NBR/PVC泡棉是什么材料?(What is NBR/PVC foam material?)
NBR是橡胶,PVC是聚氯乙烯..NBR+PVC就属于橡塑共混改性..其实NBR在里面的作用主要起增韧,回弹和恢复性..根据NBR的比例不同,软硬度也会有区分,一般我们都属称为橡塑弹性体.主要用在密封条或密封件上面使用。
橡胶补强性能影响主要真对拉伸强度和撕裂强度上,其一般规律是:当粒径相同时,高结构炭黑对非结晶橡胶的补强作用大,一般有较高的拉伸强度和撕裂强度。橡胶结构性还是影响导电性能的最重要因素,链枝状结构易于在橡胶中形成交织联结的导电通路,会使导电性能提高。
线型结构:未硫化橡胶的普遍结构。由于分子量很大,无外力作用下,大分子链呈无规卷曲线团状。当外力作用,撤除外力,线团的纠缠度发生变化,分子链发生反弹,产生强烈的复原倾向,这便是橡胶高弹性的由来。
支链结构:橡胶大分子链的支链的聚集,形成凝胶。凝胶对橡胶的性能和加工都不利。在炼胶时,各种配合剂往往进不了凝胶区,形成局部空白,形成不了补强和交联,成为产品的薄弱部位。
交联结构:线型分子通过一些原子或原子团的架桥而彼此连接起来,形成三维网状结构。随着硫化历程的进行,这种结构不断加强。这样,链段的自由活动能力下降,可塑性和伸长率下降,强度,弹性和硬度上升,压缩永久变形和溶胀度下降。
NBR is rubber, PVC is PVC: NBR+PVC belongs to the rubber and plastic blending modification: In fact, the role of NBR in it is mainly to strengthen toughness, rebound and recovery.According to the proportion of NBR, soft and hardness will also be differentiated, generally we are called rubber and plastic elastomers. It is mainly used on sealing strips or seals.
The general law of rubber reinforcing properties mainly affects the tensile strength and tear strength: when the particle size is the same, the reinforcing effect of high-structure carbon black on amorphous rubber is large, and generally has high tensile strength and tear strength.Rubber structure is also the most important factor affecting conductivity, and the chain dendritic structure is easy to form intertwined conductive paths in rubber, which will improve conductivity.
Linear structure: a common structure of unvulcanized rubber.Due to the large molecular weight, under the action of no external force, the macromolecular chain is in the shape of a random curve. When the external force acts, the external force is withdrawn, the entanglement degree of the wire mass changes, and the molecular chain rebounds, resulting in a strong tendency to recover, which is the origin of the high elasticity of rubber.
Branched chain structure: aggregation of branched chains of rubber macromolecular chains to form a gel. The gel is detrimental to both the properties and processing of the rubber.In the process of rubber refining, various compounding agents often cannot enter the gel area, form a local blank, form no reinforcement and cross-linking, and become the weak part of the product.
Cross-linked structure: linear molecules are connected to each other by the bridging of some atoms or atomic groups to form a three-dimensional network structure.This structure is continuously strengthened as the vulcanization process progresses. In this way, the free mobility of the chain segment decreases, plasticity and elongation decrease, strength, elasticity and hardness increase, compression set and swelling decrease.