Blending And Filling Modification Of Polybutylene-1

Polybutylene-1(PB-1) has a reputation of the "gold" plastic. Because of its outstanding mechanical properties, PB-1has been applied in many areas, such as sheet, film, sealant, pipes and so on. For the purpose of more extensive use of PB-1, the mechanical properties and flame retardant performance of PB-1were modified in this study. Ultrafine inorganic particles, which have excellent performance and low price, pioneered the new path of polymer modification. As a new kind of flame retardant, the intumescent flame retardant is halogen-free and do not need to be added toxic substances such as antimony oxides,. Meanwhile, it has good compatibility with polymers. Therefore it has received more and more attention and recognition.In this paper, we first study the influences of different isotacticity on the mechanical properties of PB-1.Experiments show that when the isotactic degree is more than93%, the tensile and bending properties of PB-1decreased. Therefore, we choose polybutylene-1with a93%isotactic degree to be modified. In this experiment, two different particle sizes of ultrafine barium sulfate (250nm and700nm) were chosen, and we studied the modification of its mechanical properties. Results have shown that when the addition amount of larger particle size of ultrafine barium sulfate was7%, the impact on the polybutylene-1performance was improved significantly. And the impact strength increased from49.25KJ/m2to58.44KJ/m2. By using scanning electric microscope (SEM) to observe the shapes and morphologies of the fracture surface, we found that smaller particle size of barium sulfate were prone to reunion in the polymer; and the bigger particle size of barium sulfate have good compatibility with polybutylene-1. Crazing phenomenon was found in the fracture surface, so it can increase the impact strength of polybutylene-1.In this paper, the retardant properties of PB-1were modified by intumescent flame retardant. The results showed that when the content of intumescent flame retardant was10wt%, the oxygen index of PB-1raised from18.8to27.5, which made it join the non-flammable materials, but the UL94was’t V-0. When the content of intumescent flame retardant was25wt%, the UL94was V-0, and the oxygen index of PB-1was38.1, belonging to the flame retardant grade. But at the same time, the mechanical performance of polybutylene-1declined seriously. The tensile strength and elongation at break decreased by45.7%and56.0%respectively.In order to improve the flame retardant efficiency of intumescent flame retardant and the mechanical properties of flame retardant system, this paper studied the synergistic effect of four kinds of silicone oil and intumescent flame retardant. Experimental results has shown that when adding0.6wt%or high temperature silicone oil B, it made polybutylene-1whose content of intumescent flame retardant was20wt%to be v-0, and made its tensile strength increased significantly. The tensile strength increased by19.2%, the elongation at break increased by56.3%. This phenomenon may be caused by the two kinds of silicone oil containg more Ph-Si group. The bond energy is bigger and is not easy to be broken. The combustion can also be suppressed to be a certain extent.This paper also studied the synergistic effect of inorganic rigid particles and intumescent flame retardant.Firstly, flame retardant polybutylene-1, whose content of intumescent flame retardant was10wt%and15wt%, was modified by Titanium dioxide, and it was found that the tensile properties of the system was decreased obviously when added the titanium pigment, and there was no promotion on flame retardant performance. In the experiments, Flame retardant polybutylene-1whose content of intumescent flame retardant was20wt%, was modified by two different particle sizes of ultrafine barium sulfate. The results showed that when the content of ultrafine barium sulfate was2wt%, the tensile performance of system improved significantly. The tensile strength increased by18.6%, and the elongation at break increased by57.8%. Vertical burning time decreased obviously, which made the UL94level improved from v-1to v-0.