创新背景

工业和科技发展离不开材料，一直以来，寻找最佳材料发展技术是科研和工业从事者的前进方向。化学键把单体有机分子构成长链形成聚合物，材料类别在原始种类之外有不少人工聚合材料。一维聚合物最典型的塑料，长链首尾相连，因为分子之间联系比较松散，强度有限。二维聚合物（2DP)是一种二维片状单分子大分子，由沿所有边缘具有端基的横向连接的重复单元组成。它通过共价连接单体、配位聚合物和超分子聚合物等方法进行组合，具有良好的材料性能。但之前的研究中总存在无法克服的缺点，如果能够避开二维聚合物的缺陷完成研究实验，会为材料科学、工业和科技发展带来革新发展。

创新过程

麻省理工学院的研究团队针对二维聚合物的缺陷，研究出新型材料，相关研究成果《超强二维聚合物材料的不可逆合成》于2022年2月2日发表在《自然》上。团队所制造的新材料名为2DPA-1二维聚合物，强度超过一般钢材，密度却比普通塑料还低。

以往的二维聚合物因为反应存在可逆性，材料的性质并不稳定，2DPA-1研制过程中避开了从前的修复手段，采用均苯甲酰氯和三聚氰胺的两种化合物的单体分子，它们在一个环上会有有三个120度角排列的分叉，一定条件下分叉利用特殊的分子结构和组合规律连接组合在一起，构成圆盘状大分子，然后进行叠加组件，形成聚合反应不可逆的两层分子，氢键把分子连接在一起，保证了2DPA-1的稳定性。

制备2DPA-1非常简单，可以在溶液中令其自己发生，分子二维地互相结合，在片状的分子平面自发组装。因为它的自发性，聚合物很容易制成涂层、薄膜或片状材料。且二维单体分子直接之间结构的紧密使材料可以完全隔绝水和空气。研究人员表示，因为新材料可以在溶液中自组装，因而可以通过简单地增加起始材料的数量，大量制造非常坚固但极薄的材料。

2DPA-1聚合物的屈服强度，即材料受力极限比普通钢材要强，达到488MPa，密度却只有钢材7.85g/cm3的六分之一，比普通塑料1.38-1.41g/cm3还略低。如果进一步投入研究克服所有缺陷并大量生产，这种高强度轻质材料可以广泛用于薄膜或图层制造业，投入保护材料行业，促进材料科学和各项科技研发进步。

创新关键点

利用单体分子特性组成不可逆聚合物，提高二维聚合物的稳定性。

Irreversible polymers improve 2D polymer properties and contribute to the development of materials science

A research team from MIT has developed new materials for the defects Irreversible polymers improve 2D polymer properties and contribute to the development of materials science two-dimensional polymers. The related research achievement "Irreversible synthesis of an ultrastrong two-dimensional polymeric material" was published in February 2022. Published in "Nature" on the 2nd. The new material the team created, called 2DPA-1, a two-dimensional polymer, is stronger than ordinary steel but lower in density than ordinary plastic.
Due to the reversibility of the reaction of the previous two-dimensional polymers, the properties of the materials are not stable. During the development of 2DPA-1, the previous repair methods were avoided, and the monomer molecules of two compounds, homobenzoyl chloride and melamine, were used. There will be three bifurcations arranged at an angle of 120 degrees on a ring. Under certain conditions, the bifurcations are connected and combined by special molecular structure and combination rules to form a disc-shaped macromolecule, and then superimposed components to form an irreversible polymerization reaction. The two layers of molecules, hydrogen bonds link the molecules together, ensuring the stability of 2DPA-1.
The preparation of 2DPA-1 is very simple. It can be made to occur by itself in solution, and the molecules are two-dimensionally combined with each other and spontaneously assembled in the sheet-like molecular plane. Because of its spontaneity, the polymer is easily made into coatings, films or sheets. And the closeness of the structure between the two-dimensional monomer molecules directly enables the material to completely isolate water and air. The researchers say that because the new material can self-assemble in solution, it is possible to mass-produce very strong but extremely thin materials by simply increasing the amount of starting material.
The yield strength of 2DPA-1 polymer, that is, the stress limit of the material is stronger than that of ordinary steel, reaching 488MPa, but the density is only one-sixth of that of steel 7.85g/cm3, which is slightly lower than that of ordinary plastic 1.38-1.41g/cm3. If further research is devoted to overcome all defects and mass-produced, this high-strength and lightweight material can be widely used in film or layer manufacturing, invested in the protective material industry, and promotes material science and various scientific and technological research and development progress.