break, which displayed in tables (1). 
 
Fig. (2a) Load-Elongation curve for PTFE (type 1) with different temperature for polymer poly 
(tetrafluoroethylene) PTFE 
 
Fig. (2b) Load-Elongation curve for PTFE (type 2) with different temperature for polymer poly 
(tetrafluoroethylene) PTFE. 
 
 
      
         
        
ISSN: 2350-0328 
International Journal of Advanced Research in Science, 
Engineering and Technology 
Vol. 3, Issue 3 , March 2016 
 
Copyright to IJARSET                                                           www.ijarset.com                                                                        1584 
 
 
 
By using equation (1) (2) and (3) we calculated stress, strain and Young modulus for PTFE samples for all temperature. 
Table: (1) tensile properties of PTFE for two types 
Type T 
(
°
C) 
Y 
(Mpa) 
σB  
(pa) 
σy  
(pa) 
εB 
(%) 
εy  
(%) 
(1) RT 1.409 18190 16447 0.356 0.118 
100 1.142 22461 24896 0.421 0.21 
200 0.81 46735 29886 1.645 0.419 
250 1.094 47747 37837 2.056 0.5 
(2) RT 2.850 16447 13157 0.237 0.05 
100 2.203 20032 16025 0.515 0.203 
200 0.585 27159 22406 1.013 0.342 
250 0.827 41359 35566 1.209 0.5 
 
  
 From table (1) we can show the decrease in Young modulus with the increase of temperature because of the increase in 
stress with the increase in strain in type (1) slightly higher than type (2) because the strain in type (2) is less than type 
(1) this feature is applied for all semi-crystalline polymers.as in figure (3) below. 
 
Figure (3) shows Young modulus as a function for heat treatment in different temperatures for two types of 
PTFE. 
 
 
In another side the stress at break and stress at yield are increased with the increase of temperature and in type (1) 
which is higher than type (2) that is due to the increase of orientation of the molecular chains for polymer as in figure 
(4) and (5). 
 
 
 
 
 
 
      
         
        
ISSN: 2350-0328 
International Journal of Advanced Research in Science, 
Engineering and Technology 
Vol. 3, Issue 3 , March 2016 
 
Copyright to IJARSET                                                           www.ijarset.com                                                                        1585 
 
 
 
 
Figure (4) shows stress at break as a function             Figure (5) shows stress at yield point as a function for heat  
for heat treatment in different temperatures                                     heat treatment in different temperatures for two types of 
PTFE.       for two types of PTFE. 
 
  
 Figure (6) shows strain at breakdown as a function            Figure (7) shows strain at yield point as a function for heat  
for heat treatment in different temperatures                          heat treatment in different for two types of PTFE. es 
for two types of PTFE. 
 
Figure (6) and (7) show the behavior of strain at break and at yield for two types increase with the increase of 
temperature and in type (1) which is higher than type (2) this is due to making the samples free to shrinkage during heat 
treatment. The increase in the strain attributed to the flexible behavior of the polymer, which explains the carried strain 
of hanging on both crystalline and random areaswith each other. 
 
 
 
 
      
         
        
ISSN: 2350-0328 
International Journal of Advanced Research in Science, 
Engineering and Technology 
Vol. 3, Issue 3 , March 2016 
 
Copyright to IJARSET                                                           www.ijarset.com                                                                        1586 
 
 
IV . CONCLUSIONS 
The heat treatment of polymer to different temperatures in order to know its properties and resistance to 
environmental conditions results showed that the mechanical properties increase linearly with the increase of 
temperature. The heat treatment led to improving the mechanical properties. Heating to (250
°
C) has led to the breaking 
of the bonds and formation of entanglement case which makes it the best and thus improving its properties for the 
appropriate environmental conditions. 
 
 
REFERENCES 
 
1. P.J. Raea and D.M. Dattelbaum, "The properties of poly (tetrafluoroethylene) (PTFE) in compression", Science direct, 45, USA, Vol.45, 
No.22, PP.7615-7625, 2004. 
2. M. Dumitraş "DTA and DSC study on the effect of mechanicalDispersion on poly (tetrafluorethylene) properties", Acta chemical lasi, 
vol.22_No.2, PP.63-74, 2014. 
3. D. Roylance" Introduction to elasticity" Massachusetts Institute of Technology, Cambridge, MA 02139, 2000. 
4. M. Abd al-sattar and N. N. ramo" structural and mechanical different between met and UV stabilize poly amide 6, 6 subjected to heat 
treatment", college of science of al-mustansiriya, Vol.24, N.1, P.127-134, 2013. 
5. E. J. Hearn, "Mechanics of Materials I", Third Edition, Butterworth-Heinemann, UK, 1997. 
6. A. F. Liu "Mechanics and Mechanisms of Fracture: An Introduction", 1st Edition, Materials Park, USA, PP.1-443 2005. 
7. D. R. Askeland, "The Science and Engineering of Materials" sixth edition, Cengage Learning, USA, 2011. 
8. B. S. Mitchell, "An Introduction to Materials Engineering and Science", John Wiley & Sons, Inc. and Hoboken, New Jersey, Canada, 
2004. 
9. M. A. Meyers and K. K. Chawla, "Mechanical Behavior of Materials", Cambridge University Press, UK, Vol.2, PP.420-425, 2009. 
 
 
 
 
 
 
 
 
 
 
 


Different Mechanical Properties between Two Types of PTFE Subjected to Heat Treatment

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Different Mechanical Properties between Two Types of PTFE Subjected to Heat Treatment

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