Melting Temperatures of Polymers - METTLER … · Application Notes Excellence Melting Point...
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Transcript of Melting Temperatures of Polymers - METTLER … · Application Notes Excellence Melting Point...
Applic
atio
n N
ote
s
Excellence Melting Point Systems by METTLER TOLEDO measure the melting point or melt-
ing range of polymers very accurately. They are best suited to determine the correct melt-
ing temperature for molding machines.
Why melting temperature of polymers is important
Often the quality of raw polymers has to be tested before they are used for injection molding. Among other tests
the melting range is determined in order to set the recommended melting temperature. The melting temperature
is the temperature the material should be as it leaves the molding machine and enters the mold. This tempera-
ture is different for every material made, and should be held as close as possible by the molder to attain parts
with expected physical, mechanical and thermal properties. That is why the melting temperature setting of the
molding machine is so important.
Suitable standard
In order to achieve comparable results the determination should follow a certain standard which determines
sample preparation, method parameters and how to report. Such a standard is EN ISO 3146.
Excellence Melting Point Systems
Melting Temperatures of Polymers
elting Point Systems by METTLER TOLEDO measure the melting
polymers very accurately. They are best suited to determine t
ure for molding machines.
mperature of polymers is important
www.mt.com/one-click-meltingFor more information
Mel
ting o
f Poly
mer
s
Mettler-Toledo AG, Analytical
CH-8603 Schwerzenbach, Schweiz
Telefon +41-44-806 77 11
Fax +41-44-806 72 60
Internet www.mt.com
Subject to technical changes
©08/2011 Mettler-Toledo AG
(electronic publication only)
Especially the contained capillary method provides an
easy and fast method for this quality control task
which even can be automized.
Simple and efficient
Best suited for carrying out such analyses are the Ex-
cellence Melting Point Systems. They offer accurate
determinations thanks to the measurement principle
and video camera recording, efficient workflows due to
One Click™ melting points and automatic detection
and are really easy to operate which means close to
no training required before you start to productively
work with the systems.
Accurate results
The instrument records a transmission light and a re-
flected light video. The images of the transmission light
video are evaluated by digital image analysis. This
delivers an intensity curve which is shown in figure 1.
The measurement can be visually reviewed by replay-
ing the video on the instrument or offline on a com-
puter by playing the AVI-video. Two images extracted
from the reflective light video which correspond to the
start and the end of melting of the material shown in
figure 1 are displayed in figure 2. The material mea-
sured is a polyethylene homopolymer powder. On the
intensity curve characteristic temperatures such as
start of melting and end of melting can be evaluated.
Customers use MP systems for polymer quality
control
A worldwide present supplier of sports equipment de-
cided to rely on METTLER TOLEDOs MP90 Melting
Point Systems for the quality control of polyurethane.
Beyond other application areas the material is part of
the soles of different types of sport shoes.
After thorough testing and application development
several instrument were purchased and fulfill their
tasks in various factories around the world now.
Figure 1: Typical intensity curve resulting from a determination of a
polyethylene homopolymer powder. It shows the light transmission
intensity versus temperature. The start of melting is evaluated at
around 5% transmittance. The end of melting is evaluated at the
dramatic slope change around 98.5 °C towards the end of mea-
surement.
Figure 2: Images taken at the characteristic melting events. Top:
Start of melting at 89.3 °C, Bottom: End of melting at 98.5 °C. The
temperature is displayed in each video.