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玻璃化转变的本质是现代凝聚态物理中最有趣的问题之一. 有理论认为高分子玻璃化转变的本质是: 当主链原子的扩散运动概率 P小于
$ {{\rm{e}}^{ - 2{{\rm{e}}^3}}}$ 时, 必有比例不小于1 + 2e 3/ln P的主链原子扩散运动被冻结. 以该理论的模量温度公式拟合文献的聚苯乙烯模量温度曲线, 得到聚苯乙烯的自由体积膨胀系数值在(0.00045, 0.00052)之间. 以此理论为基础推导得到了玻璃化转变中的比热温度公式: 玻璃化转变中的材料是橡胶和玻璃的混合物, 其中橡胶的比例是自由体积分数的链段中主链原子数次方, 总比热等于两组分各自的比热和比例之积的和. 用聚苯乙烯检验了该比热温度公式, 将计算得到的聚苯乙烯自由体积膨胀系数代入比热温度公式, 不需拟合任何参数公式就能够精准地定量描述聚苯乙烯玻璃化转变中的比热温度关系. 据分析, 聚苯乙烯的玻璃化转变过程是主链原子的扩散运动被激活或者被冻结的过程, 这和非晶合金相关研究结论一致. 以主链原子为摩尔计量单元时, 聚苯乙烯转变中的比热变化为1.61 R( R为气体常数), 这和非晶合金玻璃化转变中比热变化约为1.5 R的规律一致. 这些一致的结论预示非晶合金的玻璃化转变和聚苯乙烯的玻璃化转变具有相同的本质, 以此出发, 提出并证明了非晶合金Pd 40Ni 10Cu 30P 20和聚苯乙烯的比热温度公式是一致的.The nature of glass transition is one of the most interesting problems in modern condensed matter physics. There is a theory that shows that when the particle's diffusion motion probability Pis less than $ {{\rm{e}}^{ - 2{{\rm{e}}^3}}}$ , the proportion of particles whose diffusion motion is frozen is not less than 1 + 2e 3/ln P. Based on the modulus temperature formula of this theory and the experimental modulus-temperature curve of polystyrene in the literature, the free volume expansion coefficient of polystyrene is determined to be in a range of 0.00045－0.00052.In this paper, we first quantitatively study the specific heat temperature relationship in the glass transition of polystyrene. Based on this theory, the specific heat-temperature formula in the glass transition region is derived. The material in the glass transition region is a mixture of rubber and glass, and this two-component (rubber and glass) system’s total specific heat is the product of the specific heat of the rubber and the percentage of rubber in the two-component system plus the product of the specific heat of the glass and the percentage of glass in the two-component system. Let bbe the number of atoms in the main chain of the segment, then the proportion of rubber will be the b-th power of free volume fraction. This specific heat-temperature formula with polystyrene is tested. By substituting the obtained free volume expansion coefficient of the polystyrene into the specific heat-temperature formula, the resulting formula can accurately and quantitatively describe the specific heat-temperature relationship in the glass transition of polystyrene without fitting any parameters. In this paper, we also study the change of motion in the glass transition of polystyrene. According to the analysis, the glass transition process of polystyrene is a process in which the diffusion movement of the main chain atoms is activated or frozen, which is consistent with the conclusions of relevant research on amorphous alloys. When the main chain atom is used as the molar unit of measurement, the specific heat change in the glass transition of polystyrene is 1.61 R( Ris the gas constant), which is consistent with the law, i.e. “the specific heat change in the glass transition of the amorphous alloy is about 1.5 R”. These consistent conclusions predict that the glass transitions of amorphous alloys and glass transitions of polystyrene have the same essence. Based on this idea, the specific heat temperature formulas of the amorphous alloy Pd 40Ni 10Cu 30P 20and polystyrene are verified and prove to be consistent. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] -
[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20]
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