Preparation and Performance of a P–N Containing Intumescent Flame Retardant Based on Hydrolyzed Starch

<p>Halogen-free flame retardant is receiving an increased attention recently due to its hypotoxicity and high efficiency. Intumescent flame retardant is a hot spot in research of the halogen-free flame retardant. In this work, a P–N containing intumescent flame retardant named hydrolyzed starch phosphamide from melamine was synthesized via hydrolysis of starch, phosphorylation of the starch with phosphorus oxychloride, and the reaction between the phosphorylated starch and melamine. PU/hydrolyzed starch phosphamide from melamine composites was prepared using different additive amounts of hydrolyzed starch phosphamide from melamine. Fourier transform infrared, scanning electron microscopy, and thermogravimetric analysis were used to characterize the structures and thermal stabilities of related compounds. Flame retardation performance of hydrolyzed starch phosphamide from melamine was investigated by UL94, limit oxygen index test, and cone calorimetry. Result shows that the PU/hydrolyzed starch phosphamide from melamine composites with 30.0 php of hydrolyzed starch phosphamide from melamine got a limit oxygen index of 29.0 and UL94-V0 ranking. Heat release rate, rate of smoke release, and total smoke release were decreased distinctly.</p

The p-value of the pair-wised bootstrap Kolmogorov-Smirnov test of the observed J′ and the five fitting ones predicted by the six responding models in meadows with different successional age.

<p>The p-value of the pair-wised bootstrap Kolmogorov-Smirnov test of the observed J′ and the five fitting ones predicted by the six responding models in meadows with different successional age.</p

The Spearman correlation coefficients (r) and p-value (p) of the Spearman correlation analysis of the relationship between SLA and species relative abundance along the succession gradient.

<p>The Spearman correlation coefficients (r) and p-value (p) of the Spearman correlation analysis of the relationship between SLA and species relative abundance along the succession gradient.</p

The relationship between empirical species richness and evenness with successional age.

<p>p, p-value; r, correlation coefficient.</p

The relationship between empirical species richness and evenness at different sampling spatial scales.

<p>p, p-value; r, correlation coefficient.</p

the species-abundance models which have different evenness in abundance.

<p>the species-abundance models which have different evenness in abundance.</p

The value of the observed and respective fitted J′ of the responding 5 species abundance models of each of the 30 quadrats in the plot of the respective successional age.

<p>The value of the observed and respective fitted J′ of the responding 5 species abundance models of each of the 30 quadrats in the plot of the respective successional age.</p