Heat Distortion Temperature (softening temperature) The molecular structure of PVC is made of continuous carbon- carbon single bonds in the main chain. As this main chain is highly flexible, PVC products have the disadvantage of having a low heat distortion temperature (softening temperature) compared with other plastics of the similar molecular structure.
This philosophy greatly impacted the Greek civilization. Athens was the intellectual center of Greece. It was one of the first city-states of its time, and is still world renowned as one of the most famous cities in the world. It was named after Athena, the goddess of wisdom and the city's patron.his philosophy greatly impacted the Greek civilization. Athens was the intellectual center of Greece. It was one of the first city-states of its time, and is still world renowned as one of the most famous cities in the world. It was named after Athena, the goddess of wisdom and the city's patron.
Athens was the largest city in Greece, and controlled a region called Attica. Between the many mountains were fertile valleys, with many farms. Athens became rich because Attica also had valuable sources of silver, lead and marble. Athens also had the biggest navy in Greece. Athens was a beautiful and busy city. People came to the city from all over Greece, and from other countries, to study and to trade. The city's most famous building was the temple called the Parthenon.