How to link a storyboard to dynamically created button in silverlight 3.0

Consider , we have a storyboard in the MainPage.xaml in Silverlight 3 :

<UserControl.Resources>

<Storyboard x:Name="muthu">

<DoubleAnimation Storyboard.TargetName="mybutton" Storyboard.TargetProperty="Width" From="0"To="200"/>

</Storyboard>

</UserControl.Resources>

We can link that storyboard to a dynamically created button control like this :

string xaml = @"<Button xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation"" xmlns:x=""http://schemas.microsoft.com/winfx/2006/xaml"" x:Name=""mybutton""/>";

Button btn = (Button)XamlReader.Load(xaml);

this.LayoutRoot.Children.Add(mybutton);

Storyboard.SetTarget(this.sb.Children[0], mybutton);

this.sb.Begin();