You can use elseif to check another page template and you can go on like this.
if ( is_page_template('page-templates/page-1.php') ) {
wp_enqueue_style( 'sentiencesentient-layout-style' , get_template_directory_uri() . '/layouts/style1.css');
} elseif ( is_page_template('page-templates/page-2.php') ) {
wp_enqueue_style( 'sentiencesentient-layout-style' , get_template_directory_uri() . '/layouts/style2.css');
} elseif ( is_page_template('page-templates/page-3.php') ) {
wp_enqueue_style( 'sentiencesentient-layout-style' , get_template_directory_uri() . '/layouts/style3.css');
} elseif ( is_page_template('page-templates/page-4.php') ) {
wp_enqueue_style( 'sentiencesentient-layout-style' , get_template_directory_uri() . '/layouts/style4.css');
} else {
wp_enqueue_style( 'sentiencesentient-layout-style' , get_template_directory_uri() . '/layouts/style5.css');
}