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Which is stronger: Glue or tape? - Elizabeth Cox
学习统计
CEFR 等级
难度
字幕 (78 片段)
The oldest glue in the world is over 8,000 years old
and comes from a cave near the Dead Sea.
Ancient people used this glue,
made from a mixture of animal bone and plant materials,
to waterproof baskets and construct utensils.
And for thousands of years after,
plants and animals were the glue that held human civilization together.
Today, we have enough types of tape and glue to build and repair almost anything.
But what gives glue and tape their stickiness?
And is one stronger than the other?
Adhesives can be made from synthetic molecules
or natural proteins and carbohydrates
like the vegetable starch dextrin,
the milk protein casein,
and the terpenes in tree resin.
In order to work, glue and tape need both adhesive bonds and cohesive bonds.
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