高分子怎么形成：These long molecules are composed of structural entities called mer units which are successively repeated along the chain.
Fabrication and processing of glasses(玻璃): Glass properties（特性）：
Specific volume（比容）–是指单位质量流体所占的体积，即密度的倒数
Viscosity（粘度）–液体在外力作用下流动时，分子间的内聚力阻碍分子间的相对运动而产生一种内摩擦力，液体的这种性质叫做液体的粘性。其特点是：只有在流动时液体才表现出粘性，静止液体(液体质点间没有相对运动的液体)是不呈现粘性的。
(1) Specific volume： Upon cooling，a glass becomes more and more viscous in a continuous manner with decreasing temperature； There is no definite temperature at which the liquid transforms to a solid as with crystalline materials.
Tm（熔点） For crystalline materials，there is a discontinuous decrease in volume at the melting temperature Tm. However, for glassy materials, volume decreases continuously with temperature reduction；
Tg （玻璃化转变温度） A slight decrease in slope of the curve occurs at what is called the glass transition temperature, or fictive temperature，Tg . Below this temperature, the material is considered to be a glass; above, it is first a supercooled liquid（过冷液体）and finally a liquid.
(2) Viscosity：Logarithm(对数) of viscosity versus temperature for several silica glasses: fused silica，high silica，borosilicate（硼硅酸玻璃），and soda–lime glasses（钠钙玻璃）
Melting point(熔化温度) The melting point corresponds to the temperature at which the viscosity is 10 Pa.s (100 P泊)；the glass is fluid enough to be considered a liquid.
Working point (工作点，加工点) The working point represents the temperature at which the viscosity is 103 Pa.s (104 P)；the glass is easily deformed at this viscosity
Softening point(软化点) The softening point，the temperature at which the viscosity is 4×106Pa.s (4 ×107 P), is the maximum temperature at which a glass piece may be handled without causing significant dimensional alterations.
Annealing point(退火点) The annealing point is the temperature at which the viscosity is 1012 Pa﹒s(1013 P); at this temperature, atomic diffusion is sufficiently rapid that any residual(残余) stresses may be removed within about 15 min.玻璃加工工艺
Strain point(应变点) The strain point corresponds to the temperature at which the viscosity becomes 3 × 1013 Pa﹒s (3×1014 P)； for temperatures below the strain point， fracture will occur before the onset of plastic deformation. The glass transition temperature will be above the strain point.
working range Most glass-forming operations are carried out within the working range—between the working and softening temperatu
res.
GLASS FORMING（玻璃成形过程）：
Four different forming methods are used to fabricate glass products:
pressing，blowing（吹）， drawing，and fiber forming
（1）Pressing：
Pressing is used in the fabrication of relatively thick-walled pieces such as plates（板材） and dishes（盘子）. The glass piece is formed by pressure application in a graphite-coated cast iron mold having the desired shape；the mold is ordinarily heated to ensure an even surface
（2）Blowing
Although some glass blowing is done by hand，especially for art objects， the process has been completely automated for the production of glass jars，bottles，and light bulbs.
From a raw gob（块）of glass， a parison（型坯）， or temporary shape，is formed by mechanical pressing in a mold. This piece is inserted into a finishing or blow mold and forced to conform to the mold contours（轮廓） by the pressure created from a blast of air
（3）Drawing
Drawing is used to form long glass pieces such as sheet，rod， tubing， and fibers， which have a constant cross section.
（4）Fiber forming
Continuous glass fibers are formed in a rather sophisticated drawing operation. The molten glass is contained in a platinum （铂）heating chamber. Fibers are formed by drawing the molten glass through many small orifices （针孔、管孔）at the chamber base. The glass viscosity，which is critical，is controlled by chamber and orifice temperatures.
HEAT TREATING GLASSES：
Annealing（退火）运用适当的温度制度连续不断的把成型的玻璃降至室温，使成型玻璃板中的内应力(残存应力)降至允许范围之内的过程 。When a ceramic material is cooled from an elevated temperature，internal stresses，called thermal stresses，may be introduced as a result of the difference in cooling rate and thermal contraction between the surface and interior regions.
Glass Tempering（回火）
将玻璃加热到某一温度，充分保温后，按一定速度进行冷却的热处理工艺。目的是消除内应力，稳定组织，降低硬度，从而改善玻璃综合性能 With this technique， the glassware is heated to a temperature above the glass transition region yet below the softening point. It is then cooled to room temperature in a jet of air， or in some cases， an oil bath. The residual stresses arise from differences in cooling rates for surface and interior regions.
processing and fabrication methods of polymer:processing methods 加工方法：1、热塑性材料：blend（共混）coextrusion（共挤出）2、rubber 橡胶：plastication（塑炼）milling，mixing（混炼）
fabrication methods 成型方法：1、molding（模塑）2、compression and transfer molding3、injection（注射）molding4、extrusion molding（挤出成型）5、blow molding
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